JP4104383B2 - Transparent water vapor barrier film and method for producing the same - Google Patents

Description

（３）前記有機物層の厚みが、０．０１μｍ以上５μｍ以下であることを特徴とする（１）又は（２）の透明水蒸気バリアフィルム、
（４）前記有機物層が真空蒸着によって製膜されてなることを特徴とする（１）〜（３）の透明水蒸気バリアフィルム、
（５）前記有機物層がＵＶによって架橋されてなるを特徴とする（１）〜（４）の透明水蒸気バリアフィルム、
（６）前記無機物層が珪素酸化物または珪素窒化物または珪素窒化酸化物を主成分とする（１）〜（５）の透明水蒸気バリアフィルム、
（７）前記樹脂基材のガラス転移温度が２００℃以上である（１）〜（６）の透明水蒸気バリアフィルム、
（８）前記樹脂基材がポリエーテルスルホンまたはノルボルネン系樹脂を主成分とする（１）〜（７）の透明水蒸気バリアフィルム、
（９）樹脂基材上に少なくとも、無機物層／有機物層／無機物層からなるバリア膜を形成後に加熱処理をすることを特徴とする（１）〜（８）の透明水蒸気バリアフィルムの製造方法、
である。
【０００７】
【発明の実施の形態】
以下、本発明を詳細に説明する。
本発明では、樹脂基材上に、少なくとも無機物層／有機物層／無機物層で構成されたバリア膜を形成することで、無機物の単一層だけでは達成困難な高い水蒸気バリア性を実現することができる。特に、無機物層と無機物層との間に有機物層を介在させることによって、無機物の単一層だけでは無くしきれない層構造の欠陥部分を有機物層が埋めて平滑化し、欠陥点の少ない第２の無機物層が形成され高い水蒸気バリア性が得られるものと考えられる。また、有機物層を介在させることにより、曲げに対するバリア性の劣化を抑制される。
本発明で用いる有機物層は、アクリロイル基以外に少なくとも１つ以上の極性基を有するジアクリレートを架橋させてなる樹脂を主成分とするものであれば、特に限定されない。極性基を有するジアクリレートを架橋させてなる樹脂は、無機物層との密着性に優れ、かつ耐薬品性に優れるため、この有機物層を用いた水蒸気バリア性フィルムは、有機ＥＬディスプレイや液晶ディスプレイの製造プロセスでの薬品処理工程や洗浄工程を通してもその優れた水蒸気バリア性を維持することができる。
本発明で用いるジアクリレートが有する極性基としては、無機物層との密着性を向上させるものであれば特に制限されないが、例としては、エーテル結合、エステル結合、ウレタン結合、アミド結合、水酸基、などがあげられ、透明性や熱安定性の面からエーテル結合やエステル結合が好ましく、エーテル結合がより好ましい。
【０００８】
エーテル結合やエステル結合を有するジアクリレートの好ましい例としては、ネオペンチルグリコール変性トリメチロールプロパンジアクリレート、エピクロロヒドリン変性１，６−ヘキサンジオールジアクリレート、ポリプロピ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アクリレート、トリグリセロールジアクリレート、カプロラクトン変性ヒドロキシピバリン酸ネオペンチルグリコールジアクリレート、ヒドロキシピバリン酸ネオペンチルグリコールジアクリレート、ビス（アクリロキシネオペンチルグリコール）アジペート等が挙げられる。これらの中でも、耐熱性が優れた一般式（１）で示されるネオペンチルグリコール変性トリメチロールプロパンジアクリレートなどの環状エーテル構造を有するジアクリレートが最も好ましい。
【化３】

これらのジアクリレートは単独で用いても、２種類以上を混合しても良く、これらのジアクリレートが主成分であれば１官能や３官能以上のアクリレートや他の反応性モノマーおよび／またはオリゴマーを併用して用いてもかまわない。
【０００９】
有機物層の厚みは０．０１〜５μｍが好ましく、より好ましくは０．０５〜３μｍであり、最も好ましくは０．１〜２μｍである。有機物層の厚みが０．０１μｍよりも小さいと欠陥部分を埋めきれずバリア性が低下するおそれがある。一方、有機物層の厚みが５μｍよりも大きいと端面からの吸水によってバリア性が低下するおそれがある。
有機物層を形成する方法は特に制限されず、真空蒸着などのドライプロセスやディップコート、バーコート、スピンコートなどのウェットプロセスが適用できる。特に無機物層を真空下で形成する場合は、真空蒸着で成膜することが好ましい。有機物層を真空蒸着で製膜すれば、真空下で連続的に無機物層、有機物層、無機物層を積層できるためコスト的に有利となる。
【００１０】
有機物層を成膜する方法として真空蒸着を用いる場合には有機物層に用いるジアクリレートには適度な揮発性を有することが好ましく、揮発性から考慮すると有機物層に用いるジアクリレートの分子量は２００〜１０００であることが好ましい。より好ましくは２５０〜８００であり、さらに好ましくは３００〜７００であり、最も好ましくは３００〜６００である。分子量が２００より低い場合、基材温度が上昇すると蒸着効率が低下するおそれがある。一方、分子量が１０００を超えると揮発性が低いために蒸着困難となり、場合によっては蒸発する前に硬化するおそれがある。
【００１１】
有機物層に用いるジアクリレートを架橋する方法としては特に制限はないが、設備が安価であることと、硬化が速いことからＵＶを用いて架橋することが好ましい。この場合、光重合開始剤を添加してもいるのが好ましい。
用いる光重合開始剤は、特に限定されないが、ジアクリレートを主成分とする樹脂を真空蒸着で製膜する場合は、ジアクリレートと揮発性が類似していることが好ましい。
光重合開始剤の例としては、１−ヒドロキシシクロヘキシルフェニルケトン、２，２−ジメトキシ−１，２−ジフェニルエタン−１−オン、２−メチル−１[４−（メチルチオ）フェニル]−２−モリフォリノプロパン−１−オン、２−ヒドロキシ−２−メチル−１−フェニルプロパン−１−オン、１−[４−（２−ヒドロキシエトキシ）−フェニル]−２−ヒドロキシ−２−メチル−１−プロパン−１−オン、ビス（２，４，６−トリメチルベンゾイル）−フェニルフォスフィンオキサイド等が挙げられる。これら光重合開始剤は単独で用いても２種以上併用してもかまわない。
【００１２】
光重合開始剤の添加量はジアクリレートを主成分とする樹脂１００重量部に対し０．１〜１０重量部が好ましい。より好ましくは０．５〜７重量部であり、最も好ましくは０．８〜５重量部である。光重合開始剤の含有量が０．１重量部より少なくなると硬化が不十分となるおそれがある。一方、光重合開始剤の含有量が１０重量部を超えると硬化は起こるものの脆い有機層となるおそれがある。
【００１３】
本発明の無機物層は、透明で水蒸気バリア性を有するものであれば特に制限されず、例えばSi、Al、In、Sn、Zn、Ti、Cu、Ce等の１種以上を含む酸化物もしくは窒化物もしくは酸化窒化物などを用いることができる。中でも水蒸気バリア性と高透明性を両立させるには無機物層として珪素酸化物や珪素酸化窒化物を使うのが好ましい。珪素酸化物はSiOxと表記され、たとえば、無機物層としてSiOxを用いる場合、良好な水蒸気バリア性と高い光線透過率を両立させるためには1.6<ｘ<1.9であることが望ましい。珪素酸化窒化物はSiOxNyと表記されるが、このxとyの比率は密着性向上を重視する場合、酸素リッチの膜とし、1<x<2、0<y<1が好ましく、水蒸気バリア性向上を重視する場合、窒素リッチの膜とし、0<x<0.8、0.8<y<1.3が好ましい。２層ある無機物層は、それぞれ同じ組成でも別の組成でも良い。
無機物層の厚みは、特に限定されないが、５ｎｍ〜５００ｎｍが好ましい。厚みが５００ｎｍ以上では曲げ応力によるクラックの恐れがあり、５ｎｍ以下では膜が島状に分布する場合があり、いずれも水蒸気バリア性が悪くなる恐れがある。
無機物層の形成方法としては抵抗加熱蒸着法、電子線蒸着法、イオンプレーティング法、ＣＶＤ法、スパッタリング法が適用でき、目的の無機酸化物、無機窒化物、無機窒化酸化物が得られる方法であれば制限はない。
【００１４】
本発明の樹脂基材は特に限定されないが、例としては、ポリスルホン、ポリエーテルスルホン、ノルボルネン樹脂、ポリカーボネート、ポリアリレート、ポリアクリレート、ポリエステル、ポリアミド、エポキシ樹脂、ポリイミド、ポリオレフィン等を使用することができる。特に、ガラス転移温度が２００℃以上のノルボルネン系樹脂やポリエーテルスルホンは光学特性が良好で耐熱性が高く、有機物層無機物層形成プロセスにおいて高温処理による変形や劣化が無いので好ましい。
【００１５】
本発明においては、樹脂基材と無機物層との密着性を向上させる目的で、樹脂基材と無機物層との間にも有機物層を設けることができる。この場合の有機物層は、樹脂基材と無機物層との密着性を向上させるものであれば特に限定されないが、好ましい例としては、エポキシアクリレート、ウレタンアクリレート、イソシアヌル酸アクリレート、ペンタエリスリトールアクリレート、トリメチロールプロパンアクリレート、エチレングリコールアクリレート、ポリエステルアクリレートなどが挙げられる。これらのうち、特にイソシアヌル酸アクリレート等のように架橋度が高く、ガラス転移温度が１８０℃以上であることが好ましい。また、単独で用いても、２種類以上を混合してもかまわない。さらに、それ自体で比較的バリア性のあるＰＶＡ系やＥＶＡ系、ポリ塩化ビニリデン、もしくはこれらの樹脂の複数を混用することもできる。樹脂基材直上の有機物層については、その厚みの制限は特に無いが、０．０１〜１０μｍが好ましい。
【００１６】
本発明透明水蒸気バリアフィルムは、樹脂基板上に、少なくとも無機物層／有機物層／無機物層からなるバリア膜層を形成した後に、加熱処理することが好ましい。加熱処理をすることによって、無機物層と有機物層との密着性が向上する。加熱処理温度は、用いる基材と有機物層によって好ましい温度が異なるが、例えば基材にポリエーテルスルホンを用い、有機物層に環状エーテル構造を有するネオペンチルグリコール変成トリメチロールプロパンジアクリレートを用いた場合には、１００〜２００℃が好ましく、より好ましくは１２０〜２００℃である。
【００１７】
【実施例】
以下本発明の実施例について詳細に説明するが、本発明は、何ら下記実施例に限定されるものではない。
（実施例１）
ポリエーテルスルホンフィルムにイソシアヌル酸トリアクリレート（東亜合成：アロニックスＭ−３１５）25wt%、ジエチレングリコール50wt%、酢酸エチル24wt%、シランカップリング剤１wt%からなる均一な混合溶液をスピンコーターで塗布し、80℃10分加熱乾燥後さらにＵＶ照射で硬化させて２μｍの樹脂層を形成した。つぎに、抵抗加熱端子及び電子銃を備えた真空蒸着機内に高圧水銀ＵＶランプを取り付けた成膜装置の真空槽内に前記有機物層を形成したフィルムをセットし１０^−４Ｐａ台まで真空引きした後に、電子線蒸着法により３０ｎｍの珪素窒化酸化物膜を形成した。その後、真空槽内の真空度が１０^−４Ｐａ台で安定した状態で、有機蒸着源の抵抗加熱を開始し、不純物の蒸発が完了したところで蒸着シャッターを開き５００ｎｍの有機層を蒸着した。蒸着した有機層の組成は、環状エーテル構造を有するジアクリレートであるネオペンチルグリコール変性トリメチロールプロパンジアクリレート（ＫＡＹＡＲＡＤ Ｒ−６０４：日本化薬（株）製）１００重量部に光重合開始剤（イルガキュア−６５１：チバ・スペシャルティ・ケミカルズ製）を１重量部添加したものを用いた。蒸着シャッターを戻した後にＵＶランプのシャッターを開き、５００ｍＪ／ｃｍ^２の積算光量で硬化した。その後さらに電子線蒸着法による３０ｎｍの珪素窒化酸化物膜形成を繰り返し、樹脂基板／有機物層▲１▼／無機物層▲１▼／有機物層▲２▼／無機物層▲２▼の透明水蒸気バリアフィルムを形成した。形成された前記透明水蒸気バリアフィルムに真空下のまま加熱処理（１３０℃×１ｈ＋２００℃×３ｈ）を実施し、その後評価を行った。
【００１８】
（比較例１）
無機物層▲１▼と無機物層▲２▼に挟まれた有機物層▲２▼の形成を行わない以外は実施例１と同様に、ポリエーテルスルホンフィルム上に有機物層▲１▼/無機物層▲１▼/無機物層▲２▼の形成を行った。
【００１９】
（比較例２）
実施例１で使用したネオペンチルグリコール変性トリメチロールプロパンジアクリレート（ＫＡＹＡＲＡＤ Ｒ−６０４：日本化薬（株）製）の代わりに、アクリロイル基以外に極性基を持たないジシクロペンタジエニルジアクリレート（アロニックスM-２０３：東亞合成（株）製）を用いた他は実施例１と同様に、ポリエーテルスルホンフィルム上に有機物層▲１▼/無機物層▲１▼/有機物層▲２▼/無機物層▲２▼の形成を行った。
【００２０】
（評価）
各フィルムの水蒸気透過度をJISK7129B法にて測定した。また、30mmφの棒に１回巻きつけた後、再度水蒸気透過度をJISK7129B法にて測定した。さらに、６０℃９５％ＲＨの恒温恒湿槽にフィルムを２４ｈ入れた後、再度水蒸気透過度をJISK7129B法にて測定した。結果を表１に示す。
【００２１】
【表１】

【００２２】
実施例１においては、いずれの評価結果も表示素子用としての要求特性を十分に満たしていたが、有機物層▲２▼を形成しない比較例１では、無機物層を２層重ねており厚みが大きくなる分、曲げに弱くクラックが入りやすいため実施例に比較して水蒸気透過度が増大したと考えられる。また、有機物層▲２▼が極性を持たないジアクリレートで形成された比較例２では、有機物層と無機物層の密着性が低いため、加熱加湿処理（６０℃・９５％ＲＨ×２４ｈ）により有機物層と無機物層の界面で剥離が生じ、水蒸気透過度が増大したと考えられる。
【００２３】
【発明の効果】
本発明は、高い水蒸気バリアをもつ透明フィルムであり、しかも加熱加湿処理及び曲げを施しても水蒸気バリア性が低下しないという特性を持つものである。本発明のフィルムをたとえば表示用素子として適用すれば、軽くて割れないディスプレイが実現できる。また、薬品などの保存に適用すれば中身が見えて、落としても割れないような保存容器を実現することも可能であり、その工業的価値は極めて高い。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a transparent film having a high water vapor barrier property that can be applied to a wide range of uses such as optical members, electronics members, general packaging members, and medicine packaging members.
[0002]
Conventionally, a gas barrier film in which a metal oxide thin film such as aluminum oxide, magnesium oxide, silicon oxide or the like is formed on the surface of a plastic substrate or film is used for packaging goods and foods that require blocking of various gases such as water vapor and oxygen. It is widely used in packaging applications to prevent the alteration of industrial products and pharmaceuticals. Moreover, it is used with a liquid crystal display element, a solar cell, an electroluminescence (EL) substrate, etc. besides the packaging use. In particular, transparent substrates, which have been applied to liquid crystal display elements and EL elements, have recently been required to be lighter and larger, and have long-term reliability and a high degree of freedom in shape, and curved display is possible. With the addition of high demands such as that, film substrates such as transparent plastics have begun to be used instead of glass substrates that are heavy, fragile and difficult to increase in area. In addition, the plastic film not only satisfies the above requirements, but also has a roll-to-roll method, and is therefore more advantageous than glass because of higher productivity and cost reduction.
[0003]
However, a film substrate such as a transparent plastic has a problem that the gas barrier property is inferior to glass. If a base material with inferior gas barrier properties is used, water vapor or air will permeate, causing deterioration of the liquid crystal in the liquid crystal cell, for example, resulting in display defects and deterioration of display quality. In order to solve such problems, it is known to form a metal oxide thin film on a film substrate to form a gas barrier film substrate. Gas barrier films used for packaging materials and liquid crystal display elements include those obtained by vapor-depositing silicon oxide on a plastic film (Japanese Patent Publication No. 53-12953) and those obtained by vapor-depositing aluminum oxide (Japanese Patent Laid-Open No. 58-217344). Are known, and each has a water vapor barrier property of about 1 g / m ² / day. In recent years, due to the development of large-sized liquid crystal displays, high-definition displays, etc., the demand for gas barrier performance on film substrates has increased to about 0.1 g / m ² / day for water vapor barriers. In order to meet this demand, film formation by sputtering or CVD has been studied as a means for expecting higher barrier performance.
[0004]
However, in recent years, organic EL displays and high-definition color liquid crystal displays that require further barrier properties have been developed, and while maintaining the transparency that can be used for them, even higher barrier properties, especially 0.1 g for water vapor barriers. Substrates with performance of less than / m ² / day have been required. In response to these requirements, WO 00/26973 proposes a technique for producing a barrier film having an alternating multilayered structure of organic layers / inorganic layers by a vacuum deposition method. Vacuum deposition of organic layers, which is a dry process, (1) High-purity organic thin films can be obtained because no solvent is used, (2) Thin films can be easily obtained, and film thickness controllability is good, (3) Foreign substances, etc. It has features such as contamination is difficult to enter. Further, if the organic layer can be formed under vacuum, the process of repeating normal pressure-vacuum required when alternately laminating the organic layer / inorganic layer can be omitted, and the productivity is improved. However, when a barrier film having a conventional multilayer structure of alternating organic / inorganic layers is applied to a film substrate for an organic EL display or a liquid crystal display, the organic treatment is performed by a chemical treatment process or a cleaning process in the manufacturing process. There was a possibility that separation between the layer and the inorganic layer occurred and the barrier property was lowered.
[0005]
[Problems to be solved by the invention]
An object of the present invention is to provide a transparent film that has a higher water vapor barrier performance than before and that does not deteriorate the barrier performance through the manufacturing process of an organic EL display or a liquid crystal display.
[0006]
[Means for Solving the Problems]
As a result of intensive studies to achieve the above-mentioned problems, the present inventors have found that a transparent water vapor barrier film having a barrier film composed of at least an inorganic layer / organic layer / inorganic layer on a resin substrate, the organic layer is acryloyl. A transparent water vapor barrier film mainly composed of a resin obtained by crosslinking a diacrylate having at least one polar group in addition to a group has a water vapor barrier performance higher than that of a conventional process, and a process for producing an organic EL display or a liquid crystal display Through this process, it was found that the barrier performance was not deteriorated, and the present invention was achieved.
That is, the present invention
(1) A transparent water vapor barrier film having a barrier film composed of at least an inorganic layer / organic layer / inorganic layer on a resin substrate, wherein the organic layer has at least one polar group other than an acryloyl group A transparent water vapor barrier film mainly composed of a crosslinked resin , wherein the diacrylate is a diacrylate having a cyclic ether structure ,
( 2 ) The transparent water vapor barrier film of (1), wherein the acrylate having the cyclic ether structure is a diacrylate represented by the general formula (1),
[Chemical formula 2]

( 3 ) The transparent water vapor barrier film of (1) or (2) , wherein the organic layer has a thickness of 0.01 μm or more and 5 μm or less,
( 4 ) The transparent water vapor barrier film of (1) to ( 3 ), wherein the organic layer is formed by vacuum deposition,
( 5 ) The transparent water vapor barrier film of (1) to ( 4 ), wherein the organic layer is crosslinked by UV,
( 6 ) The transparent water vapor barrier film of (1) to ( 5 ), wherein the inorganic layer contains silicon oxide, silicon nitride, or silicon nitride oxide as a main component,
( 7 ) The transparent water vapor barrier film of (1) to ( 6 ), wherein the glass transition temperature of the resin substrate is 200 ° C. or higher,
( 8 ) The transparent water vapor barrier film according to any one of (1) to ( 7 ), wherein the resin base material contains polyethersulfone or norbornene-based resin as a main component,
( 9 ) The method for producing a transparent water vapor barrier film according to any one of (1) to ( 8 ), wherein at least a barrier film composed of an inorganic layer / organic layer / inorganic layer is formed on the resin base material, followed by heat treatment.
It is.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail.
In the present invention, by forming a barrier film composed of at least an inorganic layer / organic layer / inorganic layer on a resin base material, it is possible to realize a high water vapor barrier property that is difficult to achieve with only a single inorganic layer. . In particular, by interposing the organic layer between the inorganic layer and the inorganic layer, the organic layer fills and smoothes the defective portion of the layer structure that cannot be eliminated by only the single layer of the inorganic material, and the second inorganic material with few defect points It is considered that a layer is formed and a high water vapor barrier property is obtained. Further, by interposing the organic layer, deterioration of the barrier property against bending can be suppressed.
The organic material layer used in the present invention is not particularly limited as long as it has as a main component a resin obtained by crosslinking a diacrylate having at least one polar group other than an acryloyl group. Since a resin obtained by crosslinking a diacrylate having a polar group has excellent adhesion to an inorganic layer and excellent chemical resistance, a water vapor barrier film using this organic layer is used for organic EL displays and liquid crystal displays. The excellent water vapor barrier property can be maintained through the chemical treatment process and the cleaning process in the manufacturing process.
The polar group possessed by the diacrylate used in the present invention is not particularly limited as long as it improves the adhesion to the inorganic layer, but examples include ether bond, ester bond, urethane bond, amide bond, hydroxyl group, etc. In view of transparency and thermal stability, an ether bond or an ester bond is preferable, and an ether bond is more preferable.
[0008]
Preferred examples of the diacrylate having an ether bond or an ester bond include neopentyl glycol-modified trimethylolpropane diacrylate, epichlorohydrin-modified 1,6-hexanediol diacrylate, polypropylene glycol diacrylate, polyethylene glycol diacrylate, Examples include glycerol diacrylate, caprolactone-modified hydroxypivalate neopentyl glycol diacrylate, hydroxypivalate neopentyl glycol diacrylate, bis (acryloxyneopentyl glycol) adipate, and the like. Among these, diacrylates having a cyclic ether structure such as neopentyl glycol-modified trimethylolpropane diacrylate represented by the general formula (1) having excellent heat resistance are most preferable.
[Chemical 3]

These diacrylates may be used alone or in combination of two or more. If these diacrylates are the main component, monofunctional or trifunctional or higher acrylates and other reactive monomers and / or oligomers may be used. It may be used in combination.
[0009]
The thickness of the organic layer is preferably 0.01 to 5 μm, more preferably 0.05 to 3 μm, and most preferably 0.1 to 2 μm. If the thickness of the organic layer is less than 0.01 μm, the defective portion cannot be filled and the barrier property may be lowered. On the other hand, if the thickness of the organic material layer is larger than 5 μm, the barrier property may be lowered due to water absorption from the end face.
The method for forming the organic material layer is not particularly limited, and a dry process such as vacuum deposition or a wet process such as dip coating, bar coating, or spin coating can be applied. In particular, when the inorganic layer is formed under vacuum, it is preferably formed by vacuum deposition. If the organic material layer is formed by vacuum deposition, the inorganic material layer, the organic material layer, and the inorganic material layer can be laminated continuously under vacuum, which is advantageous in terms of cost.
[0010]
When vacuum deposition is used as a method for forming the organic layer, the diacrylate used for the organic layer preferably has moderate volatility, and considering the volatility, the molecular weight of the diacrylate used for the organic layer is 200 to 1000. It is preferable that More preferably, it is 250-800, More preferably, it is 300-700, Most preferably, it is 300-600. When the molecular weight is lower than 200, the deposition efficiency may decrease as the substrate temperature increases. On the other hand, if the molecular weight exceeds 1000, it is difficult to deposit due to low volatility, and in some cases, it may be cured before being evaporated.
[0011]
Although there is no restriction | limiting in particular as a method of bridge | crosslinking the diacrylate used for an organic substance layer, It is preferable to bridge | crosslink using UV since an installation is cheap and hardening is quick. In this case, it is preferable to add a photopolymerization initiator.
The photopolymerization initiator to be used is not particularly limited. However, when a resin mainly composed of diacrylate is formed by vacuum deposition, it is preferable that the volatility is similar to that of diacrylate.
Examples of photopolymerization initiators include 1-hydroxycyclohexyl phenyl ketone, 2,2-dimethoxy-1,2-diphenylethane-1-one, 2-methyl-1 [4- (methylthio) phenyl] -2-mol Forinopropan-1-one, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1- Examples include propan-1-one and bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide. These photopolymerization initiators may be used alone or in combination of two or more.
[0012]
The addition amount of the photopolymerization initiator is preferably 0.1 to 10 parts by weight with respect to 100 parts by weight of the resin mainly composed of diacrylate. More preferably, it is 0.5-7 weight part, Most preferably, it is 0.8-5 weight part. If the content of the photopolymerization initiator is less than 0.1 parts by weight, curing may be insufficient. On the other hand, if the content of the photopolymerization initiator exceeds 10 parts by weight, curing may occur but a brittle organic layer may be formed.
[0013]
The inorganic layer of the present invention is not particularly limited as long as it is transparent and has a water vapor barrier property. For example, an oxide or nitride containing one or more of Si, Al, In, Sn, Zn, Ti, Cu, Ce, and the like Or oxynitride can be used. In particular, it is preferable to use silicon oxide or silicon oxynitride as the inorganic layer in order to achieve both water vapor barrier properties and high transparency. Silicon oxide is expressed as SiOx. For example, when SiOx is used as the inorganic layer, it is desirable that 1.6 <x <1.9 in order to achieve both good water vapor barrier properties and high light transmittance. Silicon oxynitride is expressed as SiOxNy, but the ratio of x and y should be an oxygen-rich film, and 1 <x <2, 0 <y <1 is preferred, and water vapor barrier properties When importance is attached to improvement, a nitrogen-rich film is preferable, and 0 <x <0.8 and 0.8 <y <1.3. The two inorganic layers may have the same composition or different compositions.
Although the thickness of an inorganic substance layer is not specifically limited, 5 nm-500 nm are preferable. When the thickness is 500 nm or more, there is a risk of cracking due to bending stress, and when the thickness is 5 nm or less, the film may be distributed in an island shape, which may deteriorate the water vapor barrier property.
As a method for forming the inorganic layer, a resistance heating vapor deposition method, an electron beam vapor deposition method, an ion plating method, a CVD method, a sputtering method can be applied, and a target inorganic oxide, inorganic nitride, inorganic nitride oxide can be obtained. If there is no limit.
[0014]
Although the resin base material of the present invention is not particularly limited, for example, polysulfone, polyethersulfone, norbornene resin, polycarbonate, polyarylate, polyacrylate, polyester, polyamide, epoxy resin, polyimide, polyolefin and the like can be used. . In particular, norbornene resins and polyether sulfones having a glass transition temperature of 200 ° C. or higher are preferable because they have good optical properties and high heat resistance, and are not deformed or deteriorated by high-temperature treatment in the organic layer / inorganic layer forming process.
[0015]
In the present invention, an organic layer can also be provided between the resin substrate and the inorganic layer for the purpose of improving the adhesion between the resin substrate and the inorganic layer. The organic material layer in this case is not particularly limited as long as it improves the adhesion between the resin base material and the inorganic material layer. Preferred examples include epoxy acrylate, urethane acrylate, isocyanuric acid acrylate, pentaerythritol acrylate, and trimethylol. Examples include propane acrylate, ethylene glycol acrylate, and polyester acrylate. Among these, it is particularly preferable that the degree of crosslinking is high and the glass transition temperature is 180 ° C. or higher, such as isocyanuric acid acrylate. Moreover, even if it uses independently, 2 or more types may be mixed. Furthermore, PVA-type, EVA-type, polyvinylidene chloride, or a plurality of these resins, which have a relatively barrier property per se, can be used in combination. Although there is no restriction | limiting in particular in the thickness about the organic substance layer directly on the resin base material, 0.01-10 micrometers is preferable.
[0016]
The transparent water vapor barrier film of the present invention is preferably heat-treated after forming a barrier film layer comprising at least an inorganic layer / organic layer / inorganic layer on a resin substrate. By performing the heat treatment, the adhesion between the inorganic layer and the organic layer is improved. The preferred heat treatment temperature differs depending on the base material used and the organic material layer. For example, when polyethersulfone is used for the base material and neopentyl glycol modified trimethylolpropane diacrylate having a cyclic ether structure is used for the organic material layer, Is preferably 100 to 200 ° C, more preferably 120 to 200 ° C.
[0017]
【Example】
Examples of the present invention will be described in detail below, but the present invention is not limited to the following examples.
(Example 1)
A uniform mixed solution consisting of 25% by weight of isocyanuric acid triacrylate (Toa Gosei: Aronix M-315), 50% by weight of diethylene glycol, 24% by weight of ethyl acetate and 1% by weight of silane coupling agent was applied to the polyethersulfone film with a spin coater. After heating and drying at 10 ° C. for 10 minutes, it was further cured by UV irradiation to form a 2 μm resin layer. Next, the film on which the organic layer was formed was set in a vacuum chamber of a film forming apparatus equipped with a high-pressure mercury UV lamp in a vacuum vapor deposition machine equipped with a resistance heating terminal and an electron gun, and was evacuated to a level of 10 ⁻⁴ Pa. Later, a 30 nm silicon nitride oxide film was formed by electron beam evaporation. Thereafter, resistance heating of the organic vapor deposition source was started in a state where the degree of vacuum in the vacuum chamber was stabilized at 10 ⁻⁴ Pa, and when the evaporation of impurities was completed, the vapor deposition shutter was opened to deposit a 500 nm organic layer. The composition of the deposited organic layer was a photopolymerization initiator (Irgacure) in 100 parts by weight of neopentyl glycol-modified trimethylolpropane diacrylate (KAYARAD R-604: manufactured by Nippon Kayaku Co., Ltd.), which is a diacrylate having a cyclic ether structure. -651: Ciba Specialty Chemicals) was used. After returning the deposition shutter, the UV lamp shutter was opened and cured with an integrated light amount of 500 mJ / cm ² . Thereafter, the formation of a 30 nm silicon oxynitride film by electron beam evaporation was repeated until a transparent water vapor barrier film of resin substrate / organic layer (1) / inorganic layer (1) / organic layer (2) / inorganic layer (2) was formed. Formed. The formed transparent water vapor barrier film was subjected to heat treatment (130 ° C. × 1 h + 200 ° C. × 3 h) under vacuum, and then evaluated.
[0018]
(Comparative Example 1)
In the same manner as in Example 1 except that the organic layer (2) sandwiched between the inorganic layer (1) and the inorganic layer (2) is not formed, the organic layer (1) / inorganic layer (1) is formed on the polyethersulfone film. ▼ / Inorganic layer (2) was formed.
[0019]
(Comparative Example 2)
Instead of neopentyl glycol-modified trimethylolpropane diacrylate (KAYARAD R-604: manufactured by Nippon Kayaku Co., Ltd.) used in Example 1, dicyclopentadienyl diacrylate having no polar group other than acryloyl group ( Other than using Aronix M-203 (manufactured by Toagosei Co., Ltd.), an organic layer (1) / inorganic layer (1) / organic layer (2) / inorganic layer on a polyethersulfone film in the same manner as in Example 1. (2) was formed.
[0020]
(Evaluation)
The water vapor permeability of each film was measured by the JISK7129B method. Further, after winding once around a 30 mmφ rod, the water vapor permeability was measured again by the JISK7129B method. Furthermore, after the film was put in a constant temperature and humidity chamber at 60 ° C. and 95% RH for 24 hours, the water vapor permeability was again measured by the JISK7129B method. The results are shown in Table 1.
[0021]
[Table 1]

[0022]
In Example 1, all the evaluation results sufficiently satisfied the required characteristics for the display element, but in Comparative Example 1 in which the organic layer (2) is not formed, two inorganic layers are stacked and the thickness is large. As a result, it is considered that the water vapor permeability is increased compared to the example because it is weak against bending and easily cracked. Further, in Comparative Example 2 in which the organic layer (2) is formed of non-polar diacrylate, the adhesion between the organic layer and the inorganic layer is low, so that the organic matter is obtained by heating and humidifying treatment (60 ° C., 95% RH × 24 h). It is thought that peeling occurred at the interface between the layer and the inorganic layer, and the water vapor permeability increased.
[0023]
【The invention's effect】
The present invention is a transparent film having a high water vapor barrier, and further has a characteristic that the water vapor barrier property does not deteriorate even when subjected to heat humidification and bending. If the film of the present invention is applied as a display element, for example, a light and unbreakable display can be realized. Moreover, if it is applied to the storage of chemicals, it is possible to realize a storage container whose contents can be seen and will not break even if dropped, and its industrial value is extremely high.

Claims (9)

In a transparent water vapor barrier film having a barrier film composed of at least an inorganic layer / organic layer / inorganic layer on a resin substrate, the organic layer is crosslinked with a diacrylate having at least one polar group other than an acryloyl group. A transparent water vapor barrier film comprising a resin as a main component , wherein the diacrylate is a diacrylate having a cyclic ether structure . Transparent water vapor barrier film according to claim 1, wherein the acrylate having a cyclic ether structure is a diacrylate of the general formula (1).

The thickness of the organic material layer, a transparent water vapor barrier film of any one of claims 1 or 2, wherein the at 0.01μm or 5μm or less. The said organic substance layer is formed into a film by vacuum deposition, The transparent water vapor | steam barrier film of any one of Claims 1-3 characterized by the above-mentioned. Transparent water vapor barrier film of any one of claims 1-4, wherein the organic material layer and said formed by cross-linked by UV. The transparent water vapor barrier film according to any one of claims 1 to 5 , wherein the inorganic layer contains silicon oxide, silicon nitride, or silicon nitride oxide as a main component. Transparent water vapor barrier film of any one of claims 1 to 6 glass transition temperature of the resin base material is 200 ° C. or higher. The transparent water vapor barrier film according to any one of claims 1 to 7 , wherein the resin base material contains a polyethersulfone or a norbornene resin as a main component. The method for producing a transparent water vapor barrier film according to any one of claims 1 to 8 , wherein a heat treatment is carried out after forming a barrier film comprising at least an inorganic layer / organic layer / inorganic layer on a resin substrate. .