JP2004182300A - Packaging film and vapor-deposition film using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a packaging film and a vapor-deposition film of considerably excellent in gas barrier property against oxygen and steam. <P>SOLUTION: In the packaging film, a polyester layer B containing 0.005-0.5 wt.% of aluminum silicate particles is laminated to the thickness of 0.01-5 μm on at least one side of a polyester base film layer A. In the vapor-deposited film, an inorganic thin film is vapor-deposited on a polyester layer B side of the packaging film. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【００３３】
ここで、σは相対標準偏差を、Ｄは数平均粒子径（μｍ）を、Ｄｉは粒子径（μｍ）をｎは粒子個数（個）をそれぞれ表す。相対標準偏差が０．５より大きいと粗大突起が生成し易くなり、均一な表面が得にくく、蒸着の欠陥の原因となり、ガスバリア性が低下するので好ましくない。
【００３４】
また、本発明におけるケイ酸アルミニウム粒子は、粒子の表面がケイ酸アルミニウムで構成されていることが好ましい。このようなケイ酸アルミニウムの製造方法としては、例えば、ｐＨ１０以上のアルカリ水溶液中にアルカリ金属、アンモニウムまたは有機塩基のケイ酸塩と、アルカリに可溶なアルミニウム化合物とを同時に添加し、反応させることにより目的の粒子を生成せしめることができる。このとき、より比表面積の大きな粒子を生成せしめるには、反応液を、ケイ素原子／アルミニウム原子のモル比が０．２５〜１０になるように調整すると、より好ましい。
【００３５】
また、シード粒子をｐＨ９以上のアルカリ水溶液中に分散せしめた上で反応を行うと、シード粒子を核として粒子が成長するため、粒子径の制御が容易になる。 このときのシード粒子としては、相対標準偏差σが０．５以下であり、かつ粒子の長径／短径比が１．０〜１．２であることが好ましく、また、粒子の成長反応の制御が容易なことからシリカ粒子が好適に用いられる。
【００３６】
このように、本発明におけるケイ酸アルミニウム粒子は、ケイ酸アルミニウムで粒子表面を被覆された、ケイ酸アルミニウム被覆粒子を用いることもできる。また、このときのケイ酸アルミニウム層の厚みとしては０．０１〜０．３μｍ、さらには０．０５〜０．２μｍ、特に０．０８〜０．２μｍであることが好ましい。
【００３７】
このようなケイ酸アルミニウム粒子の組成としては、造粒過程における粒子径制御の安定性から、ケイ素原子／アルミニウム原子のモル比が０．２５〜１０であることが好ましく、より好ましくは０．５〜５．０である。
【００３８】
比表面積としては、下記式を満足できる範囲であることが好ましく、多孔質であることが好ましい。
【００３９】
Ｓ≧３．５／Ｄｗ
但し、Ｄｗ：体積平均粒子径（μｍ）Ｓ ：比表面積（ｍ^２／ｇ）である。→上限値は特に限定されないが、好ましくは１０００以下である。
このようなケイ酸アルミニウム粒子は、本発明の効果を妨げない範囲において、ドデシルベンゼンスルホン酸ナトリウム、ラウリル硫酸ナトリウム、ジアルキルスルホコハク酸ナトリウム、ナフタレンスルホン酸のホルマリン縮合物塩などのアニオン系界面活性剤、ポリオキシノニルフェノールエーテル、ポリエチレングリコールモノステアレート、ソルビタンモノステアレートなどの非イオン性界面活性剤、ポリビニルアルコール、ポリビニルピロリドン、ポリエチレングリコールなどの水溶性の合成高分子、ゼラチン、デンプンなどの水溶性の天然高分子、カルボキシメチルセルロースなどの水溶性の半合成高分子、シラン系やチタン系のカップリング剤、リン酸、亜リン酸、ホスホン酸およびこれらの誘導体などのリン化合物などで表面処理されたものも用いることができる。
【００４０】
さらに、本発明の効果を妨げない範囲において、ケイ酸アルミニウム粒子以外の粒子（以下、粒子Ａとする）を併用することができる。このときの粒子Ａの体積平均粒子径は０．００５〜１．０μｍであることが好ましく、０．０１〜０．５μｍであることがより好ましく、さらに、ケイ酸アルミニウム粒子よりも０．１μｍ以上小さいことが好ましい。含有量としてはポリエステルに対し０．００５〜３．０重量％であることが好ましく、０．０１〜２．０重量％であることがより好ましい。粒子Ａの比表面積としては、１０ｍ^２／ｇ以上であることが好ましく、より好ましくは３０ｍ^２／ｇ以上、特に１００ｍ^２／ｇ以上であることが好ましい。本発明における粒子Ａの種類はモース硬度６以上であれば特に限定されず、例えば、酸化ケイ素、酸化チタン、酸化ジルコニウム、酸化アルミニウム、スピネル、酸化鉄などが挙げられる。これらの粒子の中でも酸化ジルコニウム、酸化アルミニウムが特に好ましい。
【００４１】
さらに、上記粒子以外にさらに粒子（以下、粒子Ｂとする）を加えることも好ましい。粒子Ｂの体積平均粒子径は０．０５〜２．０μｍであることが好ましく、さらにケイ酸アルミニウムとの体積平均粒子径の差が０．２μｍ以下であることが好ましい。含有量としては０．００５〜０．３重量％であることが好ましい。粒子Ｂの種類としては、モース硬度４未満の粒子であれば特に限定されないが、例えば、カオリナイト、タルク、硫酸カルシウム、硫酸バリウム、炭酸カルシウム、硫化亜鉛などの無機粒子が挙げられ、これらの中でも炭酸カルシウムが特に好ましい。また、このような無機粒子以外にも、架橋された有機高分子粒子も用いることができる。このような有機高分子粒子としては、少なくとも一部がポリエステルに対し不溶の粒子であればいかなる粒子でも構わない。また、このような粒子の素材としては、ポリイミド、ポリアミドイミド、ポリメチルメタクリレート、ホルムアルデヒド樹脂、フェノール樹脂、ポリスチレン、ポリシルセスキオキ酸、いわゆるシリコーン樹脂など種々のものを使用することができるが、耐熱性が高くかつ粒度分布の均一な粒子が得られ易いビニル系架橋高分子粒子が特に好ましい。
【００４２】
ここで、ビニル系架橋高分子粒子は分子中に唯一個の脂肪族の不飽和結合を有するモノビニル化合物ａと、架橋成分として、分子中に２個以上の脂肪族不飽和結合を有する化合物ｂとの共重合体であることが好ましい。
【００４３】
上記共重合体におけるモノビニル化合物ａの例としては、スチレン、α−メチルスチレン、フルオロスチレン、ビニルピリン、エチルビニルベンゼンなどのモノビニル化合物、アクリロニトリル、メタクリロニトリルなどのシアン化ビニル化合物、メチルアクリレート、エチルアクリレート、プロピルアクリレート、ヘキサデシルアクリレート、オクチルアクリレート、ドデシルアクリレート、ヘキサデシルアクリレート、グリシジルアクリレート、Ｎ，Ｎ’−ジメチルアミノエチルアクリレートなどのアクリル酸エステルモノマー、メチルメタクリレート、エチルメタクリレート、プロピルメタクリレート、イソプロピルメタクリレート、ブチルメタクリレート、ｓｅｃ−ブチルメタクリレート、アクリルメタクリレート、フェニルメタクリレート、ベンジルメタクリレート、２−エチルヘキシルメタクリレート、２−ヒドロキシエチルメタクリレート、グリシルメタクリレート、Ｎ，Ｎ’−ジメチルアミノエチルメタクリレートなどのようなメタクリル酸エステルモノマー、アクリル酸、メタクリル酸、マレイン酸、イタコン酸などのモノまたはジカルボン酸およびジカルボン酸の酸無水物、アクリルアミド、メタクリルアミドなどのアミド系モノマーを使用することができる。上記化合物ａとしては、スチレン、エチルビニルベンゼン、メチルメタクリレートなどが好ましく使用される。
【００４４】
化合物ｂの例としては、ジビニルベンゼン化合物、あるいはトリメチロールプロパントリアクリレート、トリメチロールプロパントリメタクリレート、あるいはエチレングリコールジアクリレート、エチレングリコールジメタクリレート、ポリエチレングリコールジアクリレート、ポリエチレングリコールジメタクリレート、１，３−ブチレングリコールジアクリレート、１，３−ブチレングリコールジメタクリレートなどの多価アクリレートおよびメタクリレートが挙げられる。
【００４５】
化合物ｂのうち特にジビニルベンゼン、エチレングリコールジメタクリレート、またはトリメチロールプロパントリメタクリレートを用いることが好ましい。
【００４６】
ビニル系架橋高分子粒子の組成として、好ましいものを例示すると、ジビニルベンゼン重合体、エチルビニルベンゼン−ジビニルベンゼン共重合体、スチレン−ジビニルベンゼン共重合体、エチレングリコールジメタクリレート重合体、スチレン−エチレングリコールジメタクリレート共重合体、メチルメタクリレート−ジビニルベンゼン共重合体などが挙げられる。ただし、これらの例示に限定されるわけではなく、例えばスチレン−エチルビニルベンゼン−ジビニルベンゼン共重合体、スチレン−エチレングリコールジメタクリレート−メチルメタクリレート共重合体などの３成分以上の共重合系であってもよい。
【００４７】
このようなビニル系高分子粒子は、例えば、化合物ａ，ｂを混合し、以下のような乳化重合により製造する方法がある。
（ａ）ソープフリー重合法、すなわち乳化剤を使用しないか、あるいは極めて小量の乳化剤を使用して重合する方法。
（ｂ）乳化重合に先だって重合系内へ重合体粒子を添加しておいて、乳化重合させるシード法。
（ｃ）単量体成分の一部を乳化重合させ、その重合系内で、残りの単量体を重合させるコア−シェル重合法。
（ｄ）特開昭５４−９７５８２号公報に示されているユーゲルスタットなどによる重合法。
（ｅ）（ｄ）の方法において膨潤助剤を用いない重合法。
【００４８】
ここで、有機高分子粒子は熱天秤による熱分解温度（１０％減量温度、窒素気流中、昇温速度１０℃／分）が３５０℃以上の耐熱性を有する粒子が、ポリエステル組成物製造時、溶融成形時あるいは成形品の再利用回収時に粒子が凝集しにくく、フイルムの表面均一性、耐摩耗性などが低下しない点で好ましく、より好ましくは３６０℃以上、特に３７０℃以上であることが好ましい。このような有機高分子粒子は、粒子を構成する全有機成分に対して、架橋度＝原料モノマの架橋成分の重量／原料モノマーの全重量×１００（％）で定義される架橋度が１０％以上であると、ポリエステルフイルムにしたときに粒子の分散性が良好となり好ましく、より好ましくは３０％以上、特に５５％以上が好ましい。
【００４９】
本発明におけるケイ酸アルミニウム粒子のポリエステルへの配合にあたっては、重合反応系に直接添加する方法以外にも、例えば粒子を溶融状態のポリエステルへ練り込む方法などでも可能である。前者の重合反応系に添加する際の添加時期は任意であるが、エステル交換反応前あるいはエステル化反応後から重縮合反応の減圧開始前までの間が好ましい。後者の練り込みの場合は、粒子を乾燥してポリエステルに練り込む方法でもスラリー状態で減圧しながら直接練り込む方法でも構わない。
【００５０】
このようにして得られたポリエステルＢ層の組成物は、目的に応じて、希釈用ポリエステルなどの他のポリエステルとブレンドして用いても構わない。
【００５１】
また、本発明の包装用フィルムにおいて、基材フィルム層の少なくとも片面に形成されるポリエステルＢ層は、蒸着膜密着性、ガスバリア性の点から、９５〜６０重量％のエチレンテレフタレート成分と５〜４０重量％のブチレンテレフタレート成分からなるポリエステルであることが好ましい。より好ましくは５〜３０重量％、透明性、寸法安定性の点から、特に好ましくは５〜２５重量％である。
【００５２】
また、本発明のポリエステルＢ層の積層厚みは０．０１〜５μｍであることが必要である。０．０１μｍ未満であると優れた蒸着膜との密着性、ガスバリア性が得られ難い。逆に積層厚みが５μｍを越えると、生産性の点で好ましくない。より好ましくは０．０５〜５μｍ、さらに好ましくは０．１〜５μｍである。
【００５３】
また、ポリエステルＢ層のエチレンテレフタレート成分とブチレンテレフタレート成分の混合の方法は、重合段階でグリコール成分としてエチレングリコールと１，４−ブタンジオールの共存下でテレフタル酸とエステル化もしくはエステル交換反応により重縮合して共重合ポリエステルとする方法、ポリエチレンテレフタレートとポリブチレンテレフタレートを別々に重合、ペレット化し、製膜時に所定の混合比となるようにブレンド、乾燥し、溶融押出を行うことで混合する方法などが挙げられるが、後者の別々に重合したポリエステルを混合する方法が好ましく用いられる。また、溶融押出の際にエステル交換反応を抑制するために、ポリエステル樹脂中の重合触媒を失活させる目的で、固体もしくは液体のリン化合物を添加しても良い。
【００５４】
また、本発明のポリエステルフィルムを構成するポリエステル樹脂はエチレンテレフタレート成分およびブチレンテレフタレート成分以外の成分を共重合しても良く、成形性を付与するためにイソフタル酸やダイマー酸、１，３−ドデカジオン酸などが好ましい共重合成分として使用できる。勿論、ポリエステル樹脂にポリオキシアルキレングリコール成分を予め共重合しておいて製膜する、もしくは別途ポリエーテルエステルとして準備し、ポリエステル樹脂とブレンドして使用しても良い。
【００５５】
本発明のポリエステルフィルムは耐熱性、蒸着性、寸法安定性の観点から、示差走査熱量計で測定される融点が一つだけ存在することが好ましい。融点としては２４５〜２６０℃の間であることが特に好ましい。通常ポリエチレンテレフタレートとポリブチレンテレフタレートをブレンドすると融点が各々のポリエステルに起因して２つの融点が測定されるが、溶融押出の際にポリエステルをナノメートルオーダーでアロイ化することで融点を一つにすることができ、かつエステル交換反応を抑制することで優れた蒸着密着性を達成することができ、その結果優れたガスバリア性を達成することができる。
【００５６】
本発明のポリエステルを重合するに際しては、適宜反応触媒、着色防止剤を選択して使用することができ、反応触媒としてはたとえばアルカリ金属化合物、アルカリ土類金属化合物、亜鉛化合物、鉛化合物、マンガン化合物、コバルト化合物、アルミニウム化合物、アンチモン化合物、チタン化合物、ゲルマニウム化合物などを、着色防止剤としてはリン化合物などを使用することができるが、特にこれらに限定されるものではない。内容物取出性の観点からはアルカリ金属化合物および／もしくはアルカリ土類金属化合物を反応触媒に用いることが好ましい。
【００５７】
重合触媒の添加に関しては、ポリエステルの製造が完結する以前の任意の段階において、重合触媒としてアンチモン化合物、ゲルマニウム化合物および／またはチタン化合物を添加することが好ましい。このような方法としては、例えば、ゲルマニウム化合物を例にすると、ゲルマニウム化合物粉体をそのまま添加する方法や、あるいは特公昭５４−２２２３４号公報に記載されているように、ポリエステルの出発原料であるグリコール成分中にゲルマニウム化合物を溶解させて添加する方法などを使用することができる。
【００５８】
ここで、ゲルマニウム化合物としては、例えば、二酸化ゲルマニウム、水酸化ゲルマニウム水和物あるいはゲルマニウムテトラメトキシド、ゲルマニウムエチレングリコキシドなどのゲルマニウムアルコキシド化合物、ゲルマニウムフェノキシド化合物、リン酸ゲルマニウム、亜リン酸ゲルマニウムなどのリン酸含有ゲルマニウム化合物、酢酸ゲルマニウムなどを使用することができる。なかでも二酸化ゲルマニウムが好ましく用いられ、非晶質の二酸化ゲルマニウムが特に好ましく用いられる。
【００５９】
また、アンチモン化合物としては特に限定されないが、例えば、三酸化アンチモンなどの酸化物、酢酸アンチモンなどが使用される。
【００６０】
また、チタン化合物としては特に限定されないが、モノブチルチタネートやジブチルチタネートなどやチタンテトラエトキシド、チタンテトラブトキシドなどのチタンテトラアルコキシドが好ましく用いられる。
【００６１】
例えば、ポリエチレンテレフタレートを製造するに際して、触媒として二酸化ゲルマニウムを添加する場合には、テレフタル酸成分とエチレングリコール成分をエステル交換またはエステル化反応させ、次に二酸化ゲルマニウム、リン化合物を添加し、引き続き高温、減圧下で一定のジエチレングリコール含有量になるまで重縮合させ、ゲルマニウム元素含有重合体を得る方法が好ましく用いられる。
【００６２】
本発明の積層フィルムは、例えば次のような方法によって成形することができる。
ポリエステル組成物のペレットを十分乾燥した後、ただちに押出機に供給する。このペレットを２６０〜３５０℃で溶融し、ダイよりシート状に押出し、キャスティングロール上で冷却、固化させて未延伸フイルムを得る。次に、この未延伸フイルムを二軸延伸するのが好ましい。延伸方法としては、逐次二軸延伸法、同時二軸延伸法、あるいはこのように二軸に延伸したフイルムを再度延伸する方法などを用いてもよい。ポリエステルの組成によるが、例えば、磁気記録媒体用フイルムとして十分な弾性率を得るには最終的な延伸面積倍率（縦倍率×横倍率）を６以上とすることが好ましい。
【００６３】
また、フイルムの熱収縮率を小さく保つため１５０〜２６０℃の温度範囲で０．１〜６０秒程度の熱処理を行うことが好ましい。
【００６４】
本発明における包装用フィルムのポリエステルＢ層にはケイ酸アルミニウム粒子以外の粒子を添加することもできる。かかる粒子は平均粒子径０．０１〜２μｍのの内部粒子および外部粒子が好ましい。
【００６５】
内部粒子としては、例えば、特開昭４８−６１５５６号公報に記載のリチウム元素を含有する内部粒子、特開昭５３−４１３５５号公報に記載のリチウム元素、カルシウム元素およびリン元素を含有する内部粒子、特開昭５４−９０３９７号公報に記載のリチウム化合物、リチウム化合物とカルシウム化合物の内部粒子等の技術を採用することができる。さらに、特開昭５９−２０４６１７号公報に記載のアルカリ金属元素またはアルカリ土類金属元素の一種以上を構成成分の一部とする内部粒子などの他の粒子を併用することもできる。
【００６６】
また、内部粒子の無機粒子としては、たとえば湿式および乾式シリカ、コロイダルシリカ、ケイ酸アルミ、酸化チタン、炭酸カルシウム、リン酸カルシウム、硫酸バリウム、酸化アルミ、マイカ、カオリン、クレーなど、外部粒子の有機粒子としてはスチレン、シリコーン、アクリル酸類、メタクリル酸類、ポリエステル類、ジビニル化合物などを構成成分とする粒子を使用することができる。なかでも、湿式および乾式シリカ、アルミナなどの無機粒子およびスチレン、シリコーン、アクリル酸、メタクリル酸、ポリエステル、ジビニルベンゼンなどを構成成分とする粒子を使用することが好ましい。さらに、これらの内部粒子、外部粒子は二種以上を併用してもよい。これらの中でも特に外部粒子の無機粒子を好ましく用いることができ、中でも乾式または湿式シリカが好ましく用いられる。また、粒子の添加量はガスバリア性の点で０．０１〜０．１重量％であるとより好ましい。さらに好ましくは、０．０１〜０．０５重量％である。粒子の添加量が０．５重量％より多い場合は、蒸着を行った場合に蒸着層に蒸着の欠陥が発生する場合があり、ガスバリア性が低下する場合がある。
【００６７】
本発明おける包装用フィルムは、積層フィルムにおける無機薄膜形成側の表面（蒸着膜形成面という）の中心線平均表面粗さ（Ｒａ）が０．００５〜０．０３０μｍの範囲であることが好ましい。より好ましくは０．００８〜０．０２５μｍ、さらに好ましくは０．０１〜０．０２μｍである。蒸着膜形成面のＲａを上記範囲内とすることにより、良好なフィルムのハンドリング性（滑り性）、さらには優れた加工性を得ることができる。即ち、Ｒａが０．００５μｍ未満であると、フィルムのハンドリング性が悪化し易いので好ましくない。Ｒａが０．０３μｍを越えると、耐傷性が悪化すると共に蒸着時に蒸着の欠陥が生じやすくなるので好ましくない。Ｒａを上記の範囲とする方法は特に限定されないが、基材フィルム層（Ａ層）中に粒子を含有させる方法が好ましく、梨地模様の金属ドラムに接触させてフィルム表面にドラム表面の凹凸を転写させる方法であっても構わない。
【００６８】
また、蒸着膜形成面とは反対側のフィルム表面（非蒸着面という）のＲａは０．００８〜０．０５μｍが好ましく、さらには０．０１〜０．０３μｍが好ましい。非蒸着面のＲａが０．０５μｍを越えると滑り性が高すぎてかえってハンドリング性が低下するなどの蒸着特性、加工性が悪化するので好ましくない。この非蒸着面のＲａと蒸着膜形成面のＲａとの差（ΔＲａ）は０．００３〜０．０４５μｍが好ましく、さらに好ましくは０．００５〜０．０４５μｍである。
【００６９】
本発明の包装用フィルムにおいて、積層フィルムの面配向係数（ｆｎ）は、０．１５５〜０．１８０の範囲であることが好ましく、より好ましくは０．１６２５〜０．１７５の範囲である。ｆｎが０．１５５未満であると、フィルムの配向性が低下するため強度低下や外力に対して伸びやすくなり、加工適性が低下しやすいため好ましくない。逆に０．１８０を越えると、フィルムの幅方向の物性ムラや白化等が生じやすいので好ましくない。
【００７０】
また、本発明の包装用フィルムにおいて、積層フィルムの、１５０℃、３０分加熱したときの熱収縮率は、フィルムの長手方向で０．５〜２％、幅方向で−１．２〜０．５％の範囲であることが好ましく、さらに好ましくはフィルムの長手方向で１〜２％、幅方向で−１〜０％である。熱収縮率がフィルム長手方向で２％、幅方向で０．５％を越える場合や幅方向で−１．２％未満であると蒸着時やラミネート、印刷工程等の外力が負荷される加工時に寸法変化が大きくなりやすいので好ましくない。長手方向の１５０℃、３０分加熱したときの熱収縮率はできるだけ小さい方が好ましいが、０．５％程度を有することから、長手方向の熱収縮率の下限は実質的に０．５％である。ここで熱収縮率のマイナス（−）の値は伸びを示すものである。
【００７１】
さらに本発明における包装用フィルムの厚みは特に限定しないが、好ましくは１〜３００μｍ、より好ましくは５〜１００μｍである。
【００７２】
本発明の包装用フィルムを作成するためには、前記した積層フィルムの、基材フィルム層（Ａ層）の他の積層側の表面に、蒸着による無機薄膜を形成することが必要である。この際、蒸着を施す表面にコロナ放電処理を施し、表面の濡れ張力を３５ｍＮ／ｍ以上に上げることは、蒸着無機薄膜の密着性を向上させるため好ましく採用できる。この時のコロナ放電処理時の雰囲気ガスとしては、空気、炭酸ガス、または窒素／炭酸ガスの混合系のいずれでもよく、特に炭酸ガスまたは窒素／炭酸ガスの混合ガス（体積比＝９５／５〜５０／５０）中でコロナ処理すると、フィルム表面の濡れ張力が３５ｍＮ／ｍ以上に上がるので好ましい。
【００７３】
このコロナ放電処理をした表面に無機薄膜を蒸着によって形成する。この無機薄膜を構成する材質としては、アルミニウムや、および／またはアルミニウム、珪素、亜鉛、マグネシウムなどの金属酸化物が好ましい。金属酸化物の中では、酸化アルミニウムがガスバリア性能とコストの面からより好ましい。金属酸化物はこれらのものの単独でもよく、複数が混合したものでもよく、金属成分が一部残存したものでもよい。
【００７４】
蒸着によりこれら無機薄膜を形成する方法としては、通常の真空蒸着法を用いることができるが、イオンプレーティングやスパッタリング、プラズマで蒸発物を活性化する方法などを用いることができる。金属酸化物の膜を形成する方法としては、金属酸化物を直接蒸発により堆積する方法でもよいが、酸化雰囲気下での反応性蒸着による方法が生産性の上からより好ましい。また化学気相蒸着法（いわゆるＣＶＤ法）も広い意味での蒸着法として用いることができる。酸化雰囲気とするためには、酸素ガス単独または酸素ガスを不活性ガスで希釈した気体を真空蒸着機中に必要量導入すればよい。不活性ガスとはアルゴンやヘリウムなどの希ガスや窒素ガスおよびこれらの混合ガスを指す。反応性蒸着は、こういった酸化雰囲気下で金属または金属酸化物を蒸発源から蒸発させ、基材フィルム近傍で酸化反応を起こさせ、基材フィルム上に無機薄膜を形成する手法により行われる。これらのための蒸発源としては、抵抗加熱方式のボード形式や、輻射または高周波加熱によるルツボ形式や、電子ビーム加熱による方式などがあるが、特に限定されない。
【００７５】
無機薄膜が金属酸化物からなる場合は、完全酸化物であることが最も好ましい。しかし、一般に完全酸化物を形成しようとすると、過剰に酸化された部分が形成される確率が高く、過剰酸化部分のガスバリア性能が劣り、全体として高いガスバリア性能を得ることは難しい。このため、多少金属成分が残った不完全酸化膜であってもよい。
【００７６】
蒸着フィルムの光線透過率は好ましくは７０％以上、より好ましくは８０％以上、さらに好ましくは８５％以上であることが、包装袋として用いた場合に内容物を品質確認する上で好ましい。その光線透過率の上限は、基材フィルム層（Ａ層）の光線透過率による制限を受け、一般的なポリエステルフィルムの光線透過率の上限値（９２％）が、実質的な光線透過率の上限値となる。
【００７７】
無機薄膜の厚みは、アルミニウム薄膜の場合、２０〜５０ｎｍの厚みが好ましく、光学濃度（光線透過率の逆数の対数）が１．５〜３．０程度のものが蒸着される。また金属酸化物の場合、ガスバリア性能および可撓性などの点で、好ましくは５〜１００ｎｍ、より好ましくは８〜５０ｎｍの厚みが用いられる。膜厚が５ｎｍ未満では、ガスバリア性能が十分でない。膜厚が１００ｎｍを超えると蒸着時に金属酸化物の凝集潜熱により、フィルムの極表面が溶融して白化する熱負けの発生や、蒸着膜の可撓性が悪くなり、さらにフィルムの折り曲げなどにより、蒸着薄膜の割れや、剥離が生じやすくなるので好ましくない。
【００７８】
本発明の包装用フィルムは、無機薄膜の蒸着面の上に、他の樹脂を積層することもできる。積層される他の樹脂としては、ポリオレフィン系樹脂、ナイロン樹脂、ポリエチレンテレフタレート樹脂などが好ましく、二軸延伸フィルムの積層でも無延伸フィルムの積層でも構わない。ヒートシール層として積層する場合は、ポリオレフィン系樹脂の無延伸フィルムが好ましく、これらのフィルムを押出ラミネート法または接着剤などで積層することが好ましい。この場合の蒸着フィルムは、ヒートシール層同士を重ね合わせてシールされて包装袋として使用される。
【００７９】
本発明の包装用フィルムはポリエステルフィルムの特長である、低吸湿性、寸法安定性、平面性、透明性を維持したまま、優れたガスバリア性を有することから食品包装用途などに好ましく使用することができる。
【００８０】
本発明のフィルムを構成する各フィルム層中には、必要に応じて、難燃剤、熱安定剤、酸化防止剤、紫外線吸収剤、帯電防止剤、顔料、染料、脂肪酸エステル、ワックス等の有機滑剤またはポリシロキサン等の消泡剤を配合することもできる。
【００８１】
また、本発明の蒸着用包装フィルムにおいて、無機薄膜を形成する前の積層フィルムは、種類の異なるポリマーを用いて、例えば特開平９−２４５８８号公報に示される、ポリエステルＡ（融点２２０〜２７０℃）層に少なくとも片面にポリエステルＢ（１５０℃〜２４５℃）層を積層して、Ａ層とＢ層の融点差が５〜６０℃を有するような積層構造とすることができる。かかる積層フィルムの形態は、特に限定されないが、例えば、基材フィルム層（Ａ層）／ポリエステル層（Ｂ層）／を、それぞれ、Ａ、Ｂで表した場合、Ａ／Ｂ、Ｂ／Ａ／Ｂなどの積層形態を挙げることができるが、ブロッキング性と蒸着性の両方を満足させるには、Ａ／Ｂ積層形態が好ましい。積層厚み比も任意に設定して構わない。さらに、これら以外の層を積層してもよく、例えば、帯電防止層、マット層、ハードコート層、易滑コート層、易接着層、粘着層などを必要に応じて積層してもよい。
【００８２】
本発明において、無機薄膜を形成する前の積層フィルムの製造方法は特に限定されない。ここでは、基材フィルム（Ａ）、ポリエステル層（Ｂ層）のそれぞれを構成する樹脂として、ポリエステルＡ、ケイ酸アルミニウムを含有するポリエステルＢを用い、二軸延伸フィルムとする場合を例にとって、以下説明する。
【００８３】
ポリエステルＡ、ポリエステルＢをそれぞれ、通常のホッパドライヤー、パドルドライヤー、真空乾燥機等を用いて乾燥した後、別々の押出機にそれぞれ供給して、２００〜３２０℃で溶融し、スリット状の２層口金に導き、２層積層されたシート状にして押出し、急冷してポリエステルＡ／ポリエステルＢの積層未延伸フィルムを得る。Ｔダイ法を用いた場合、急冷時にいわゆる静電印加密着法を用いることにより、厚みの均一なフィルムを得ることができるので好ましい。次いでこの未延伸フィルムを同時または逐次に二軸延伸する。逐次二軸延伸の場合、その延伸順序はフィルムを長手方向および幅方向の順とすればよいが、この逆の順としてもよい。さらに、逐次二軸延伸においては、長手方向または幅方向の延伸をそれぞれ２回以上行うことも可能である。延伸方法については特に制限はなく、ロール延伸、テンター延伸等の方法が適用され、形状面においてはフラット状、チューブ状等どのようなものであってもよい。フィルムの長手方向および幅方向の延伸倍率は目的とする蒸着適性、配向性などに応じて任意に設定することができるが、好ましくは１．５〜６．０倍である。延伸温度はポリエステルのガラス転移温度以上、結晶化温度以下の範囲であれば任意の温度とすることができるが、通常は３０〜１５０℃が好ましい。さらに、二軸延伸の後にフィルムの熱処理を行うことができる。熱処理温度はポリエステルＡの融点以下の任意の温度とすればよいが、好ましくは２００〜２４０℃である。熱処理はフィルムを長手方向および／または幅方向に弛緩させつつ行ってもよい。
【００８４】
このようにして得られた積層フィルムは、次に、蒸着処理されるが、この蒸着処理の前に、蒸着を施す表面を接着促進処理、例えば空気中やその他の雰囲気下でのコロナ放電処理、火炎処理、紫外線処理等を施してもよい。コロナ放電処理の場合、雰囲気ガスとしては、空気、炭酸ガス、または窒素／炭酸ガスの混合系のいずれでもよく、特に炭酸ガスまたは窒素／炭酸ガスの混合ガス（体積比＝９５／５〜５０／５０）中でコロナ処理すると、フィルム表面の濡れ張力が３５ｍＮ／ｍ以上に上がるので好ましい。
【００８５】
次に、接着促進処理されたフィルムを、フィルム走行装置を具備した真空蒸着装置内にセットし、冷却金属ドラムを介して走行させる。この時、アルミニウム金属を加熱蒸発させながら、蒸発した金属蒸気によって蒸着を行う。または、金属蒸気の存在する箇所に酸素ガスを供給し、アルミニウムを酸化させながら走行フィルム面に凝集堆積させ、酸化アルミニウム蒸着層を形成し、巻き取る。この時のアルミニウムの蒸発量と供給酸素ガス量の比率を変更することで、酸化アルミニウム蒸着フィルムの光線透過率を変更することができる。蒸着後、真空蒸着装置内を常圧に戻して巻き取ったフィルムをスリットする。この後、３０℃以上の温度で１日以上放置してエージングするとガスバリア性が安定化するので好ましい。
【００８６】
【実施例】
次に、本発明の効果を実施例により説明するが、本発明がこれらの実施例に限定されるものではない。まず、特性値の測定方法および評価方法を以下に示す。
【００８７】
［特性値の測定方法・評価方法］
本発明の粒子特性およびフィルム特性値は次の測定法による。
（Ａ）粒子特性
（１）粒子径比、平均粒子径、粒度分布の測定および相対標準偏差σの計算
粒子をポリエステルに配合し、０．２μｍ厚みの超薄切片にカッティング後、透過型電子顕微鏡で、少なくとも１００個の粒子について観察し測定した。相対標準偏差σ、平均粒子径の計算式は下記のとおりである。
【００８８】
【数２】

【００８９】
ただし、σは相対標準偏差を、Ｄは数平均粒子径（μｍ）を、Ｄｉは粒子径（μｍ）をｎは粒子個数（個）をそれぞれ表す
（２）粒子の比表面積
不活性ガスの吸着量から固体の比表面積をもとめる方法（ＢＥＴ法）により測定を行った。
【００９０】
（３）ケイ素原子／アルミニウム原子のモル比
蛍光Ｘ線分析法により測定を行った。
【００９１】
（４）粒子の熱分解温度
理学電気ＴＡＳ−１００にて窒素雰囲気下、昇温速度２０℃／分での熱天秤減量曲線を測定し、１０％減量温度を熱分解温度とした。
（Ｂ）フイルム特性
（１）ガラス転移温度（Ｔｇ）
Ｓｅｉｋｏ Ｉｎｓｔｒｕｍｅｎｔ（株）製の熱分析装置ＤＳＣＩＩ型を用い、サンプル５ｍｇを３００℃で５分間保持し、液体窒素で急冷した後、昇温速度２０℃／分で昇温した際の転移点の中心温度を測定し、ガラス転移温度（Ｔｇ）とした。
【００９２】
（２）融点（Ｔｍ）
Ｓｅｉｋｏ Ｉｎｓｔｒｕｍｅｎｔ（株）製の熱分析装置ＤＳＣＩＩ型を用い、サンプル５ｍｇを室温より２０℃／分の昇温速度で昇温していった際の吸熱融解曲線のピーク温度を測定し、融点（Ｔｍ）とした。
【００９３】
（３）固有粘度
ポリエステルをオルソクロロフェノールに溶解し、２５℃において測定した。
【００９４】
（４）面配向係数ｆｎ
アタゴ（株）製アッベ屈折計を用い、光源をナトリウムランプとして、フィルムの屈折率の測定を行った。フィルム面内の長手方向の屈折率ｎγ、それに直行する横方向の屈折率ｎβおよび厚み方向の屈折率ｎαを求め、下記式
ｆｎ＝（ｎγ＋ｎβ）／ｎα
により面配向係数ｆｎを求めた。
【００９５】
（５）平均粒子径
フィルム中に含まれる粒子の粒子径を求める際には、次の方法を用いることができる。
【００９６】
フィルムから樹脂をプラズマ低温灰化処理法で除去し、粒子を露出させる。処理条件は樹脂が灰化するするが、粒子がダメージを受けない条件を選択する。これを走査型顕微鏡で粒子数５，０００〜１０，０００個を観察し、粒子画像を画像処理装置により円相当径から平均粒子径を求めた。
【００９７】
粒子が内部粒子の場合、ポリマー断面を切断し厚さ０．１〜１μｍ程度の超薄切片を作製し、透過型電子顕微鏡を用いて倍率５，０００〜２０，０００程度で写真を撮影（１０枚：２５ｃｍ×２５ｃｍ）し、内部粒子の平均分散径を円相当径より計算した。
【００９８】
（６）中心線平均粗さ（Ｒａ）
小坂研究所製の高精度薄膜段差測定器ＥＴ−１０を用いて表面粗さを測定した。条件は次の通りであり、２０回の測定の平均値を中心線平均粗さ（Ｒａ）とした。
・触針先端半径：０．５μｍ
・触針荷重 ：５ｍｇ
・測定長 ：１ｍｍ
・カットオフ ：０．０８ｍｍ
なお、Ｒａの定義は、例えば、河村末久、中村義一著「表面測定技術とその応用」（共立出版株式会社）第５章表面粗さ測定法Ｐ１３４〜に示されているものである。
【００９９】
（７）熱収縮率
フィルムサンプルの表面に、標線間距離２００ｍｍで表線を描き、フィルム幅１０ｍｍで切断した。このサンプルを長さ方向に吊し、１ｇの荷重を長さ方向に加えて、１５０℃の熱風を用い３０分間加熱した後、標線間の長さを測定し、フィルムの収縮量を原寸法に対する割合（百分率（％））で求めた。なお、フィルムが伸長した場合はマイナス（−）値で表示した。
【０１００】
（８）光学濃度（ＯＤ）
蒸着フィルムをＪＩＳ−Ｋ−７６０５に従い、マクベス社製の透過濃度計ＴＲ９２７を用いて、フィルターをＶｉｓｕａｌとしたときの透過濃度を測定し、光学濃度とした。
【０１０１】
（９）光線透過率
蒸着フィルムを日立製作所社製分光々度計３２４型を用いて、波長５５０ｎｍでの透過率を求めた。
【０１０２】
（１０）ガスバリア性
Ａ．水蒸気透過率（防湿性）
モダンコントロール社製の水蒸気透過率計“ＰＥＲＭＡＴＲＡＮ”Ｗ３／３１を用いて、温度３７．８℃、相対湿度１００％の条件下で測定した値を、ｇ／ｍ２・日の単位で示した。
【０１０３】
Ｂ．酸素透過率
モダンコントロール社製の酸素透過率計“ＯＸＴＲＡＮ”−１００を用いて、温度２３℃、相対湿度８０％の条件下で測定した値を、ｍｌ／ｍ２・日・ＭＰａの単位で示した。
【０１０４】
（１１）フィルムの厚み構成および無機薄膜層の厚み
フィルムの断面を透過型電子顕微鏡（ＴＥＭ）にて下記の条件で写真撮影し、フィルムの厚み構成および無機薄膜層の厚みを測定した。

（１２）蒸着膜密着性
蒸着フィルムの蒸着面上にポリウレタン系接着剤を用いて無延伸プロピレンフィルム（ＣＰＰ）（東レ合成フィルム（株）製Ｔ３９３１、６０μｍ）を貼り合わせ、４０℃で４８時間エージング後１５ｍｍ幅に切断して、“テンシロン”を用いてＣＰＰと蒸着無機薄膜の１８０゜剥離を剥離速度１００ｍｍ／分で行った。ドライ（２５℃、５０％ＲＨ雰囲気下）での剥離強力を測定した。剥離強力が２Ｎ／ｃｍ以上のものを○、１Ｎ／ｃｍ未満のものを×、その中間のものを△として蒸着膜密着性を評価した。
【０１０５】
（１３）ハンドリング性
蒸着および加工時のフィルムの取扱性（滑り性など）について、取扱性が優れるものを○、取扱性が劣るが実用性問題ないものを△、取扱性が劣るものを×として評価した。
【０１０６】
次に、本発明のフィルムの製造方法について、フィルム／表面処理／無機薄膜の順に積層した一例を挙げて説明するが、本発明がこの例に限定されるものではないことはもちろんである。
【０１０７】
【実施例】
実施例および比較例には、以下のケイ酸アルミニウム粒子、粒子マスターおよびポリエステルを使用した。
（ケイ酸アルミニウム粒子Ａ）ケイ酸ナトリウム３．５重量％溶液をＨ型イオン交換樹脂カラムを通して脱塩し、これに、水酸化ナトリウム１．５重量％溶液を加えてＰＨ＝９とした。得られた混合溶液の２０重量％を分取し、１００℃で１０分間加熱後、９０℃まで降温し、残りの混合溶液を少量ずつ、攪拌しながら加え、粒子径が０．３０μｍになるまで粒子を成長させることによりシリカのシード粒子を得た。
【０１０８】
次いで、このシード粒子の５重量％スラリーを水酸化ナトリウムでｐＨ＝１２．５に調整し、これにアルミン酸ナトリウム０．５重量％溶液と、水ガラス１．５重量％溶液をそれぞれを同時に添加し、その一部を分取し撹拌しながら１００℃で加熱後９０℃に降温保持し、残りの水溶液を添加速度１００ｇ／分で加えて撹拌速度５０ｒｐｍで撹拌し、体積平均粒子径が０．５３μｍになるまで成長させ得られた粒子含有水溶液を、１００倍の純水を用いて稀釈した後、１５０〜２５０℃の温度で噴霧乾燥させることによりケイ酸アルミニウム粒子Ａ（体積平均粒子径：０．５３μｍ、粒子径比：１．０２、比表面積：８．７ｍ^２／ｇ、珪素／アルミニウム比：３．２、相対標準偏差：０．０９、屈折率：１．４８２）を得た。混合比率は、シード粒子５重量％／アルミン酸ナトリウム０．５重量％溶液／水ガラス１．５重量％溶液＝２．５重量％／３０．９重量％／２０．２重量％である。
（ケイ酸アルミニウム粒子Ｂ）シード粒子の粒子径が０．１０μｍになるまで粒子を成長させたことおよび水溶液の混合比率（シード粒子５重量％／アルミン酸ナトリウム０．５重量％溶液／水ガラス１．５重量％溶液＝０．２５重量％／１９．７重量％／１３．０重量％）を変更した以外は、ケイ酸アルミニウムＡと同様の手法でケイ酸アルミニウム粒子Ｂ（体積平均粒子径：０．３１μｍ、粒子径比：１．０４、比表面積：１５．２ｍ^２／ｇ、珪素／アルミニウム比：２．３、相対標準偏差：０．１０、屈折率：１．５２１）を得た。
（ケイ酸アルミニウム粒子Ｃ）シード粒子の粒子径が０．１３μｍになるまで粒子を成長させたことおよび水溶液の混合比率（シード粒子５重量％／アルミン酸ナトリウム０．５重量％溶液／水ガラス１．５重量％溶液＝２．５重量％／３５．４重量％／１１．１重量％）を変更した以外は、ケイ酸アルミニウムＡと同様の手法でケイ酸アルミニウム粒子Ｃ（体積平均粒子径：０．２０μｍ、粒子径比：１．０１、比表面積：２３．１ｍ^２／ｇ、珪素／アルミニウム比：２．１、相対標準偏差：０．１３、屈折率：１．５１２）を得た。
（粒子マスターＡ）上記ケイ酸アルミニウム粒子Ａを１０重量％、エチレングリコール９０重量％を混合して常温下２時間ディゾルバーで撹拌処理し、ケイ酸アルミニウム粒子のエチレングリコールスラリー（Ａ）を得た。
【０１０９】
次に、テレフタル酸ジメチルを１００重量％、エレチングリコール４４重量％に、触媒として酢酸マグネシウムを加えてエステル交換反応を行った後、反応生成物に先に調製したスラリー（Ａ）０．５重量部、触媒の三酸化アンチモン、および耐熱安定剤としてトリメチルホスフェートを加え重縮合反応を行い、ケイ酸アルミニウム粒子を１重量％含有するポリエチレンテレフタレートを得た。
（粒子マスターＢ）上記ケイ酸アルミニウム粒子Ｂを用い、粒子マスターＡと同様にしてケイ酸アルミニウム粒子を１重量％含有するポリエチレンテレフタレート樹脂を得た。
（粒子マスターＣ）上記ケイ酸アルミニウム粒子Ｃを用い、粒子マスターＡと同様にしてケイ酸アルミニウム粒子を１重量％含有するポリエチレンテレフタレート樹脂を得た。
（粒子マスターＤ）凝集シリカ粒子（体積平均粒子径：１．４μｍ、屈折率：１．６１８）を用い、粒子マスターＡと同様にして凝集シリカ粒子を２重量％含有するポリエチレンテレフタレート樹脂を得た。
（粒子マスターＥ）コロイダルシリカ粒子（体積平均粒子径：０．３５μｍ、屈折率：１．６２３）を用い、粒子マスターＡと同様にしてコロイダルシリカ粒子を１重量％含有するポリエチレンテレフタレート樹脂を得た。
（ポリエチレンテレフタレートＡ（ＰＥＴ−Ａ））テレフタル酸ジメチル１００重量％、エチレングリコール６０重量％の混合物に、テレフタル酸ジメチル量に対して酢酸マグネシウム０．０９重量％、三酸化アンチモン０．０３重量％を添加して、常法により加熱昇温してエステル交換反応を行なった。次いで、該エステル交換反応生成物に、テレフタル酸ジメチル量に対して、リン酸８５％水溶液０．０２０重量％を添加した後、重縮合反応層に移行する。次いで、加熱昇温しながら反応系を徐々に減圧して１ｍｍＨｇの減圧下、２９０℃で常法により重縮合反応を行い、ポリエチレンテレフタレート樹脂（融点２５６℃、固有粘度０．６４）を得た。
（ポリエチレンナフタレートＡ（ＰＥＮ−Ａ））テレフタル酸ジメチルの替わりに２，６−ナフタレンジカルボン酸ジメチルを１００重量％としたこと以外は、ＰＥＴ−Ａと同様にしてポリエチレンナフタレート樹脂（融点２７０℃、固有粘度０．６９ｄｌ／ｇ）を得た。
（ポリブチレンテレフタレートＡ（ＰＢＴ−Ａ））東レ製登録商標“トレコン”１２００Ｓのポリブチレンテレフタレート（融点２２８℃、固有粘度１．２６ｄｌ／ｇ）を用いた。
（ポリエーテルエステルＡ（ＰＥＥ−Ａ））東レ・デュポン製登録商標“ハイトレル”３０７８のポリエーテルエステル（融点１７０℃、メルトフローインデックス（ＭＩ）５．０ｇ／分）を用いた。
（ポリエーテルエステルＢ（ＰＥＥ−Ｂ））東レ・デュポン製登録商標“ハイトレル”７２７７のポリエーテルエステル（融点２１９℃、メルトフローインデックス（ＭＩ）１．５ｇ／分）を用いた。
【０１１０】
以上のようにして準備した樹脂の組成を表１に示す。これらの樹脂を適宜乾燥した後、表１に示した混合率でブレンドを行い、溶融押出、延伸、熱処理工程を経て製膜を行い、厚みが１２μｍのフィルムを得た。
【０１１１】
（実施例１）
本発明のフィルムの基材フィルムＡの原料として、ＰＥＴ−Ａ／粒子マスターＤ＝重量比９７．５／２．５の割合の混合樹脂を用い、ポリエステルＢとして、ＰＥＴ−Ａ／粒子マスターＡ＝重量比９９．５／０．５の割合の混合樹脂を用いた。それぞれのペレットを十分に真空乾燥した後、別々の押出機に供給して２８０℃で溶融させ、それぞれの濾過フィルターを得た後、スリット状の２層口金に導き、基材フィルムＡ層／ポリエステルＢ層の順に積層して、これを表面温度２５℃の冷却ドラムに巻き付けて冷却固化した。この間のシートと冷却ドラム表面との密着性を向上させるために、シート側にワイヤー電極を配して６ｋＶの直流電圧を引加した。このようにして得られた未延伸フィルムを９０℃に加熱して長手方向に３．１倍延伸し、一軸延伸フィルムとした。該フィルムをクリップで把持しテンター内に導き９５℃で幅方向に４．０倍延伸し、さらに２３８℃の雰囲気下で５秒間の熱処理を施し、フィルム厚み１２μｍの包装用フィルム（基材フィルムＡ／ポリエステルＢの積層厚み＝１１／１μｍ）を得た。
【０１１２】
次に、得られた包装用フィルムを５０℃に加熱したゴムロールを介して、ポリエステルＢ積層表面を窒素／炭酸ガスの混合ガス（窒素／炭酸ガス＝８５／１５）の雰囲気中で、４０Ｗ・ｍｉｎ／ｍ^２の処理条件でコロナ放電処理を施し、フィルムの濡れ張力を４５ｍＮ／ｍ以上にしてロール状に巻き取った。その時のフィルムの温度は３０℃であり、１０時間放置した後に小幅にスリットした。次に、小幅にスリットしたフィルムをフイルム走行装置を具備した真空蒸着装置内にセットし、１．００×１０^−２Ｐａの高真空にした後に、−２０℃の冷却金属ドラムを介して走行させた。この時、アルミニウム金属を加熱蒸発させながら、走行フィルムのコロナ放電処理面に凝集堆積させ、アルミニウムの蒸着薄膜層を形成して巻取った。蒸着後、真空蒸着装置内を常圧に戻して、巻取ったフィルムを巻き返し、４０℃の温度で２日間エージングして、蒸着フィルムを得た。この蒸着フィルムの無機薄膜の厚みは４５ｎｍであった。
【０１１３】
（実施例２）
本発明のフィルムの基材フィルムＡの原料として、ＰＥＮ−Ａ／粒子マスターＤ＝重量比９７．５／２．５の割合の混合樹脂を用い、ポリエステルＢとして、ＰＥＴ−Ａ／ＰＢＴ−Ａ／粒子マスターＡ＝重量比９４．０／５．０／１．０の割合の混合樹脂を用い、それぞれのペレットを十分に真空乾燥した後、別々の押出機に供給して２９０℃で溶融させ、それぞれの濾過フィルターを得た後、スリット状の２層口金に導き、基材フィルムＡ／ポリエステルＢの順に積層して、これを表面温度２５℃の冷却ドラムに巻き付けて冷却固化した。この間のシートと冷却ドラム表面との密着性を向上させるために、シート側にワイヤー電極を配して６ｋＶの直流電圧を引加した。このようにして得られた未延伸フィルムを１３５℃に加熱して長手方向に３．１倍延伸し、一軸延伸フィルムとした。該フィルムをクリップで把持して１００℃に加熱されたテンター内に導き、連続的に１４０℃に加熱された領域で幅方向に４．０倍延伸し、さらに２３８℃の雰囲気下で５秒間の熱処理を施し、フィルム厚み１２μｍの包装用フィルム（基材フィルムＡ／ポリエステルＢの積層厚み＝１１．９／０．１μｍ）を得た。包装用フィルムは実施例１と同様に蒸着して無機薄膜の厚み４５ｎｍの蒸着フィルムを得た。
【０１１４】
（実施例３）
本発明のフィルムの基材フィルムＡの原料として、ＰＥＴ−Ａ／ＰＢＴ−Ａ／ＰＥＥ−Ａ／粒子マスターＤ＝重量比７７．５／１９．０／１．０／２．５の割合の混合樹脂を用い、ポリエステルＢの原料として、ＰＥＴ−Ａ／粒子マスターＢ＝重量比９５．０／５．０の割合の混合樹脂を用いた。基材フィルムＡの混合ペレットは、ＰＥＴは１８０℃×４時間、ＰＢＴは１５０℃×４時間、ＰＥＥは７０℃×２４時間、十分真空乾燥を行い、ＰＥＴおよびＰＢＴは７０℃まで冷却した後、ＰＥＥを混合して用いたこと以外は、実施例１と同様な手法でフィルム厚み１２μｍの原反フィルム（基材フィルムＡ層／ポリエステルＢ層の積層厚み＝１０μｍ／２μｍからなる積層フィルム）を得た。該原反フィルムを用い、実施例１と同じ手法で無機薄膜の厚み４５ｎｍの本発明の蒸着フィルムを得た。
【０１１５】
（実施例４）
本発明のフィルムの基材フィルムＡの原料として、ＰＥＴ−Ａ／ＰＢＴ−Ａ／ＰＥＥ−Ｂ／粒子マスターＤ＝重量比７２．５／２０．０／５．０／２．５の割合の混合樹脂を用い、ポリエステルＢの原料として、ＰＥＴ−Ａ／粒子マスターＣ＝重量比８０．０／２０．０の割合の混合樹脂を用いた。基材フィルムＡ層の原料混合は実施例３と同様な手法で混合し、実施例１と同様な手法でフィルム厚み１２μｍの原反フィルム（基材フィルムＡ層／ポリエステルＢ層の積層厚み＝１１μｍ／１μｍからなる積層フィルム）を得た。また、実施例１と同じ手法で無機薄膜の厚み４５ｎｍの本発明の蒸着フィルムを得た。
【０１１６】
（実施例５）
本発明のフィルムの基材フィルムＡの原料として、ＰＥＴ−Ａ／粒子マスターＤ＝重量比９７．５／２．５の割合の混合樹脂を用い、ポリエステルＢとして、ＰＥＴ−Ａ／ＰＢＴ−Ａ／粒子マスターＡ＝重量比７７．０／２０．０／３．０の割合の混合樹脂を用いた。実施例１と同様な手法でフィルム厚み１２μｍの原反フィルム（基材フィルムＡ層／ポリエステルＢ層の積層厚み＝７μｍ／５μｍからなる積層フィルム）を得た。また、実施例１と同じ手法で無機薄膜の厚み４５ｎｍの本発明の包装用フィルムを得た。
【０１１７】
以上の蒸着用包装フィルムの品質評価結果を表１にまとめた。表１の結果からわかるように、実施例１〜４で得られた蒸着フィルムはガスバリア性、ハンドリング性、及び蒸着密着性に優れたものであった。
【０１１８】
（比較例１）
ポリエステルＢの組成をＰＥＴ−Ａ／粒子マスターＤ＝重量比９５．５／０．５の割合の混合樹脂を用い、実施例１と同様な手法でフィルム厚み１２μｍの原反フィルム（基材フィルムＡ層／ポリエステルＢ層の積層厚み＝６μｍ／６μｍからなる積層フィルム）を得た。また、実施例１と同じ手法で無機薄膜の厚み４５ｎｍの蒸着フィルムを得た。
【０１１９】
（比較例２）
ポリエステルＢの組成をＰＥＴ−Ａ／粒子マスターＡ＝重量比２０．０／８０．０の割合の混合樹脂を用い、実施例１と同様な手法でフィルム厚み１２μｍの原反フィルム（基材フィルムＡ層／ポリエステルＢ層の積層厚み＝１１μｍ／１μｍからなる積層フィルム）を得た。また、実施例１と同じ手法で無機薄膜の厚み４５ｎｍの蒸着フィルムを得た。
【０１２０】
（比較例３）
ポリエステルＢの組成をＰＥＴ−Ａ／ＰＢＴ−Ａ／粒子マスターＥ＝重量比２０．０／２０．０／６０．０の割合で混合した混合樹脂を用いた。実施例１と同様な手法でフィルム厚み１２μｍの原反フィルム（基材フィルムＡ層／ポリエステルＢ層の積層厚み＝１１μｍ／１μｍからなる積層フィルム）を得た。また、実施例１と同じ手法で無機薄膜の厚み４５ｎｍの蒸着フィルムを得た。比較例１〜３で得られた蒸着フィルムは、ガスバリア性が劣るフィルムで、いずれの蒸着フィルムも包装用フィルムとして好ましくなかった。
【０１２１】
【表１】

【０１２２】
【発明の効果】
本発明によれば、蒸着加工性、ガスバリア性に優れた包装用フィルムおよび蒸着フィルムを安定して提供することができる。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a packaging film excellent in vapor deposition processability and barrier properties against oxygen and water vapor (gas barrier properties), and a vapor deposition film using the same.
[0002]
[Prior art]
In order to preserve foods and medicines for a long period of time, it is necessary to perform packaging that is excellent in so-called gas barrier properties and has the effect of blocking the ingress of oxygen and water vapor that promote spoilage and deterioration from outside air. Conventionally, various gas barrier films have been used. In recent years, in the gas-barrier film packaging, there has been a strong demand for transparency in which the state of the contents can be confirmed, and various transparent gas-barrier films have been used (for example, see Patent Document 1). ).
[0003]
For example, as an opaque package having a high gas barrier property, a film package in which an aluminum foil is laminated is known (for example, see Patent Document 2). However, aluminum foil is inferior in flexibility to polymer films, and pinholes are generated by bending during processing, etc., and gas barrier properties are likely to decrease. Alternatives are desired.
[0004]
Further, as a transparent gas barrier film, a laminated film of a polyvinylidene chloride resin and an ethylene-vinyl alcohol copolymer resin is known (for example, see Patent Document 3). Further, it is known that a film formed of a metal compound film on the surface of a polymer film has good gas barrier properties and transparency (for example, see Patent Document 4). However, there were the following problems.
[0005]
A laminated film of a polyvinylidene chloride resin and an ethylene-vinyl alcohol copolymer resin does not have sufficient gas barrier properties against oxygen and water vapor, and the decrease is remarkable particularly in a sterilization treatment at a high temperature. Furthermore, polyvinylidene chloride generates chlorine gas during incineration, and there is a concern that it may adversely affect the global environment.
[0006]
Furthermore, films formed with a silicon oxide film or an aluminum oxide film by vapor deposition have good gas barrier properties, but in recent years, their eating habits have been enriched, and various foods and confectioneries have appeared on the market. Sex is becoming more important. Along with this, packaging materials are required to further improve properties such as gas barrier properties. In particular, in the packaging of snacks, foods and the like, a high gas barrier property capable of preventing oxidation and wetness of the packaged contents for a long period of time has been demanded in order to secure good quality of freshly manufactured products for a long period of time.
[0007]
In order to meet these requirements, for example, a transparent gas barrier film in which a specific copolymerized polyester component is blended is proposed (for example, see Patent Document 5).
On the other hand, there has been proposed a film for a magnetic recording medium which is excellent in abrasion resistance and running properties by containing aluminum silicate particles having a true spherical shape and a monodispersed particle size distribution (see Patent Document 6).
[0008]
[Patent Document 1]
JP-A-11-070611
[0009]
[Patent Document 2]
JP 2001-129914 A
[0010]
[Patent Document 3]
JP 2000-263729 A
[0011]
[Patent Document 4]
JP 08-072193 A
[0012]
[Patent Document 5]
JP 08-231836 A
[0013]
[Patent Document 6]
JP-A-08-134332
[0014]
[Problems to be solved by the invention]
However, in the inventions described in these documents, although the gas barrier properties are certainly improved, they have not reached the high gas barrier properties required in recent years.
[0015]
Therefore, the object of the present invention is to solve the problems of the prior art, to significantly improve the gas barrier properties of oxygen and water vapor of the vapor deposition film, and to provide a vapor deposition film that exhibits excellent gas barrier properties. It is to provide a stable supply.
[0016]
[Means for Solving the Problems]
In order to achieve the above object, the present invention has the following configurations. That is, a packaging film characterized in that a polyester B layer containing 0.005 to 0.5% by weight of aluminum silicate particles is laminated on at least one side of the polyester film A at 0.01 to 5 μm.
[0017]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described in detail.
The base film A and / or B layer in the present invention is made of polyester. This polyester is a high molecular weight substance constituted by an ester bond, and is preferably a polyester mainly composed of an ethylene terephthalate unit and / or an ethylene naphthalate unit. This is because by using the polyester having the composition, both heat resistance and workability can be achieved. Here, being a main constituent means that the constituent ratio of ethylene terephthalate unit and / or ethylene naphthalate unit in the polyester is 60 mol% or more.
[0018]
The polyester is preferably polymerized from a dicarboxylic acid component mainly containing terephthalic acid and / or 2,6-naphthalenedicarboxylic acid and a glycol component mainly containing ethylene glycol. Examples thereof include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, diphenyldicarboxylic acid, diphenylsulfonedicarboxylic acid, diphenoxyethanedicarboxylic acid, 5-sodium sulfoisophthalic acid, and phthalic acid, oxalic acid, and succinic acid , Adipic acid, sebacic acid, dimer acid, maleic acid, aliphatic dicarboxylic acids such as fumaric acid, alicyclic dicarboxylic acids such as cyclohexyne dicarboxylic acid, and oxycarboxylic acids such as p-oxybenzoic acid. it can. Among these, in the polyester of the present invention, the ratio of terephthalic acid and / or naphthalenedicarboxylic acid to be reduced is preferably 70 mol% or more, more preferably 85 mol% or more, and particularly preferably 95 mol% or more. It is preferable because it can easily obtain productivity, cost, adhesiveness to a deposited film, and excellent gas barrier properties.
[0019]
On the other hand, examples of the glycol component include aliphatic glycols such as ethylene glycol, propanediol, butanediol, pentanediol, hexanediol, and neopentyl glycol; alicyclic glycols such as cyclohexanedimethanol; and aromatic compounds such as bisphenol A and bisphenol S. Group glycol, diethylene glycol, and the like can be used. Of these, the proportion of ethylene glycol to be added is preferably at least 60 mol%, more preferably at least 70 mol%, particularly preferably at least 85 mol%, heat resistance, productivity, cost, adhesion to the deposited film, It is preferable because excellent gas barrier properties are easily obtained.
[0020]
Two or more of these dicarboxylic acid components and glycol components may be used in combination. Furthermore, as long as the effects of the present invention are not impaired, polyesters used in the present invention may be those obtained by copolymerizing polyfunctional compounds such as trimellitic acid, trimesic acid, and trimethylolpropane.
[0021]
The polyester constituting the polyester film used in the present invention may be a single type of polyester or a blend of two or more types of polyester. However, from the viewpoint of improving processability, polyethylene terephthalate and polyethylene terephthalate are preferably used. It is a blend of phthalates.
[0022]
The polyester used in the present invention has an intrinsic viscosity of preferably 0.50 dl / g or more, more preferably 0.55 dl / g or more, particularly preferably 0.50 dl / g or more, in order to further improve the adhesiveness and the film-forming stability. 0.60 dl / g or more. If the intrinsic viscosity is less than 0.50 dl / g, there is a possibility that the adhesion to the deposited film is reduced.
[0023]
The catalyst for producing the polyester used in the present invention is not particularly limited, but includes alkaline earth metal compounds, manganese compounds, cobalt compounds, aluminum compounds, antimony compounds, titanium compounds, titanium / silicon composite oxides, germanium compounds, and the like. Can be used. Among them, titanium compounds, titanium / silicon composite oxides, and germanium compounds are preferred from the viewpoint of catalytic activity.
[0024]
Other polyesters can be blended with the polyester film as long as the effects of the present invention are not impaired. As other polyesters, for example, polyethylene terephthalate (PET), polypropylene terephthalate (PPT), polybutylene terephthalate (PBT), polyhexane terephthalate (PHT), polyethylene naphthalate (PEN), polycyclohexane dimethylene terephthalate (PCT), poly Hydroxybenzoate (PHB) and copolymer resins thereof can be exemplified.
[0025]
The polyester resin used for the base film A of the present invention preferably contains a polyoxyalkylene glycol component from the viewpoint of impact resistance and pinhole resistance. From the viewpoint of the transparency of the film, the content of the polyoxyalkylene glycol is 0.1 to 5% by weight. If the content exceeds 5% by weight, the transparency of the film deteriorates, which is not preferable. Particularly preferably, it is 0.1 to 3% by weight.
[0026]
Here, as polyoxyalkylene glycol, polyethylene glycol, polytrimethylene glycol, polytetramethylene glycol, polypentamethylene glycol, polyhexamethylene glycol, polyheptamethylene glycol, polyoctamethylene glycol, polydecamethylene glycol, poly1- Methyl dimethylene glycol, poly 2-methyl trimethylene glycol and the like can be mentioned. Among them, polydimethylene glycol, polytrimethylene glycol and polytetramethylene glycol are preferred. Polytetramethylene glycol is particularly preferred from the viewpoint of pinhole resistance. Further, from the viewpoint of suppressing the dispersibility of the polyoxymethylene glycol in the polyester and the haze of the film to be low, the molecular weight of the polyoxymethylene glycol is preferably from 500 to 4,000. More preferably, the molecular weight is particularly preferably 800 to 1500.
[0027]
The polyoxyalkylene glycol exists in the polyester as a polyetherester which is a block copolymer of a polyester comprising a polyoxyalkylene glycol and a dicarboxylic acid component such as terephthalic acid and polyethylene terephthalate or polybutylene terephthalate. Is particularly preferable since pinhole resistance and impact resistance are particularly improved. In particular, when the glass transition point of the polyetherester is -120 to 0 ° C, the effect of improving the pinhole resistance is remarkably improved, and the glass transition point is more preferably -120 to -30 ° C.
[0028]
In the packaging film of the present invention, the aluminum silicate particles need to be contained in the polyester B layer in an amount of 0.005 to 0.5% by weight, more preferably 0.01 to 0.1% by weight. Is good. If the particle content is less than the lower limit, the handleability of the film is liable to deteriorate, which is not preferable. Conversely, if the upper limit is exceeded, the flaw resistance is deteriorated, and this may cause a defect in vapor deposition, and the gas barrier property is liable to deteriorate.
[0029]
The layer thickness of the polyester B layer must be 0.01 to 5 μm, preferably 0.05 to 5 μm, and more preferably 0.1 to 5 μm. If the lamination thickness is less than the lower limit, it is difficult to obtain excellent vapor deposition barrier properties. Conversely, if the lamination thickness exceeds the upper limit, it depends on the thickness of the base film, but is not preferable in terms of cost and vapor deposition balance.
[0030]
The volume average particle diameter of the aluminum silicate particles in the present invention is in the range of 0.005 to 2 μm, preferably in the range of 0.01 to 1.0 μm. If the volume average particle diameter of the aluminum silicate exceeds 2 μm, the surface projections become too large, and when vapor deposition is performed, it causes vapor deposition defects and deteriorates gas barrier properties, which is not preferable. Conversely, if it is less than 0.005 μm, sufficient projections cannot be obtained, and the running property during vapor deposition is undesirably reduced.
[0031]
In this case, the relative standard deviation σ of the particle size distribution is 0.5 or less, preferably 0.3 or less, particularly preferably 0.15 or less.
[0032]
(Equation 1)

[0033]
Here, σ represents the relative standard deviation, D represents the number average particle diameter (μm), Di represents the particle diameter (μm), and n represents the number of particles (pieces). If the relative standard deviation is larger than 0.5, coarse projections are likely to be formed, and it is difficult to obtain a uniform surface, which causes a defect in vapor deposition and lowers gas barrier properties.
[0034]
In addition, the surface of the aluminum silicate particles of the present invention is preferably made of aluminum silicate. As a method for producing such an aluminum silicate, for example, a silicate of an alkali metal, ammonium or an organic base and an alkali-soluble aluminum compound are simultaneously added to an aqueous alkali solution having a pH of 10 or more and reacted. Thereby, target particles can be generated. At this time, in order to generate particles having a larger specific surface area, it is more preferable to adjust the reaction solution so that the molar ratio of silicon atoms / aluminum atoms is 0.25 to 10.
[0035]
In addition, when the reaction is performed after dispersing the seed particles in an alkaline aqueous solution having a pH of 9 or more, the particles grow with the seed particles as nuclei, so that the particle diameter can be easily controlled. At this time, the seed particles preferably have a relative standard deviation σ of 0.5 or less and a ratio of major axis / minor axis of the particles of 1.0 to 1.2, and control the particle growth reaction. Since silica particles are easily used, silica particles are preferably used.
[0036]
Thus, as the aluminum silicate particles in the present invention, aluminum silicate-coated particles whose particle surfaces are coated with aluminum silicate can also be used. In addition, the thickness of the aluminum silicate layer at this time is preferably 0.01 to 0.3 μm, more preferably 0.05 to 0.2 μm, and particularly preferably 0.08 to 0.2 μm.
[0037]
As the composition of such aluminum silicate particles, the molar ratio of silicon atoms / aluminum atoms is preferably 0.25 to 10, and more preferably 0.5 from the viewpoint of stability of particle diameter control in the granulation process. ５5.0.
[0038]
The specific surface area is preferably in a range that satisfies the following expression, and is preferably porous.
[0039]
S ≧ 3.5 / Dw
Here, Dw: volume average particle diameter (μm) S: specific surface area (m ² / G). → The upper limit is not particularly limited, but is preferably 1,000 or less.
Such aluminum silicate particles are anionic surfactants such as sodium dodecylbenzenesulfonate, sodium lauryl sulfate, sodium dialkylsulfosuccinate, and formalin condensate of naphthalenesulfonic acid, as long as the effects of the present invention are not impaired. Nonionic surfactants such as polyoxynonylphenol ether, polyethylene glycol monostearate and sorbitan monostearate; water-soluble synthetic polymers such as polyvinyl alcohol, polyvinylpyrrolidone and polyethylene glycol; and water-soluble natural materials such as gelatin and starch. Polymers, water-soluble semi-synthetic polymers such as carboxymethylcellulose, silane-based or titanium-based coupling agents, and phosphorous compounds such as phosphoric acid, phosphorous acid, phosphonic acid, and derivatives thereof. It can also be used those treated.
[0040]
Further, particles other than aluminum silicate particles (hereinafter referred to as particles A) may be used in combination within a range not to impair the effects of the present invention. At this time, the volume average particle diameter of the particles A is preferably 0.005 to 1.0 μm, more preferably 0.01 to 0.5 μm, and further 0.1 μm or more than the aluminum silicate particles. Preferably, it is small. The content is preferably 0.005 to 3.0% by weight, more preferably 0.01 to 2.0% by weight, based on the polyester. The specific surface area of the particles A is 10 m ² / G or more, more preferably 30 m ² / G or more, especially 100 m ² / G or more. The type of the particles A in the present invention is not particularly limited as long as the Mohs hardness is 6 or more, and examples thereof include silicon oxide, titanium oxide, zirconium oxide, aluminum oxide, spinel, and iron oxide. Among these particles, zirconium oxide and aluminum oxide are particularly preferred.
[0041]
Furthermore, it is also preferable to add particles (hereinafter, referred to as particles B) in addition to the above particles. The volume average particle diameter of the particles B is preferably 0.05 to 2.0 μm, and more preferably the difference in volume average particle diameter from aluminum silicate is 0.2 μm or less. The content is preferably from 0.005 to 0.3% by weight. The type of the particles B is not particularly limited as long as the particles have a Mohs hardness of less than 4, and examples thereof include inorganic particles such as kaolinite, talc, calcium sulfate, barium sulfate, calcium carbonate, and zinc sulfide. Calcium carbonate is particularly preferred. In addition to such inorganic particles, crosslinked organic polymer particles can also be used. As such organic polymer particles, any particles may be used as long as at least a part thereof is insoluble in polyester. As the material of such particles, various materials such as polyimide, polyamide imide, polymethyl methacrylate, formaldehyde resin, phenol resin, polystyrene, polysilsesquioxoic acid, so-called silicone resin can be used, Particularly preferred are vinyl-based crosslinked polymer particles having high properties and easily obtaining particles having a uniform particle size distribution.
[0042]
Here, the vinyl-based crosslinked polymer particles are a monovinyl compound a having only one aliphatic unsaturated bond in the molecule, and a compound b having two or more aliphatic unsaturated bonds in the molecule as a crosslinking component. Is preferred.
[0043]
Examples of the monovinyl compound a in the copolymer include monovinyl compounds such as styrene, α-methylstyrene, fluorostyrene, vinylpyrine, and ethylvinylbenzene, acrylonitrile, vinyl cyanide compounds such as methacrylonitrile, methyl acrylate, and ethyl acrylate. Acrylate monomers such as propyl acrylate, hexadecyl acrylate, octyl acrylate, dodecyl acrylate, hexadecyl acrylate, glycidyl acrylate, N, N'-dimethylaminoethyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, butyl Methacrylate, sec-butyl methacrylate, acrylic methacrylate, phenyl methacrylate Methacrylate monomers such as methacrylate, benzyl methacrylate, 2-ethylhexyl methacrylate, 2-hydroxyethyl methacrylate, glycyl methacrylate, N, N'-dimethylaminoethyl methacrylate, acrylic acid, methacrylic acid, maleic acid, itaconic acid For example, mono- or dicarboxylic acids and acid anhydrides of dicarboxylic acids, and amide monomers such as acrylamide and methacrylamide can be used. As the compound a, styrene, ethylvinylbenzene, methyl methacrylate and the like are preferably used.
[0044]
Examples of the compound b include a divinylbenzene compound, or trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, or ethylene glycol diacrylate, ethylene glycol dimethacrylate, polyethylene glycol diacrylate, polyethylene glycol dimethacrylate, 1,3-butylene. Examples include polyacrylates and methacrylates such as glycol diacrylate and 1,3-butylene glycol dimethacrylate.
[0045]
Among compound b, it is particularly preferable to use divinylbenzene, ethylene glycol dimethacrylate, or trimethylolpropane trimethacrylate.
[0046]
Preferred examples of the composition of the vinyl-based crosslinked polymer particles include divinylbenzene polymer, ethylvinylbenzene-divinylbenzene copolymer, styrene-divinylbenzene copolymer, ethylene glycol dimethacrylate polymer, and styrene-ethylene glycol. Examples thereof include a dimethacrylate copolymer and a methyl methacrylate-divinylbenzene copolymer. However, the copolymer is not limited to these examples. For example, a copolymer of three or more components such as a styrene-ethylvinylbenzene-divinylbenzene copolymer and a styrene-ethylene glycol dimethacrylate-methyl methacrylate copolymer may be used. Is also good.
[0047]
For example, there is a method for producing such vinyl polymer particles by mixing the compounds a and b and performing the following emulsion polymerization.
(A) A soap-free polymerization method, that is, a method in which no emulsifier is used or polymerization is performed using an extremely small amount of an emulsifier.
(B) A seed method in which polymer particles are added to a polymerization system prior to emulsion polymerization and emulsion polymerization is performed.
(C) A core-shell polymerization method in which a part of the monomer component is emulsion-polymerized and the remaining monomer is polymerized in the polymerization system.
(D) A polymerization method using Eugelstatt or the like described in JP-A-54-97582.
(E) A polymerization method using no swelling aid in the method of (d).
[0048]
Here, the organic polymer particles have a heat decomposition temperature of 350 ° C. or higher at a thermal decomposition temperature (10% weight loss temperature, 10 ° C./min in a nitrogen gas stream, by a thermobalance) at the time of producing the polyester composition. The particles are preferably not aggregated at the time of melt molding or reuse and recovery of the molded article, and are preferable in that the surface uniformity, abrasion resistance and the like of the film are not reduced, more preferably 360 ° C or higher, particularly preferably 370 ° C or higher. . Such an organic polymer particle has a degree of crosslinking defined by the following formula: 10% of the degree of crosslinking = the weight of the crosslinking component of the raw material monomer / the total weight of the raw material monomer × 100 (%) with respect to all the organic components constituting the particle. When the content is at least as high, the dispersibility of the particles in a polyester film is good, and the content is more preferably 30% or more, and particularly preferably 55% or more.
[0049]
In mixing the aluminum silicate particles into the polyester in the present invention, besides a method of directly adding the particles to the polymerization reaction system, for example, a method of kneading the particles into a molten polyester is also possible. The timing of addition in the former polymerization reaction system is arbitrary, but is preferably from before the transesterification reaction or after the esterification reaction to before the start of the pressure reduction in the polycondensation reaction. In the case of the latter kneading, a method of drying and kneading the particles into the polyester or a method of directly kneading while reducing the pressure in a slurry state may be used.
[0050]
The composition of the polyester B layer thus obtained may be used by blending with another polyester such as a polyester for dilution according to the purpose.
[0051]
Further, in the packaging film of the present invention, the polyester B layer formed on at least one side of the base film layer is composed of 95 to 60% by weight of an ethylene terephthalate component and 5 to 40% by weight from the viewpoint of vapor deposition film adhesion and gas barrier properties. It is preferable that the polyester is a polyester comprising a butylene terephthalate component by weight. It is more preferably 5 to 30% by weight, and particularly preferably 5 to 25% by weight from the viewpoint of transparency and dimensional stability.
[0052]
Further, the laminated thickness of the polyester B layer of the present invention needs to be 0.01 to 5 μm. If the thickness is less than 0.01 μm, it is difficult to obtain excellent adhesion to a deposited film and gas barrier properties. Conversely, if the thickness exceeds 5 μm, it is not preferable in terms of productivity. More preferably, it is 0.05 to 5 μm, and still more preferably 0.1 to 5 μm.
[0053]
The method of mixing the ethylene terephthalate component and the butylene terephthalate component of the polyester B layer is as follows. In the polymerization step, polycondensation is carried out by esterification or transesterification with terephthalic acid in the presence of ethylene glycol and 1,4-butanediol as glycol components. And a method of separately polymerizing and pelletizing polyethylene terephthalate and polybutylene terephthalate, blending them into a predetermined mixing ratio at the time of film formation, drying and mixing by performing melt extrusion. Among them, the latter method of mixing separately polymerized polyesters is preferably used. In order to suppress the transesterification reaction during the melt extrusion, a solid or liquid phosphorus compound may be added for the purpose of deactivating the polymerization catalyst in the polyester resin.
[0054]
Further, the polyester resin constituting the polyester film of the present invention may be copolymerized with components other than the ethylene terephthalate component and the butylene terephthalate component, and in order to impart moldability, isophthalic acid, dimer acid, and 1,3-dodecadionic acid. And the like can be used as a preferable copolymer component. Of course, a polyoxyalkylene glycol component may be previously copolymerized with a polyester resin to form a film, or a polyether ester may be separately prepared and used by blending with a polyester resin.
[0055]
The polyester film of the present invention preferably has only one melting point measured by a differential scanning calorimeter from the viewpoint of heat resistance, vapor deposition property, and dimensional stability. The melting point is particularly preferably between 245 and 260 ° C. Usually, when polyethylene terephthalate and polybutylene terephthalate are blended, two melting points are measured due to each polyester, but when melting and extruding, polyester is alloyed on the order of nanometers to make the melting point one. By suppressing transesterification, excellent vapor deposition adhesion can be achieved, and as a result, excellent gas barrier properties can be achieved.
[0056]
When polymerizing the polyester of the present invention, a reaction catalyst and a color inhibitor can be appropriately selected and used. Examples of the reaction catalyst include an alkali metal compound, an alkaline earth metal compound, a zinc compound, a lead compound, and a manganese compound. , A cobalt compound, an aluminum compound, an antimony compound, a titanium compound, a germanium compound, and the like, and a coloring inhibitor such as a phosphorus compound can be used, but the present invention is not limited thereto. It is preferable to use an alkali metal compound and / or an alkaline earth metal compound for the reaction catalyst from the viewpoint of the content removal property.
[0057]
Regarding the addition of the polymerization catalyst, it is preferable to add an antimony compound, a germanium compound and / or a titanium compound as a polymerization catalyst at any stage before the production of the polyester is completed. As such a method, for example, in the case of a germanium compound, for example, a method of adding a germanium compound powder as it is, or, as described in JP-B-54-22234, glycol which is a starting material of a polyester, A method in which a germanium compound is dissolved and added to the components can be used.
[0058]
Here, as the germanium compound, for example, germanium dioxide, germanium hydroxide hydrate or germanium tetramethoxide, germanium alkoxide compounds such as ethylene glycoloxide, germanium phenoxide compounds, germanium phosphate, phosphorus such as germanium phosphite An acid-containing germanium compound, germanium acetate, or the like can be used. Among them, germanium dioxide is preferably used, and amorphous germanium dioxide is particularly preferably used.
[0059]
The antimony compound is not particularly limited, and for example, an oxide such as antimony trioxide, antimony acetate and the like are used.
[0060]
The titanium compound is not particularly limited, but is preferably a monobutyl titanate or dibutyl titanate, or a titanium tetraalkoxide such as titanium tetraethoxide or titanium tetrabutoxide.
[0061]
For example, when producing polyethylene terephthalate, when germanium dioxide is added as a catalyst, a terephthalic acid component and an ethylene glycol component are subjected to a transesterification or esterification reaction, and then germanium dioxide and a phosphorus compound are added. A method of obtaining a polymer containing germanium element by polycondensation under reduced pressure until the content of diethylene glycol becomes constant is preferably used.
[0062]
The laminated film of the present invention can be formed, for example, by the following method.
After the polyester composition pellets are sufficiently dried, they are immediately supplied to an extruder. The pellet is melted at 260 to 350 ° C., extruded into a sheet from a die, cooled and solidified on a casting roll to obtain an unstretched film. Next, it is preferable to biaxially stretch the unstretched film. As the stretching method, a sequential biaxial stretching method, a simultaneous biaxial stretching method, a method of stretching the film thus biaxially stretched again, or the like may be used. Although it depends on the composition of the polyester, for example, in order to obtain a sufficient elastic modulus as a film for a magnetic recording medium, it is preferable that the final stretch area ratio (longitudinal ratio × lateral ratio) is 6 or more.
[0063]
Further, in order to keep the heat shrinkage of the film small, it is preferable to perform a heat treatment at a temperature of 150 to 260 ° C. for about 0.1 to 60 seconds.
[0064]
Particles other than aluminum silicate particles can also be added to the polyester B layer of the packaging film in the present invention. Such particles are preferably internal particles and external particles having an average particle diameter of 0.01 to 2 μm.
[0065]
Examples of the internal particles include internal particles containing a lithium element described in JP-A-48-61556, and internal particles containing a lithium element, a calcium element, and a phosphorus element described in JP-A-53-41355. Techniques such as lithium compound and internal particles of lithium compound and calcium compound described in JP-A-54-90397 can be employed. Further, other particles such as internal particles containing at least one of an alkali metal element or an alkaline earth metal element described in JP-A-59-204617 as a part of a component may be used in combination.
[0066]
As the inorganic particles of the internal particles, for example, organic particles of external particles such as wet and dry silica, colloidal silica, aluminum silicate, titanium oxide, calcium carbonate, calcium phosphate, barium sulfate, aluminum oxide, mica, kaolin, clay, etc. Can be used particles composed of styrene, silicone, acrylic acid, methacrylic acid, polyester, divinyl compound and the like. Among them, it is preferable to use inorganic particles such as wet and dry silica and alumina and particles containing styrene, silicone, acrylic acid, methacrylic acid, polyester, divinylbenzene and the like as constituent components. Further, two or more of these internal particles and external particles may be used in combination. Among these, inorganic particles as external particles can be preferably used, and dry or wet silica is particularly preferably used. Further, the addition amount of the particles is more preferably 0.01 to 0.1% by weight from the viewpoint of gas barrier properties. More preferably, it is 0.01 to 0.05% by weight. When the addition amount of the particles is more than 0.5% by weight, a deposition defect may occur in the deposition layer when the deposition is performed, and the gas barrier property may decrease.
[0067]
In the packaging film of the present invention, the center line average surface roughness (Ra) of the surface on the inorganic thin film forming side (referred to as a deposited film forming surface) of the laminated film is preferably in the range of 0.005 to 0.030 μm. More preferably, it is 0.008 to 0.025 μm, and still more preferably 0.01 to 0.02 μm. By setting the Ra of the surface on which the vapor-deposited film is formed to be in the above range, good film handling properties (slipperiness) and further excellent workability can be obtained. That is, it is not preferable that Ra is less than 0.005 μm because the handling property of the film is apt to deteriorate. If Ra exceeds 0.03 μm, scratch resistance is deteriorated and defects in deposition are apt to occur during deposition, which is not preferable. The method for setting Ra to the above range is not particularly limited, but is preferably a method in which particles are contained in the base film layer (A layer), and the unevenness of the drum surface is transferred to the film surface by contacting the metal drum with a satin pattern. It may be a method to make it.
[0068]
Further, Ra of the film surface opposite to the surface on which the deposited film is formed (referred to as a non-deposited surface) is preferably from 0.008 to 0.05 μm, more preferably from 0.01 to 0.03 μm. If the Ra of the non-deposited surface exceeds 0.05 μm, the slipperiness is too high, and the deposition characteristics and workability such as the deterioration of the handling characteristics are undesirably deteriorated. The difference ([Delta] Ra) between Ra on the non-deposited surface and Ra on the deposited film forming surface is preferably 0.003 to 0.045 [mu] m, and more preferably 0.005 to 0.045 [mu] m.
[0069]
In the packaging film of the present invention, the plane orientation coefficient (fn) of the laminated film is preferably in the range of 0.155 to 0.180, and more preferably in the range of 0.1625 to 0.175. When fn is less than 0.155, the orientation of the film is reduced, so that the film is liable to elongate with a decrease in strength or an external force. Conversely, if it exceeds 0.180, unevenness in physical properties in the width direction of the film, whitening and the like are likely to occur, which is not preferable.
[0070]
Further, in the packaging film of the present invention, the heat shrinkage of the laminated film when heated at 150 ° C. for 30 minutes is 0.5 to 2% in the longitudinal direction of the film, and −1.2 to 0.2 in the width direction. It is preferably in the range of 5%, more preferably 1-2% in the longitudinal direction of the film and -1 to 0% in the width direction. When the heat shrinkage ratio is more than 2% in the longitudinal direction of the film and more than 0.5% in the width direction, or less than -1.2% in the width direction, during a process in which an external force such as a vapor deposition, a lamination or a printing process is applied. It is not preferable because the dimensional change tends to increase. It is preferable that the heat shrinkage when heated at 150 ° C. for 30 minutes in the longitudinal direction is as small as possible, but since it has about 0.5%, the lower limit of the heat shrinkage in the longitudinal direction is substantially 0.5%. is there. Here, a minus (-) value of the heat shrinkage indicates elongation.
[0071]
Furthermore, the thickness of the packaging film in the present invention is not particularly limited, but is preferably 1 to 300 μm, more preferably 5 to 100 μm.
[0072]
In order to produce the packaging film of the present invention, it is necessary to form an inorganic thin film by vapor deposition on the surface of the above laminated film on the other laminated side of the base film layer (layer A). At this time, increasing the surface wetting tension to 35 mN / m or more by performing corona discharge treatment on the surface to be vapor-deposited can be preferably employed to improve the adhesion of the vapor-deposited inorganic thin film. Atmosphere gas at the time of the corona discharge treatment at this time may be any of air, carbon dioxide, or a mixed system of nitrogen / carbon dioxide, and in particular, a mixed gas of carbon dioxide or nitrogen / carbon dioxide (volume ratio = 95/5 to 5/5). It is preferable to perform corona treatment in (50/50) because the wetting tension on the film surface increases to 35 mN / m or more.
[0073]
An inorganic thin film is formed on the surface subjected to the corona discharge treatment by vapor deposition. As a material constituting the inorganic thin film, aluminum and / or a metal oxide such as aluminum, silicon, zinc, and magnesium are preferable. Among metal oxides, aluminum oxide is more preferable in terms of gas barrier performance and cost. These metal oxides may be used singly, or a mixture of a plurality of them, or a metal oxide partially remaining.
[0074]
As a method of forming these inorganic thin films by vapor deposition, a normal vacuum vapor deposition method can be used, but ion plating, sputtering, a method of activating vapors by plasma, or the like can also be used. As a method of forming a metal oxide film, a method of depositing a metal oxide by direct evaporation may be used, but a method of reactive vapor deposition in an oxidizing atmosphere is more preferable from the viewpoint of productivity. Further, a chemical vapor deposition method (so-called CVD method) can also be used as a deposition method in a broad sense. In order to obtain an oxidizing atmosphere, a required amount of oxygen gas alone or a gas obtained by diluting oxygen gas with an inert gas may be introduced into a vacuum evaporation machine. The inert gas refers to a rare gas such as argon or helium, a nitrogen gas, or a mixed gas thereof. Reactive deposition is performed by a technique in which a metal or metal oxide is evaporated from an evaporation source in such an oxidizing atmosphere to cause an oxidation reaction near a base film to form an inorganic thin film on the base film. Examples of the evaporation source for these include a board type of a resistance heating system, a crucible type by radiation or high frequency heating, and a system by electron beam heating, but are not particularly limited.
[0075]
When the inorganic thin film is made of a metal oxide, it is most preferably a complete oxide. However, in general, when attempting to form a complete oxide, the probability of forming an excessively oxidized portion is high, and the gas barrier performance of the excessively oxidized portion is inferior, and it is difficult to obtain high gas barrier performance as a whole. Therefore, an incomplete oxide film in which some metal components remain may be used.
[0076]
The light transmittance of the vapor-deposited film is preferably 70% or more, more preferably 80% or more, and further preferably 85% or more, from the viewpoint of confirming the quality of the contents when used as a packaging bag. The upper limit of the light transmittance is limited by the light transmittance of the base film layer (layer A), and the upper limit (92%) of the light transmittance of a general polyester film is substantially equal to the substantial light transmittance. It becomes the upper limit.
[0077]
The thickness of the inorganic thin film is preferably 20 to 50 nm in the case of an aluminum thin film, and a film having an optical density (logarithm of the reciprocal of light transmittance) of about 1.5 to 3.0 is deposited. In the case of a metal oxide, a thickness of preferably 5 to 100 nm, more preferably 8 to 50 nm is used in terms of gas barrier performance and flexibility. If the film thickness is less than 5 nm, the gas barrier performance is not sufficient. When the film thickness exceeds 100 nm, due to the latent heat of aggregation of the metal oxide during vapor deposition, the heat loss of the film's extreme surface melting and whitening occurs, and the flexibility of the vapor-deposited film deteriorates. This is not preferable because cracks and peeling of the deposited thin film are likely to occur.
[0078]
In the packaging film of the present invention, another resin can be laminated on the surface on which the inorganic thin film is deposited. As the other resin to be laminated, a polyolefin resin, a nylon resin, a polyethylene terephthalate resin, or the like is preferable, and a laminate of a biaxially stretched film or a laminate of a non-stretched film may be used. When laminating as a heat seal layer, a non-stretched film of a polyolefin resin is preferred, and these films are preferably laminated by an extrusion laminating method or an adhesive. The vapor-deposited film in this case is used as a packaging bag, with the heat-sealing layers overlapped and sealed.
[0079]
The packaging film of the present invention has excellent gas barrier properties while maintaining low moisture absorption, dimensional stability, flatness, and transparency, which are the characteristics of the polyester film, so that it is preferably used for food packaging and the like. it can.
[0080]
In each film layer constituting the film of the present invention, if necessary, flame retardants, heat stabilizers, antioxidants, ultraviolet absorbers, antistatic agents, pigments, dyes, organic lubricants such as fatty acid esters, waxes, etc. Alternatively, an antifoaming agent such as polysiloxane can be blended.
[0081]
In the packaging film for vapor deposition of the present invention, the laminated film before forming the inorganic thin film is made of a polyester A (melting point of 220 to 270 ° C.) described in JP-A-9-24588, for example, using different kinds of polymers. The polyester B (150 ° C. to 245 ° C.) layer is laminated on at least one side of the layer to form a laminated structure in which the melting point difference between the A layer and the B layer is 5 to 60 ° C. The form of the laminated film is not particularly limited. For example, when the base film layer (A layer) / polyester layer (B layer) / is represented by A and B, respectively, A / B and B / A / Although a lamination form such as B can be mentioned, an A / B lamination form is preferable to satisfy both the blocking property and the vapor deposition property. The lamination thickness ratio may be arbitrarily set. Further, other layers may be laminated, for example, an antistatic layer, a mat layer, a hard coat layer, a lubricious coat layer, a lubricious adhesive layer, an adhesive layer, and the like may be laminated as necessary.
[0082]
In the present invention, the method for producing the laminated film before forming the inorganic thin film is not particularly limited. Here, a polyester film and a polyester film containing aluminum silicate are used as a resin constituting each of the base film (A) and the polyester layer (B layer), and a biaxially stretched film is taken as an example. explain.
[0083]
After drying polyester A and polyester B using a normal hopper drier, paddle drier, vacuum dryer, etc., they are supplied to separate extruders, respectively, melted at 200 to 320 ° C., and formed into two slit-like layers. The mixture is guided to a die, extruded into a two-layer laminated sheet, and quenched to obtain a laminated unstretched film of polyester A / polyester B. The use of the T-die method is preferable because a film having a uniform thickness can be obtained by using a so-called electrostatic application contact method during rapid cooling. Next, the unstretched film is biaxially stretched simultaneously or sequentially. In the case of sequential biaxial stretching, the stretching order may be the order of the film in the longitudinal direction and the width direction, but may be the reverse order. Further, in the sequential biaxial stretching, the stretching in the longitudinal direction or the width direction can be performed twice or more. The stretching method is not particularly limited, and methods such as roll stretching and tenter stretching are applied, and the shape may be any shape such as a flat shape and a tube shape. The stretching ratio in the longitudinal direction and the width direction of the film can be arbitrarily set according to the desired deposition suitability, orientation, and the like, but is preferably 1.5 to 6.0 times. The stretching temperature may be any temperature as long as it is in the range from the glass transition temperature of the polyester to the crystallization temperature, but it is usually preferably from 30 to 150 ° C. Furthermore, the film can be subjected to a heat treatment after the biaxial stretching. The heat treatment temperature may be any temperature equal to or lower than the melting point of polyester A, but is preferably 200 to 240 ° C. The heat treatment may be performed while relaxing the film in the longitudinal direction and / or the width direction.
[0084]
The laminated film thus obtained is then subjected to a vapor deposition treatment.Before this vapor deposition treatment, the surface to be vapor-deposited is subjected to an adhesion promoting treatment, for example, a corona discharge treatment in air or another atmosphere, A flame treatment, an ultraviolet treatment, or the like may be applied. In the case of the corona discharge treatment, the atmospheric gas may be any of air, carbon dioxide, or a mixed system of nitrogen / carbon dioxide, and particularly, a mixed gas of carbon dioxide or nitrogen / carbon dioxide (volume ratio = 95/5 to 50/50). It is preferable to perform the corona treatment in step 50) because the wetting tension on the film surface increases to 35 mN / m or more.
[0085]
Next, the film subjected to the adhesion promoting treatment is set in a vacuum vapor deposition device provided with a film traveling device, and travels through a cooling metal drum. At this time, vapor deposition is performed by the evaporated metal vapor while heating and evaporating the aluminum metal. Alternatively, an oxygen gas is supplied to a portion where a metal vapor exists, and aluminum is oxidized to be agglomerated and deposited on a running film surface to form an aluminum oxide deposited layer and wound. By changing the ratio between the amount of aluminum evaporated and the amount of supplied oxygen gas at this time, the light transmittance of the aluminum oxide deposited film can be changed. After the evaporation, the inside of the vacuum evaporation apparatus is returned to normal pressure, and the wound film is slit. Thereafter, it is preferable to leave the battery at a temperature of 30 ° C. or more for one day or more for aging because the gas barrier property is stabilized.
[0086]
【Example】
Next, the effects of the present invention will be described with reference to examples, but the present invention is not limited to these examples. First, a method for measuring and evaluating a characteristic value will be described below.
[0087]
[Method of measuring and evaluating characteristic values]
The particle characteristics and film characteristic values of the present invention are measured by the following measurement methods.
(A) Particle characteristics
(1) Measurement of particle diameter ratio, average particle diameter, particle size distribution and calculation of relative standard deviation σ
The particles were mixed with polyester, cut into ultrathin sections having a thickness of 0.2 μm, and observed and measured for at least 100 particles with a transmission electron microscope. The formulas for calculating the relative standard deviation σ and the average particle diameter are as follows.
[0088]
(Equation 2)

[0089]
Here, σ represents the relative standard deviation, D represents the number average particle diameter (μm), Di represents the particle diameter (μm), and n represents the number of particles (pieces).
(2) Specific surface area of particles
The measurement was carried out by a method of determining the specific surface area of the solid from the amount of adsorption of the inert gas (BET method).
[0090]
(3) Silicon atom / aluminum atom molar ratio
The measurement was performed by X-ray fluorescence analysis.
[0091]
(4) Thermal decomposition temperature of particles
A thermogravimetric weight loss curve was measured at a heating rate of 20 ° C./min under a nitrogen atmosphere with Rigaku Denki TAS-100, and the 10% weight loss temperature was defined as the thermal decomposition temperature.
(B) Film characteristics
(1) Glass transition temperature (Tg)
Using a thermal analyzer DSCII type manufactured by Seiko Instrument Co., Ltd., 5 mg of a sample was held at 300 ° C. for 5 minutes, quenched with liquid nitrogen, and then the center of the transition point when the temperature was increased at a rate of 20 ° C./min. The temperature was measured and taken as the glass transition temperature (Tg).
[0092]
(2) Melting point (Tm)
Using a thermal analyzer DSCII type manufactured by Seiko Instrument Co., Ltd., the peak temperature of an endothermic melting curve when 5 mg of a sample was heated from room temperature at a heating rate of 20 ° C./min was measured, and the melting point (Tm ).
[0093]
(3) Intrinsic viscosity
The polyester was dissolved in orthochlorophenol and measured at 25 ° C.
[0094]
(4) Plane orientation coefficient fn
Using an Abbe refractometer manufactured by Atago Co., Ltd., the refractive index of the film was measured using a sodium lamp as a light source. The refractive index nγ in the longitudinal direction in the film plane, the refractive index nβ in the horizontal direction perpendicular to it, and the refractive index nα in the thickness direction are obtained, and the following formula is obtained.
fn = (nγ + nβ) / nα
To determine the plane orientation coefficient fn.
[0095]
(5) Average particle size
The following method can be used to determine the particle size of the particles contained in the film.
[0096]
The resin is removed from the film by a plasma low temperature ashing process to expose the particles. The processing conditions are selected so that the resin is ashed but the particles are not damaged. This was observed for 5,000 to 10,000 particles using a scanning microscope, and the average particle diameter was determined from the equivalent circle diameter of the particle image using an image processing device.
[0097]
When the particles are internal particles, a cross section of the polymer is cut to prepare an ultrathin section having a thickness of about 0.1 to 1 μm, and a photograph is taken with a transmission electron microscope at a magnification of about 5,000 to 20,000 (10). Sheets: 25 cm × 25 cm), and the average dispersion diameter of the internal particles was calculated from the equivalent circle diameter.
[0098]
(6) Center line average roughness (Ra)
The surface roughness was measured using a high-precision thin film step measuring device ET-10 manufactured by Kosaka Laboratory. The conditions were as follows, and the average value of the 20 measurements was taken as the center line average roughness (Ra).
・ Stylus tip radius: 0.5 μm
・ Stylus load: 5mg
・ Measurement length: 1mm
・ Cut off: 0.08mm
The definition of Ra is shown, for example, in Chapter 5, Surface Roughness Measurement Method P134 ~ by "Surface Measurement Techniques and Their Applications" by Suehisa Kawamura and Yoshikazu Nakamura (Kyoritsu Shuppan Co., Ltd.).
[0099]
(7) Heat shrinkage
A surface line was drawn on the surface of the film sample at a mark line distance of 200 mm, and the film sample was cut at a film width of 10 mm. This sample was hung in the length direction, a load of 1 g was applied in the length direction, and heated for 30 minutes using hot air at 150 ° C. Then, the length between the marked lines was measured, and the shrinkage of the film was measured as the original size. % (Percentage (%)). In addition, when the film was elongated, it was indicated by a minus (-) value.
[0100]
(8) Optical density (OD)
In accordance with JIS-K-7605, the transmission density of the vapor-deposited film when the filter was set to Visual was measured using a transmission densitometer TR927 manufactured by Macbeth Co., Ltd., and the optical density was determined.
[0101]
(9) Light transmittance
The transmittance of the deposited film at a wavelength of 550 nm was determined using a spectrophotometer 324 manufactured by Hitachi, Ltd.
[0102]
(10) Gas barrier properties
A. Water vapor transmission rate (moisture proof)
The value measured using a water vapor permeability meter “PERMATRAN” W3 / 31 manufactured by Modern Control Company under the conditions of a temperature of 37.8 ° C. and a relative humidity of 100% is shown in units of g / m 2 · day.
[0103]
B. Oxygen permeability
Using an oxygen permeability meter “OXTRAN” -100 manufactured by Modern Control Co., the value measured under the conditions of a temperature of 23 ° C. and a relative humidity of 80% was shown in units of ml / m 2 · day · MPa.
[0104]
(11) Film thickness composition and inorganic thin film layer thickness
A cross section of the film was photographed with a transmission electron microscope (TEM) under the following conditions, and the thickness configuration of the film and the thickness of the inorganic thin film layer were measured.

(12) Adhesion of deposited film
A non-stretched propylene film (CPP) (T3931 manufactured by Toray Synthetic Film Co., Ltd., 60 μm) was adhered to the vapor-deposited surface of the vapor-deposited film using a polyurethane-based adhesive. Then, 180 ° peeling of the CPP and the vapor-deposited inorganic thin film was performed at a peeling rate of 100 mm / min using “Tensilon”. The peel strength in dry condition (25 ° C., 50% RH atmosphere) was measured. When the peeling strength was 2 N / cm or more, the adhesion was evaluated as ○, when the peeling strength was less than 1 N / cm, and when the intermediate value was ／.
[0105]
(13) Handling properties
Regarding the handleability (slipperiness, etc.) of the film at the time of vapor deposition and processing, る も の indicates that the handleability was excellent, △ indicates that the handleability was poor but there was no practical problem, and X indicates that the handleability was poor.
[0106]
Next, the method for producing a film of the present invention will be described with reference to an example in which the film is laminated in the order of film / surface treatment / inorganic thin film, but it goes without saying that the present invention is not limited to this example.
[0107]
【Example】
The following aluminum silicate particles, particle master, and polyester were used in Examples and Comparative Examples.
(Aluminum silicate particles A) A 3.5% by weight solution of sodium silicate was desalted through an H-type ion exchange resin column, and a 1.5% by weight solution of sodium hydroxide was added thereto to adjust the pH to 9. 20% by weight of the obtained mixed solution is collected, heated at 100 ° C. for 10 minutes, then cooled to 90 ° C., and the remaining mixed solution is added little by little with stirring until the particle diameter becomes 0.30 μm. The seed particles of silica were obtained by growing the particles.
[0108]
Then, a 5% by weight slurry of the seed particles was adjusted to pH = 12.5 with sodium hydroxide, and a 0.5% by weight solution of sodium aluminate and a 1.5% by weight solution of water glass were simultaneously added thereto. Then, a part of the solution was separated, heated at 100 ° C. with stirring, cooled to 90 ° C., and kept at 90 ° C. The remaining aqueous solution was added at an addition speed of 100 g / min and stirred at a stirring speed of 50 rpm to give a volume average particle size of 0.1. After diluting the particle-containing aqueous solution obtained by growing it to 53 μm with 100 times pure water, it is spray-dried at a temperature of 150 to 250 ° C. to thereby form aluminum silicate particles A (volume average particle diameter: 0). .53 μm, particle diameter ratio: 1.02, specific surface area: 8.7 m ² / G, silicon / aluminum ratio: 3.2, relative standard deviation: 0.09, refractive index: 1.482). The mixing ratio is 5% by weight of seed particles / 0.5% by weight of sodium aluminate solution / 1.5% by weight of water glass solution = 2.5% by weight / 30.9% by weight / 20.2% by weight.
(Aluminum silicate particles B) The particles were grown until the particle diameter of the seed particles became 0.10 μm, and the mixing ratio of the aqueous solution (5% by weight of seed particles / 0.5% by weight of sodium aluminate solution / water glass 1) Aluminum silicate particles B (volume average particle diameter: volume average particle diameter: 0.55% by weight = 0.25% by weight / 19.7% by weight / 13.0% by weight) except for changing the solution. 0.31 μm, particle diameter ratio: 1.04, specific surface area: 15.2 m ² / G, silicon / aluminum ratio: 2.3, relative standard deviation: 0.10, refractive index: 1.521).
(Aluminum silicate particles C) Particles were grown until the particle diameter of the seed particles became 0.13 μm, and the mixing ratio of the aqueous solution (5% by weight of seed particles / 0.5% by weight of sodium aluminate solution / water glass 1) Aluminum silicate particles C (volume average particle diameter: 2.5 wt% solution = 2.5 wt% / 35.4 wt% / 11.1 wt%) in the same manner as aluminum silicate A, except that 0.20 μm, particle diameter ratio: 1.01, specific surface area: 23.1 m ² / G, silicon / aluminum ratio: 2.1, relative standard deviation: 0.13, refractive index: 1.512).
(Particle master A) 10% by weight of the above-mentioned aluminum silicate particles A and 90% by weight of ethylene glycol were mixed and stirred at room temperature for 2 hours with a dissolver to obtain an ethylene glycol slurry (A) of aluminum silicate particles.
[0109]
Next, after 100% by weight of dimethyl terephthalate and 44% by weight of elethin glycol were added with magnesium acetate as a catalyst to carry out a transesterification reaction, 0.5% of the previously prepared slurry (A) was added to the reaction product. , An antimony trioxide as a catalyst and trimethyl phosphate as a heat stabilizer were added to carry out a polycondensation reaction to obtain polyethylene terephthalate containing 1% by weight of aluminum silicate particles.
(Particle master B) A polyethylene terephthalate resin containing 1% by weight of aluminum silicate particles was obtained in the same manner as the particle master A using the above-mentioned aluminum silicate particles B.
(Particle master C) A polyethylene terephthalate resin containing 1% by weight of aluminum silicate particles was obtained in the same manner as the particle master A using the above-mentioned aluminum silicate particles C.
(Particle Master D) Using agglomerated silica particles (volume average particle diameter: 1.4 μm, refractive index: 1.618), a polyethylene terephthalate resin containing 2% by weight of agglomerated silica particles was obtained in the same manner as Particle Master A. .
(Particle Master E) Using colloidal silica particles (volume average particle diameter: 0.35 μm, refractive index: 1.623), a polyethylene terephthalate resin containing 1% by weight of colloidal silica particles was obtained in the same manner as in Particle Master A. .
(Polyethylene terephthalate A (PET-A)) A mixture of 100% by weight of dimethyl terephthalate and 60% by weight of ethylene glycol was mixed with 0.09% by weight of magnesium acetate and 0.03% by weight of antimony trioxide based on the amount of dimethyl terephthalate. After the addition, the ester exchange reaction was carried out by heating and raising the temperature by a conventional method. Next, 0.020% by weight of an aqueous 85% phosphoric acid solution based on the amount of dimethyl terephthalate is added to the transesterification reaction product, and the mixture is transferred to a polycondensation reaction layer. Next, the reaction system was gradually depressurized while heating and heated, and a polycondensation reaction was carried out at 290 ° C. under a reduced pressure of 1 mmHg by a conventional method to obtain a polyethylene terephthalate resin (melting point 256 ° C., intrinsic viscosity 0.64).
(Polyethylene naphthalate A (PEN-A)) A polyethylene naphthalate resin (melting point: 270 ° C.) was prepared in the same manner as in PET-A, except that dimethyl 2,6-naphthalenedicarboxylate was changed to 100% by weight instead of dimethyl terephthalate. And an intrinsic viscosity of 0.69 dl / g).
(Polybutylene terephthalate A (PBT-A)) Polyethylene terephthalate (melting point: 228 ° C., intrinsic viscosity: 1.26 dl / g) manufactured by Toray under the trademark “Trecon” 1200S was used.
(Polyetherester A (PEE-A)) A polyetherester of “Hytrel” 3078 (trade name, manufactured by Dupont Toray Co., Ltd., melting point 170 ° C., melt flow index (MI) 5.0 g / min) was used.
(Polyetherester B (PEE-B)) A polyetherester of “Hytrel” 7277 manufactured by Toray DuPont (melting point: 219 ° C, melt flow index (MI): 1.5 g / min) was used.
[0110]
Table 1 shows the composition of the resin prepared as described above. After appropriately drying these resins, blending was performed at the mixing ratios shown in Table 1, and film formation was performed through melt extrusion, stretching, and heat treatment steps to obtain a film having a thickness of 12 μm.
[0111]
(Example 1)
As a raw material of the base film A of the film of the present invention, PET-A / particle master D = a mixed resin having a weight ratio of 97.5 / 2.5 was used, and as a polyester B, PET-A / particle master A = A mixed resin having a weight ratio of 99.5 / 0.5 was used. After sufficiently drying each pellet under vacuum, it is supplied to a separate extruder and melted at 280 ° C., and after obtaining each filtration filter, it is led to a slit-shaped two-layer die, and a base film A layer / polyester The layers were laminated in the order of layer B, which was wound around a cooling drum having a surface temperature of 25 ° C. to be cooled and solidified. In order to improve the adhesion between the sheet and the surface of the cooling drum during this time, a wire electrode was arranged on the sheet side and a DC voltage of 6 kV was applied. The unstretched film thus obtained was heated to 90 ° C. and stretched 3.1 times in the longitudinal direction to obtain a uniaxially stretched film. The film is gripped by a clip, guided into a tenter, stretched 4.0 times in the width direction at 95 ° C., and further subjected to a heat treatment for 5 seconds in an atmosphere of 238 ° C. to form a 12 μm-thick packaging film (base film A). / Laminate thickness of polyester B = 11/1 μm).
[0112]
Next, the obtained packaging film was passed through a rubber roll heated to 50 ° C., and the polyester B laminated surface was heated to 40 W · min in an atmosphere of a mixed gas of nitrogen / carbon dioxide (nitrogen / carbon dioxide = 85/15). / M ² The film was subjected to a corona discharge treatment under the above conditions, and the film was wound into a roll with the wet tension of the film being 45 mN / m or more. The temperature of the film at that time was 30 ° C., and the film was allowed to stand for 10 hours and slit into a small width. Next, the film slit to a small width was set in a vacuum evaporation apparatus equipped with a film traveling device, and the film was cut into a 1.00 × 10 5 ^-2 After a high vacuum of Pa, the sample was run through a cooling metal drum at -20 ° C. At this time, while heating and evaporating the aluminum metal, the aluminum film was agglomerated and deposited on the corona discharge treated surface of the running film to form a deposited aluminum thin film layer and wound it. After the evaporation, the inside of the vacuum evaporation apparatus was returned to normal pressure, the wound film was rewound, and aged at a temperature of 40 ° C. for 2 days to obtain an evaporation film. The thickness of the inorganic thin film of this vapor deposition film was 45 nm.
[0113]
(Example 2)
As a raw material of the base film A of the film of the present invention, a mixed resin having a PEN-A / particle master D = weight ratio of 97.5 / 2.5 was used, and as a polyester B, PET-A / PBT-A / Particle Master A = Using a mixed resin having a weight ratio of 94.0 / 5.0 / 1.0, sufficiently vacuum-drying each pellet, and then feeding them to separate extruders to melt them at 290 ° C. After each filtration filter was obtained, it was led to a slit-shaped two-layer die, laminated in the order of substrate film A / polyester B, wound around a cooling drum having a surface temperature of 25 ° C., and cooled and solidified. In order to improve the adhesion between the sheet and the surface of the cooling drum during this time, a wire electrode was arranged on the sheet side and a DC voltage of 6 kV was applied. The unstretched film thus obtained was heated to 135 ° C. and stretched 3.1 times in the longitudinal direction to obtain a uniaxially stretched film. The film is gripped with a clip, guided into a tenter heated to 100 ° C., continuously stretched 4.0 times in the width direction in a region heated to 140 ° C., and further heated at 238 ° C. for 5 seconds. Heat treatment was performed to obtain a packaging film having a film thickness of 12 μm (laminated thickness of base film A / polyester B = 11.9 / 0.1 μm). The packaging film was evaporated in the same manner as in Example 1 to obtain an inorganic thin film having a thickness of 45 nm.
[0114]
(Example 3)
As a raw material of the base film A of the film of the present invention, PET-A / PBT-A / PEE-A / particle master D = mixing in a weight ratio of 77.5 / 19.0 / 1.0 / 2.5. A resin was used, and a mixed resin having a weight ratio of PET-A / particle master B = 95.0 / 5.0 was used as a raw material of the polyester B. The mixed pellets of the base film A, PET is 180 ° C. × 4 hours, PBT is 150 ° C. × 4 hours, PEE is 70 ° C. × 24 hours, sufficiently vacuum-dried, and PET and PBT are cooled down to 70 ° C. A raw film having a film thickness of 12 μm (laminated film composed of a base film A layer / polyester B layer = 10 μm / 2 μm) was obtained in the same manner as in Example 1 except that PEE was mixed and used. Was. Using the raw film, a vapor-deposited film of the present invention having a thickness of 45 nm of an inorganic thin film was obtained in the same manner as in Example 1.
[0115]
(Example 4)
As a raw material of the base film A of the film of the present invention, PET-A / PBT-A / PEE-B / particle master D = mixing in a weight ratio of 72.5 / 20.0 / 5.0 / 2.5. As a raw material of the polyester B, a mixed resin having a weight ratio of PET-A / particle master C = 80.0 / 20.0 was used. The raw material of the base film A was mixed in the same manner as in Example 3, and the raw film having a film thickness of 12 μm (laminated thickness of the base film A layer / polyester B layer = 11 μm) was obtained in the same manner as in Example 1. / 1 µm). Further, a vapor deposition film of the present invention having a thickness of 45 nm of the inorganic thin film was obtained in the same manner as in Example 1.
[0116]
(Example 5)
As a raw material of the base film A of the film of the present invention, a mixed resin having a ratio of PET-A / particle master D = weight ratio of 97.5 / 2.5 was used. As a polyester B, PET-A / PBT-A / Particle Master A = A mixed resin having a weight ratio of 77.0 / 20.0 / 3.0 was used. In the same manner as in Example 1, an original film having a film thickness of 12 μm (laminated film composed of the base film A layer / polyester B layer = 7 μm / 5 μm) was obtained. Further, a packaging film of the present invention having a thickness of 45 nm of the inorganic thin film was obtained in the same manner as in Example 1.
[0117]
Table 1 summarizes the quality evaluation results of the above packaging films for vapor deposition. As can be seen from the results in Table 1, the deposited films obtained in Examples 1 to 4 were excellent in gas barrier properties, handling properties, and deposition adhesion.
[0118]
(Comparative Example 1)
The composition of the polyester B was a PET-A / particle master D = weight ratio 95.5 / 0.5 using a mixed resin at a ratio of 95.5 / 0.5. Layer / polyester B layer thickness = 6 μm / 6 μm). Further, a vapor deposition film having a thickness of 45 nm of an inorganic thin film was obtained in the same manner as in Example 1.
[0119]
(Comparative Example 2)
The composition of the polyester B was a PET-A / particle master A = a mixed resin having a weight ratio of 20.0 / 80.0, and a 12 μm-thick raw film (base film A) was produced in the same manner as in Example 1. Layer / polyester B layer laminated thickness = 11 μm / 1 μm). Further, a vapor deposition film having a thickness of 45 nm of an inorganic thin film was obtained in the same manner as in Example 1.
[0120]
(Comparative Example 3)
A mixed resin in which the composition of polyester B was mixed at a ratio of PET-A / PBT-A / particle master E = 20.0 / 20.0 / 60.0 by weight was used. In the same manner as in Example 1, an original film having a film thickness of 12 μm (laminated film composed of base film A layer / polyester B layer = 11 μm / 1 μm) was obtained. Further, a vapor deposition film having a thickness of 45 nm of an inorganic thin film was obtained in the same manner as in Example 1. The vapor-deposited films obtained in Comparative Examples 1 to 3 had poor gas barrier properties, and all of the vapor-deposited films were not preferable as packaging films.
[0121]
[Table 1]

[0122]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, the packaging film and vapor deposition film which were excellent in vapor deposition processability and gas barrier property can be stably provided.

Claims (6)

A packaging film in which a polyester B layer containing 0.005 to 0.5% by weight of aluminum silicate particles is laminated on at least one side of a polyester film A to a thickness of 0.01 to 5 μm. The packaging film according to claim 1, wherein the polyester film A is polymerized from a dicarboxylic acid component containing terephthalic acid and / or 2,6-naphthalenedicarboxylic acid as a main component and a glycol component containing ethylene glycol as a main component. . The packaging film according to any one of claims 1 to 2, wherein the polyester B layer is a polyester comprising 95 to 60% by weight of an ethylene terephthalate component and 5 to 40% by weight of a butylene terephthalate component. The center line average surface roughness (Ra) of the surface of the polyester B layer is in the range of 0.005 to 0.030 μm, and the heat shrinkage when heated at 150 ° C. for 30 minutes is 0 in the longitudinal direction of the film. The packaging film according to any one of claims 1 to 3, wherein the thickness is in the range of 0.5 to 2% and in the width direction of -1.2 to 0.5%. A vapor-deposited film comprising an inorganic film formed by vapor deposition on the surface of the packaging film according to any one of claims 1 to 4 on the polyester B layer side. The vapor-deposited film according to claim 5, wherein the inorganic film is an aluminum film and / or a metal oxide film.