JP2004107690A - Method for depositing optical thin film, method for producing antireflection film and antireflection film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for depositing optical thin films and a method for producing antireflection films by which optical thin films, particularly antireflection films, can uniformly be deposited with high precision so that the film thickness thereof is made the objective value by using an atmospheric pressure plasma discharge treatment method, and to provide antireflection films which exhibit little reflection and coloring. <P>SOLUTION: In the method for producing antireflection films on continuously transported base materials by an atmospheric pressure plasma discharge treatment method, reflectivity is measured with a reflectivity measuring instrument at two or more wavelengths set inside a visible wavelength region to each deposited antireflection film, and the measured value is arithmetically operated in comparison with the objective reflectivity value. The result is fed-back to a film thickness control system, and each thin film deposition condition of each antireflection layer is controlled. <P>COPYRIGHT: (C)2004,JPO

Description

【００３９】
【表２】

【００４０】
【表３】

【００４１】
更に、もう一つの本発明の別の態様は、着色の制御に関するものであるが、可視光波長領域の全反射スペクトルから色差、もしくは三刺激値に変換して制御するという方法である。中屈折率層／高屈折率層／低屈折率層積層の最上層の低屈折率層を形成している時の着色が最も顕著に現れるので、最終仕上がりの着色という観点からも低屈折率層形成時に制御を行うことが好ましい。しかし、どの波長が着色に関与しているかの判断が難しい場合がある。特に最上層を塗設して仕上げたものは、膜厚の僅かなズレが特定波長で大きくなり、色として人に認識され易くなる。人間が認識する色を数値に置き換えたＬ^＊ａ^＊ｂ^＊色空間からの下記色差の式（ＪＩＳ　Ｚ８７２９に規格化されている色の表示方法）によって求める。
【００４２】
ΔＥ^＊ａｂ＝［（ΔＬ^＊）^２＋（Δａ^＊）^２＋（Δｂ^＊）^２］^１／２
ここで、Ｌ^＊は明度指数、ａ^＊及びｂ^＊は知覚色度指数である。
【００４３】
また、三刺激値（Ｘ、Ｙ、Ｚ）によって色を判断することが出来る。
そこで、本発明において、色は上記色差の式で求める方法、また三刺激値（Ｘ、Ｙ、Ｚ）で求める方法をもう一つの着色を判断する基準として採用した。この方法は、目標の中屈折率層／高屈折率層／低屈折率層積層の全反射スペクトルから色差の式またはＸ、Ｙ、Ｚの三刺激値に変換して、薄膜形成中の低屈折率層の全反射スペクトルの変換した色差の式またはＸ、Ｙ、Ｚの三刺激値とを対比演算して、低屈折率層形成膜厚制御系にフィードバックし、その指令によって制御するものである。
【００４４】
以下、本発明に有用な大気圧プラズマ放電処理装置について説明するが、これらの装置に限定されるものではない。
【００４５】
図２は、本発明に係る大気圧プラズマ放電薄膜形成装置の一例を示す概略図である。図２はプラズマ放電処理装置３０、ガス供給手段５０、電圧印加手段４０、及び電極温度調節手段６０から構成されている。ロール回転電極３５と角筒型固定電極群３６として、基材Ｆをプラズマ放電処理するものである。この図１では、ロール回転電極３５はアース電極で、角筒型固定電極群３６は高周波電源４１に接続されている印加電極である。基材Ｆは図示されていない元巻きから巻きほぐされて搬送して来るか、または前工程から搬送されて来て、ガイドロール６４を経てニップロール６５で基材に同伴して来る空気等を遮断し、ロール回転電極３５に接触したまま巻き回されながら角筒型固定電極群３６との間を移送され、ニップロール６６、ガイドロール６７を経て、図示してない巻き取り機で巻き取られるか、次工程に移送する。透明導電性薄膜用ガスはガス供給手段５０で、ガス発生装置５１で発生させた透明導電性薄膜用ガスＧ（この場合放電ガスと薄膜形成ガスは混合されている）を、流量制御して給気口５２より対向電極間（ここが放電空間になる）３２のプラズマ放電処理容器３１内に入れ、該プラズマ放電処理容器３１内を透明導電性薄膜用ガスＧで充填し、放電処理が行われた処理排ガスＧ′を排気口５３より排出するようにする。次に電圧印加手段４０で、高周波電源４１により角筒型固定電極群３６に電圧を印加し、アース電極のロール回転電極３５との電極間で放電プラズマを発生させる。ロール回転電極３５及び角筒型固定電極群３６を電極温度調節手段６０を用いて媒体を加熱または冷却し電極に送液する。電極温度調節手段６０で温度を調節した媒体を送液ポンプＰで配管６１を経てロール回転電極３５及び角筒型固定電極群３６内側から温度を調節する。プラズマ放電処理の際、基材の温度によって得られる薄膜の物性や組成は変化することがあり、これに対して適宜制御することが好ましい。媒体としては、蒸留水、油等の絶縁性材料が好ましく用いられる。プラズマ放電処理の際、幅手方向あるいは長手方向での基材の温度ムラを出来るだけ生じさせないようにロール回転電極３５の内部の温度を制御することが望ましい。なお、６８及び６９はプラズマ放電処理容器３１と外界を仕切る仕切板である。
【００４６】
図３は、図２に示したロール回転電極の導電性の金属質母材とその上に被覆されている誘電体の構造を示す一例を示す斜視図である。
【００４７】
図３において、ロール電極３５ａの導電性の金属質母材３５Ａで形成されているロールの表面側に誘電体が被覆されており、中は中空になっていて温度調節が行われるジャケットになっている。
【００４８】
図４は、図２に示した角筒型電極の母材とその上に被覆されている誘電体の構造を示す一例を示す斜視図である。
【００４９】
図４において、角筒型電極３６ａは、金属等の導電性の母材に対し、図３同様の誘電体被覆層を有している。角筒型電極３６ａは中空の金属角型のパイプで、パイプの表面に上記と同様の誘電体を被覆し、放電中は温度調節が行えるようになっている。尚、角筒型固定電極群３６の数は、上記ロール回転電極３５の円周より大きな円周上に沿って複数本設置されており、放電面積はロール回転電極３５に相対している角筒型電極３６ａ面の全面積となる。
【００５０】
図４に示した角筒型電極３６ａは、円筒型（丸型）電極に比べて、放電範囲（放電面積）を広げる効果があるので、本発明の薄膜形成方法に好ましく用いられる。
【００５１】
図３及び図４において、ロール電極３５ａ及び角筒型電極３６ａは、導電性の金属質母材３５Ａ及び３６Ａの表面に、誘電体３５Ｂ及び３６Ｂを誘電体被覆層とした構造になっている。誘電体被覆層は、セラミックスを溶射後、無機化合物の封孔材料を用いて封孔処理したセラミックス被覆層である。セラミックス被覆誘電体層の厚さは片肉で１ｍｍである。また、溶射に用いるセラミックス材としては、アルミナやアルミナ・窒化珪素等が好ましく用いられるが、この中でもアルミナが加工し易いので、更に好ましく用いられる。
【００５２】
または、誘電体層として、ガラスライニングによる無機材料のライニング処理誘電体であってもよい。
【００５３】
導電性の金属質母材３５Ａ及び３６Ａとしては、チタン金属またはチタン合金、銀、白金、ステンレススティール、アルミニウム、鉄等の金属等や、鉄とセラミックスとの複合材料またはアルミニウムとセラミックスとの複合材料を挙げることが出来るが、後述の理由からはチタン金属またはチタン合金が好ましい。
【００５４】
対向電極間距離は、導電性の金属質母材に設けた誘電体の厚さ、印加電圧の大きさ、プラズマを利用する目的等を考慮して決定されるが、電極の一方に誘電体を設けた場合には誘電体表面と導電性の金属質母材表面の最短距離、また上記電極の双方に誘電体を設けた場合には誘電体表面同士の距離で、いずれの場合も均一な放電を行う観点から０．５〜２０ｍｍが好ましく、特に好ましくは１±０．５ｍｍである。
【００５５】
本発明に有用な導電性の金属質母材及び誘電体についての詳細については後述する。
【００５６】
プラズマ放電処理容器３１はパイレックス（Ｒ）ガラス製の処理容器等が好ましく用いられるが、電極との絶縁がとれれば金属製を用いることも可能である。例えば、アルミニウムまたは、ステンレススティールのフレームの内面にポリイミド樹脂等を張り付けても良く、該金属フレームにセラミックス溶射を行い絶縁性をとっても良い。
【００５７】
図５は、図２の大気圧プラズマ放電処理装置を４連直列に設置した連続して薄膜を積層する大気圧プラズマ放電処理装置の一例を示す図である。
【００５８】
図５を用いて本発明に有用な膜厚制御手段を有する反射防止フィルムの製造方法を説明する。本発明において、アンワインダー（ロールからのフィルム繰り出し機）ＵＷから繰り出される基材Ｆ上に中屈折率層形成用プラズマ放電処理装置２００で中屈折率層を形成し、中屈折率層の形成が終了した時点で、膜厚制御手段２１０の屈折率測定器の測定ヘッダー（プローブ）２１４で反射率または反射スペクトルを検出し、オンライン反射率測定装置２１５により可視光波長領域の設定した２波長の反射率を測定する。その結果を演算処理装置２１６で目標値との差を演算して、中屈折率層形成膜厚制御系２１７にフィードバックして目標値の中屈折率層を形成するべく、ガス供給手段２５０及び電圧印加手段２４０の条件をチェックして目標値になるようにガス供給手段のガス供給量、薄膜形成ガス濃度、高周波印加電圧、電力密度等を制御して、目標値の膜厚の中屈折率層を形成する。ここで、２３５はロール回転電極、２３６は角筒型固定電極群（ここでは個々の電極については省略してある）である。
【００５９】
次いで、該目標値を有する中屈折率層Ｆ１の上に、高屈折率層形成用プラズマ放電処理装置３００で高屈折率層の形成が終了した時点で、中屈折率層／高屈折率層積層の高屈折率層側から、膜厚制御手段３１０の測定ヘッダー（プローブ）３１４で反射率または反射スペクトルを検出し、オンライン反射率測定装置３１５により可視光波長領域の設定した２波長の反射率を測定する。その結果を演算処理装置３１６で目標値との差を演算して、高屈折率層形成膜厚制御系３１７にフィードバックして目標値の高屈折率層を形成するべく、ガス供給手段３５０及び電圧印加手段３４０の条件をチェックして目標値になるようにガス供給手段のガス供給量、薄膜形成ガス濃度、高周波印加電圧、電力密度等を制御して、目標値の膜厚の中屈折率層を形成する。ここで、３３５はロール回転電極、３３６は角筒型固定電極群（ここでは個々の電極については省略してある）である。
【００６０】
更に、目標値の膜厚を有する上記中屈折率層／高屈折率層積層のフィルムＦ２の高屈折率層上に、低屈折率層形成用プラズマ放電処理装置４００により、低屈折率層の形成が終了した時点での３重層（中屈折率層／高屈折率層／低屈折率層）の反射フィルムＦ３の低屈折率層側から、膜厚制御手段４１０の測定ヘッダー（プローブ）４１４で反射率または反射スペクトルを検出し、オンライン反射率測定装置４１５により可視光波長範囲の設定した少なくとも２波長の反射率を測定する。その結果を演算処理装置４１６で目標値との差を演算して低屈折率層形成膜厚制御系４１７にフィードバックして目標値の低屈折率層を形成するべく、ガス供給手段４５０及び電圧印加手段４４０の条件をチェックして目標値になるようにガス供給手段のガス供給量、薄膜形成ガス濃度、高周波印加電圧、電力密度等を制御して、目標値の膜厚の低屈折率層を形成する。ここで、４３５はロール回転電極、４３６は角筒型固定電極群（ここでは個々の電極については省略してある）である。
【００６１】
更に付け加えて、中屈折率層／高屈折率層／低屈折率層積層を有する基材Ｆ３に、４番目の防汚層形成用プラズマ放電処理装置５００により、低屈折率層の上に防汚層を形成する。ここで、５３５はロール回転電極、５３６は角筒型固定電極群（ここでは個々の電極については省略してある）であり、５５０はガス供給手段、また５４０は高周波電圧印加手段である。
【００６２】
仕上がった中屈折率層／高屈折率層／低屈折率層／防汚層積層の反射防止フィルムＦ４をアンワインダーＷで巻き取り、本発明の反射防止フィルムの製造が終了する。
【００６３】
なお、測定ヘッダー（プローブ）２１４、３１４及び４１４は基材の幅方向に往復移動しながら反射率を検出することが好ましい。
【００６４】
本発明に有用な反射率測定方法は、反射率及び反射スペクトルを使用する方法であり、例えば、大塚電子（株）製の膜厚測定システムＭＣＰＤシリーズ（ＭＣＰＤ検出器と光ファイバーの組み合わせ）を好ましく用いることが出来る。
【００６５】
本発明において、上記測定システムの反射率を測定するプローブは、出来るだけ基材の全長、全幅をカバー出来るように幅方向に往復運動して移動出来るようになっていることが好ましい。また本発明における測定は、最初に形成される中屈折率層の反射率及び反射スペクトルの情報、次の高屈折率層の積層の反射率及び反射スペクトルの情報、更に低屈折率層の積層の情報がそれぞれの段階でフィードバックされ、予め得ているコンピュータ内の情報と照合してそれぞれの層及び積層の全幅にわたって目標反射率になるように制御するようになっている。このように積層した反射防止層を形成中にオンラインでそれぞれの段階で反射率及び反射スペクトルを測定することにより、品質が優れた反射防止フィルムを生産することが出来、更に高収率で得られる安定な生産を可能にするものである。またオンラインで測定プローブにより全長測定することによって、反射防止フィルムの全長にわたる欠陥情報、製品化可能部分情報というような巻き取った長尺のロールの製品情報等により品質情報を知ることが出来、ユーザーに有益な情報を提供することも出来る。
【００６６】
更に、より正確な情報をフィードバックするために、幅方向に測定プローブを少なくとも縦方向に２個以上の複数の測定プローブを測定と移動を交互に繰り返すことによって、それらの複数の測定プローブからの測定データの平均値を得るようにすることが好ましい。
【００６７】
本発明において、反射光を測定する際には、測定室内は光のない暗黒状態とすることが好ましいが、上記膜厚測定システムはそこまでしなくとも反射率を測定出来るようになっているので必ずしも暗黒にすることはなくなっている。また、測定室内のプローブの測定位置は、ロール間隔が狭い、例えば、３００ｍｍ範囲以内でフィルムが振動しないところで測定することが好ましいが、ロールから１０ｍｍ程度以内の範囲内で測定するのがより好ましい。更に、反射光を測定する際、測定位置の基材の前後にアキュムレータを設けて、基材を一時的に停止させて測定してもよい。
【００６８】
次に、本発明に用いる高周波電源、電極、条件について説明する。
本発明に有用な大気圧プラズマ放電処理装置に設置する高周波電源としては、ハイデン研究所製高周波電源（１００ｋＨｚ＊）、パール工業製高周波電源（２００ｋＨｚ）、パール工業製高周波電源（８００ｋＨｚ）、パール工業製高周波電源（２ＭＨｚ）、パール工業製高周波電源（１３．５６ＭＨｚ）、パール工業製高周波電源（２７ＭＨｚ）、パール工業製高周波電源（１５０ＭＨｚ）等の市販のものを挙げることが出来、何れも使用することが出来る。なお、＊印はハイデン研究所インパルス高周波電源（連続モードで１００ｋＨｚ）である。
【００６９】
本発明においては、このような電圧を印加して、均一なグロー放電状態を保つことが出来る電極をプラズマ放電処理装置に採用する必要がある。
【００７０】
本発明において、対向する電極間に印加する電力密度は、１Ｗ／ｃｍ^２以上の電力密度（出力密度）を供給し、放電ガスを励起してプラズマを発生させ、エネルギーを薄膜形成ガスに与え薄膜を形成させる。供給する電力密度の上限値としては、好ましくは５０Ｗ／ｃｍ^２以下、より好ましくは２０Ｗ／ｃｍ^２以下である。下限値は、好ましくは１．２Ｗ／ｃｍ^２以上である。なお、放電面積（ｃｍ^２）は、電極において放電が起こる範囲の面積のことを指す。
【００７１】
ここで電源の印加法に関しては、連続モードと呼ばれる連続サイン波状の連続発振モードと、パルスモードと呼ばれるＯＮ／ＯＦＦを断続的に行う断続発振モードのどちらを採用してもよいが、連続サイン波の方がより緻密で良質な膜が得られるので好ましい。
【００７２】
このような大気圧プラズマによる薄膜形成法に使用する電極は、構造的にも、性能的にも過酷な条件に耐えられるものでなければならない。このような電極としては、金属質母材上に誘電体を被覆したものであることが好ましい。
【００７３】
本発明に使用する誘電体被覆電極においては、様々な金属質母材と誘電体との間に特性が合うものが好ましく、その一つの特性として、金属質母材と誘電体との線熱膨張係数の差が１０×１０^−６／℃以下となる組み合わせのものである。好ましくは８×１０^−６／℃以下、更に好ましくは５×１０^−６／℃以下、更に好ましくは２×１０^−６／℃以下である。なお、線熱膨張係数とは、周知の材料特有の物性値である。
【００７４】
線熱膨張係数の差が、この範囲にある導電性の金属質母材と誘電体との組み合わせとしては、
▲１▼金属質母材が純チタンまたはチタン合金で、誘電体がセラミックス溶射被膜
▲２▼金属質母材が純チタンまたはチタン合金で、誘電体がガラスライニング
▲３▼金属質母材がステンレススティールで、誘電体がセラミックス溶射被膜
▲４▼金属質母材がステンレススティールで、誘電体がガラスライニング
▲５▼金属質母材がセラミックスおよび鉄の複合材料で、誘電体がセラミックス溶射被膜
▲６▼金属質母材がセラミックスおよび鉄の複合材料で、誘電体がガラスライニング
▲７▼金属質母材がセラミックスおよびアルミの複合材料で、誘電体がセラミックス溶射皮膜
▲８▼金属質母材がセラミックスおよびアルミの複合材料で、誘電体がガラスライニング
等がある。線熱膨張係数の差という観点では、上記▲１▼または▲２▼および▲５▼〜▲８▼が好ましく、特に▲１▼が好ましい。
【００７５】
本発明において、金属質母材は、上記の特性からはチタンまたはチタン合金が特に有用である。金属質母材をチタンまたはチタン合金とすることにより、誘電体を上記とすることにより、使用中の電極の劣化、特にひび割れ、剥がれ、脱落等がなく、過酷な条件での長時間の使用に耐えることが出来る。
【００７６】
本発明に有用な電極の金属質母材は、チタンを７０質量％以上含有するチタン合金またはチタン金属である。本発明において、チタン合金またはチタン金属中のチタンの含有量は、７０質量％以上であれば、問題なく使用出来るが、好ましくは８０質量％以上のチタンを含有しているものが好ましい。本発明に有用なチタン合金またはチタン金属は、工業用純チタン、耐食性チタン、高力チタン等として一般に使用されているものを用いることが出来る。工業用純チタンとしては、ＴＩＡ、ＴＩＢ、ＴＩＣ、ＴＩＤ等を挙げることが出来、何れも鉄原子、炭素原子、窒素原子、酸素原子、水素原子等を極僅か含有しているもので、チタンの含有量としては、９９質量％以上を有している。耐食性チタン合金としては、Ｔ１５ＰＢを好ましく用いることが出来、上記含有原子の他に鉛を含有しており、チタン含有量としては、９８質量％以上である。また、チタン合金としては、鉛を除く上記の原子の他に、アルミニウムを含有し、その他バナジウムや錫を含有しているＴ６４、Ｔ３２５、Ｔ５２５、ＴＡ３等を好ましく用いることが出来、これらのチタン含有量としては、８５質量％以上を含有しているものである。これらのチタン合金またはチタン金属はステンレススティール、例えばＡＩＳＩ３１６に比べて、熱膨張係数が１／２程度小さく、金属質母材としてチタン合金またはチタン金属の上に施された後述の誘電体との組み合わせがよく、高温、長時間での使用に耐えることが出来る。
【００７７】
一方、誘電体の求められる特性としては、具体的には、比誘電率が６〜４５の無機化合物であることが好ましく、また、このような誘電体としては、アルミナ、窒化珪素等のセラミックス、あるいは、ケイ酸塩系ガラス、ホウ酸塩系ガラス等のガラスライニング材等がある。この中では、後述のセラミックスを溶射したものやガラスライニングにより設けたものが好ましい。特にアルミナを溶射して設けた誘電体が好ましい。
【００７８】
または、上述のような大電力に耐える仕様の一つとして、誘電体の空隙率が１０体積％以下、好ましくは８体積％以下であることで、好ましくは０体積％を越えて５体積％以下である。なお、誘電体の空隙率は、ＢＥＴ吸着法や水銀ポロシメーターにより測定することが出来る。後述の実施例においては、島津製作所製の水銀ポロシメーターにより金属質母材に被覆された誘電体の破片を用い、空隙率を測定する。誘電体が、低い空隙率を有することにより、高耐久性が達成される。このような空隙を有しつつも空隙率が低い誘電体としては、後述の大気圧プラズマ溶射法等による高密度、高密着のセラミックス溶射被膜等を挙げることが出来る。更に空隙率を下げるためには、封孔処理を行うことが好ましい。
【００７９】
上記、大気圧プラズマ溶射法は、セラミックス等の微粉末、ワイヤ等をプラズマ熱源中に投入し、溶融または半溶融状態の微粒子として被覆対象の金属質母材に吹き付け、皮膜を形成させる技術である。プラズマ熱源とは、分子ガスを高温にし、原子に解離させ、更にエネルギーを与えて電子を放出させた高温のプラズマガスである。このプラズマガスの噴射速度は大きく、従来のアーク溶射やフレーム溶射に比べて、溶射材料が高速で金属質母材に衝突するため、密着強度が高く、高密度な被膜を得ることが出来る。詳しくは、特開２０００−３０１６５５に記載の高温被曝部材に熱遮蔽皮膜を形成する溶射方法を参照することが出来る。この方法により、上記のような被覆する誘電体（セラミック溶射膜）の空隙率にすることが出来る。
【００８０】
また、大電力に耐える別の好ましい仕様としては、誘電体の厚みが０．５〜２ｍｍであることである。この膜厚変動は、５％以下であることが望ましく、好ましくは３％以下、更に好ましくは１％以下である。
【００８１】
誘電体の空隙率をより低減させるためには、上記のようにセラミックス等の溶射膜に、更に、無機化合物で封孔処理を行うことが好ましい。前記無機化合物としては、金属酸化物が好ましく、この中では特に酸化ケイ素（ＳｉＯ_ｘ）を主成分として含有するものが好ましい。
【００８２】
封孔処理の無機化合物は、ゾルゲル反応により硬化して形成したものであることが好ましい。封孔処理の無機化合物が金属酸化物を主成分とするものである場合には、金属アルコキシド等を封孔液として前記セラミック溶射膜上に塗布し、ゾルゲル反応により硬化する。無機化合物がシリカを主成分とするものの場合には、アルコキシシランを封孔液として用いることが好ましい。
【００８３】
ここでゾルゲル反応の促進には、エネルギー処理を用いることが好ましい。エネルギー処理としては、熱硬化（好ましくは２００℃以下）や、紫外線照射などがある。更に封孔処理の仕方として、封孔液を希釈し、コーティングと硬化を逐次で数回繰り返すと、よりいっそう無機質化が向上し、劣化の無い緻密な電極が出来る。
【００８４】
本発明に係る誘電体被覆電極の金属アルコキシド等を封孔液として、セラミックス溶射膜にコーティングした後、ゾルゲル反応で硬化する封孔処理を行う場合、硬化した後の金属酸化物の含有量は６０モル％以上であることが好ましい。封孔液の金属アルコキシドとしてアルコキシシランを用いた場合には、硬化後のＳｉＯ_ｘ（ｘは２以下）含有量が６０モル％以上であることが好ましい。硬化後のＳｉＯ_ｘ含有量は、ＸＰＳにより誘電体層の断層を分析することにより測定する。
【００８５】
本発明の薄膜形成方法に係る電極においては、電極の少なくとも基材と接する側のＪＩＳ　Ｂ　０６０１で規定される表面粗さの最大高さ（Ｒｍａｘ）が１０μｍ以下になるように制御することが、本発明に記載の効果を得る観点から好ましいが、更に好ましくは、表面粗さの最大値が８μｍ以下であり、特に好ましくは、７μｍ以下に制御することである。このように誘電体被覆電極の誘電体表面を研磨仕上げする等の方法により、誘電体の厚み及び電極間のギャップを一定に保つことが出来、放電状態を安定化出来ること、更に熱収縮差や残留応力による歪やひび割れを無くし、且つ、高精度で、耐久性を大きく向上させることが出来る。誘電体表面の研磨仕上げは、少なくとも基材と接する側の誘電体において行われることが好ましい。更にＪＩＳ　Ｂ　０６０１で規定される中心線平均表面粗さ（Ｒａ）は０．５μｍ以下が好ましく、更に好ましくは０．１μｍ以下である。
【００８６】
本発明に使用する誘電体被覆電極において、大電力に耐える他の好ましい仕様としては、耐熱温度が１００℃以上であることである。更に好ましくは１２０℃以上、特に好ましくは１５０℃以上である。また上限は５００℃である。なお、耐熱温度とは、絶縁破壊が発生せず、正常に放電出来る状態において耐えられる最も高い温度のことを指す。このような耐熱温度は、上記のセラミックス溶射や、泡混入量の異なる層状のガラスライニングで設けた誘電体を適用したり、下記金属質母材と誘電体の線熱膨張係数の差の範囲内の材料を適宜選択する手段を適宜組み合わせることによって達成可能である。
【００８７】
次に、本発明の薄膜を形成するガスについて説明する。使用するガスは、基本的に放電ガス及び薄膜形成ガスを構成成分とするガスである。放電ガスと薄膜形成ガスを混合して放電空間または処理空間に供給してもよいし、前述のように別の態様として、別々に供給してもかまわない。別々に供給する場合の放電ガスと薄膜形成ガスとの処理空間における比率は１００：１〜５：１が好ましい。この比率は薄膜を基材上に形成される場、つまり放電空間または処理空間である。別々に供給する場合の薄膜形成ガスは、薄膜形成ガスだけで放電空間または処理空間に供給出来ないので、薄膜形成ガスを不活性なガスの中でバブリングして、気化することによって供給し易くなる。この時の不活性ガス（放電ガスと同様なガスでもよい）を９８．０〜９９．１体積％、薄膜形成ガスを０．９から２．０体積％程度の割合が好ましい。
【００８８】
放電ガスとは、薄膜形成可能なグロー放電を起こすことの出来るガスであり、それ自身がエネルギーを授受する媒体として働く。放電ガスとしては、窒素、希ガス、空気、水素ガス、酸素などがあり、これらを単独で放電ガスとして用いても、混合して用いてもかまわない。希ガスとしては、周期表の第１８属元素、具体的には、ヘリウム、ネオン、アルゴン、クリプトン、キセノン、ラドン等を挙げることが出来る。また、放電ガスの量は、放電空間または処理空間に供給する全ガス量に対し、９０．０〜９９．９体積％含有することが好ましい。
【００８９】
次に、本発明の高機能薄膜を形成する放電処理用ガスについて説明する。使用する放電処理用ガスは、基本的に放電ガス及び薄膜形成ガスで構成するガスである。
【００９０】
薄膜形成ガスは、放電空間で放電ガスからエネルギーを受け励起状態またはプラズマ状態となり、高機能薄膜を形成するガスであり、または反応を制御したり、反応を促進したりするガスでもある。
【００９１】
本発明においては、薄膜形成ガスは少なくとも有機金属化合物を含有している。また有機金属化合物から形成される金属酸化物にドーピングするドーピング用有機金属化合物を加える場合があり、同様な有機金属化合物が使用される。
【００９２】
本発明に有用な有機金属化合物は下記の一般式（Ｉ）で示すものが好ましい。一般式（Ｉ）　Ｒ^１ _ｘＭＲ^２ _ｙＲ^３ _ｚ
式中、Ｍは金属、Ｒ^１はアルキル基、Ｒ^２はアルコキシ基、Ｒ^３はβ−ジケトン錯体基、β−ケトカルボン酸エステル錯体基、β−ケトカルボン酸錯体基及びケトオキシ基（ケトオキシ錯体基）から選ばれる基であり、金属Ｍの価数をｍとした場合、ｘ＋ｙ＋ｚ＝ｍであり、ｘ＝０〜ｍ、またはｘ＝０〜ｍ−１であり、ｙ＝０〜ｍ、ｚ＝０〜ｍで、何れも０または正の整数である。Ｒ^１のアルキル基としては、メチル基、エチル基、プロピル基、ブチル基等を挙げることが出来る。Ｒ^２のアルコキシ基としては、例えばメトキシ基、エトキシ基、プロポキシ基、ブトキシ基、３，３，３−トリフルオロプロポキシ基等を挙げることが出来る。またアルキル基の水素原子をフッ素原子に置換したものでもよい。Ｒ^３のβ−ジケトン錯体基、β−ケトカルボン酸エステル錯体基、β−ケトカルボン酸錯体基及びケトオキシ基（ケトオキシ錯体基）から選ばれる基としては、β−ジケトン錯体基として、例えば、２，４−ペンタンジオン（アセチルアセトンあるいはアセトアセトンともいう）、１，１，１，５，５，５−ヘキサメチル−２，４−ペンタンジオン、２，２，６，６−テトラメチル−３，５−ヘプタンジオン、１，１，１−トリフルオロ−２，４−ペンタンジオン等を挙げることが出来、β−ケトカルボン酸エステル錯体基として、例えば、アセト酢酸メチルエステル、アセト酢酸エチルエステル、アセト酢酸プロピルエステル、トリメチルアセト酢酸エチル、トリフルオロアセト酢酸メチル等を挙げることが出来、β−ケトカルボン酸として、例えば、アセト酢酸、トリメチルアセト酢酸等を挙げることが出来、またケトオキシとして、例えば、アセトオキシ基（またはアセトキシ基）、プロピオニルオキシ基、ブチリロキシ基、アクリロイルオキシ基、メタクリロイルオキシ基等を挙げることが出来る。これらの基の炭素原子数は、上記例有機金属示化合物を含んで、１８以下が好ましい。また例示にもあるように直鎖または分岐のもの、また水素原子をフッ素原子に置換したものでもよい。
【００９３】
本発明において取り扱いの問題から、爆発の危険性の少ない有機金属化合物が好ましく、分子内に少なくとも一つ以上の酸素を有する有機金属化合物が好ましい。このようなものとしてＲ^２のアルコキシ基を少なくとも一つを含有する有機金属化合物、またＲ^３のβ−ジケトン錯体基、β−ケトカルボン酸エステル錯体基、β−ケトカルボン酸錯体基及びケトオキシ基（ケトオキシ錯体基）から選ばれる基を少なくとも一つ有する金属化合物が好ましい。
【００９４】
なお、具体的な有機金属化合物については後述する。
本発明において、放電空間に供給するガスには、放電ガス、薄膜形成ガスの他に、薄膜形成の反応を促進する補助ガス（または添加ガス）を混合してもよい。補助ガスとしては、酸素、オゾン、過酸化水素、二酸化炭素、一酸化炭素、水素、アンモニア等を挙げることが出来るが、酸素、一酸素化炭素及び水素が好ましく、これらから選択される成分を混合させるのが好ましい。その含有量は放電処理用ガスに対して０．０１〜５体積％含有させることにより、反応促進され、且つ、緻密で良質な薄膜を形成することが出来る。
【００９５】
上記形成された酸化物または複合化合物の薄膜の膜厚は、０．１〜１０００ｎｍの範囲が好ましい。
【００９６】
本発明において、薄膜形成ガスに使用する上記有機金属化合物の一般式（Ｉ）、ハロゲン化金属、または金属水素化合物の金属として、Ｌｉ、Ｂｅ、Ｂ、Ｎａ、Ｍｇ、Ａｌ、Ｓｉ、Ｋ、Ｃａ、Ｓｃ、Ｔｉ、Ｖ、Ｃｒ、Ｍｎ、Ｆｅ、Ｃｏ、Ｎｉ、Ｃｕ、Ｚｎ、Ｇａ、Ｇｅ、Ｒｂ、Ｓｒ、Ｙ、Ｚｒ、Ｎｂ、Ｍｏ、Ｃｄ、Ｉｎ、Ｉｒ、Ｓｎ、Ｓｂ、Ｃｓ、Ｂａ、Ｌａ、Ｈｆ、Ｔａ、Ｗ、Ｔｌ、Ｐｂ、Ｂｉ、Ｃｅ、Ｐｒ、Ｎｄ、Ｐｍ、Ｅｕ、Ｇｄ、Ｔｂ、Ｄｙ、Ｈｏ、Ｅｒ、Ｔｍ、Ｙｂ、Ｌｕ等を挙げることが出来る。
【００９７】
本発明の薄膜形成方法で、上記のような有機金属化合物、ハロゲン金属化合物、金属水素化合物等の金属化合物を放電ガスと共に使用することにより様々な高機能性の薄膜を得ることが出来る。本発明の薄膜の例を以下に示すが、本発明はこれに限られるものではない。
【００９８】
電極膜　Ａｕ、Ａｌ、Ａｇ、Ｔｉ、Ｔｉ、Ｐｔ、Ｍｏ、Ｍｏ−Ｓｉ
誘電体保護膜　ＳｉＯ_２、ＳｉＯ、Ｓｉ_３Ｎ_４、Ａｌ_２Ｏ_３、Ａｌ_２Ｏ_３、Ｙ_２Ｏ_３
透明導電膜　Ｉｎ_２Ｏ_３、ＳｎＯ_２
エレクトロクロミック膜　ＷＯ_３、ＩｒＯ_２、ＭｏＯ_３、Ｖ_２Ｏ_５
蛍光膜　ＺｎＳ、ＺｎＳ＋ＺｎＳｅ、ＺｎＳ＋ＣｄＳ
磁気記録膜　Ｆｅ−Ｎｉ、Ｆｅ−Ｓｉ−Ａｌ、γ−Ｆｅ_２Ｏ_３、Ｃｏ、Ｆｅ_３Ｏ_４、Ｃｒ、ＳｉＯ_２、ＡｌＯ_３
超導電膜　Ｎｂ、Ｎｂ−Ｇｅ、ＮｂＮ
太陽電池膜　ａ−Ｓｉ、Ｓｉ
反射膜　Ａｇ、Ａｌ、Ａｕ、Ｃｕ
選択性吸収膜　ＺｒＣ−Ｚｒ
選択性透過膜　Ｉｎ_２Ｏ_３、ＳｎＯ_２
反射防止膜　ＳｉＯ_２、ＴｉＯ_２、ＳｎＯ_２、Ｓｎ−Ｉｎ_２Ｏ_３（ＩＴＯ）、Ｆ−ＳｎＯ_２（ＦＴＯ）、Ｚｎ−Ｉｎ_２Ｏ_３（ＩＺＯ）
シャドーマスク　Ｃｒ
耐摩耗性膜　Ｃｒ、Ｔａ、Ｐｔ、ＴｉＣ、ＴｉＮ
耐食性膜　Ａｌ、Ｚｎ、Ｃｄ、Ｔａ、Ｔｉ、Ｃｒ
耐熱膜　Ｗ、Ｔａ、Ｔｉ
潤滑膜　ＭｏＳ_２
装飾膜　Ｃｒ、Ａｌ、Ａｇ、Ａｕ、ＴｉＣ、Ｃｕ
本発明において、特に好ましい金属化合物の金属は、上記のうちＳｉ（珪素）、Ｔｉ（チタン）、Ｓｎ（錫）、Ｚｎ（亜鉛）、Ｉｎ（インジウム）及びＡｌ（アルミニウム）であり、これらの金属と結合する金属化合物のうち、上記一般式（Ｉ）で示した有機金属化合物が好ましい。有機金属化合物の例示については後述する。
【００９９】
ここで、上記の薄膜のうち反射防止膜（層）及び反射防止膜を積層した反射防止フィルム及び透明導電フィルムについて詳細に説明する。
【０１００】
本発明に係る薄膜のうちの反射防止フィルムの反射防止層は中屈折率層、高屈折率層、低屈折率層それぞれの薄膜が積層されたものである。
【０１０１】
本発明に係る反射防止層薄膜形成ガスの高屈折率層を形成するチタン化合物、中屈折率層を形成する錫化合物、低屈折率層を形成する珪素化合物について述べる。反射防止層を有する反射防止フィルムは、各屈折率層を基材上に直接または他の層を介して積層して得られるものであるが、積層は、例えば、図２〜５のような大気圧プラズマ放電処理装置を、中屈折率層、高屈折率層、低屈折率層の順に３層を積層するために、直列に３基並べて連続的に処理することが出来、この連続的積層処理は品質の安定や生産性の向上等から本発明の薄膜の形成に適している。また積層せずに、１層処理ごと、処理後巻き取り、逐次処理して積層してもよい。本発明において、反射防止層の上に防汚層を設ける場合には、上記のプラズマ放電処理装置を更にもう１基続けて設置し、４基並べて最後に防汚層を積層してもよい。また、反射防止層を設ける前に、基材の上に予めハードコート層や防眩層を塗布によって設けてもよく、また、その裏側に予めバックコート層を塗布によって設けてもよい。
【０１０２】
本発明に係る反射防止フィルムの反射防止層薄膜形成ガスには、適切な屈折率を得ることの出来る化合物であれば制限なく使用出来るが、本発明において、高屈折率層薄膜形成ガスとしてはチタン化合物を、中屈折率層薄膜形成ガスとしては錫化合物またはチタン化合物と珪素化合物の混合物（または高屈折率形成用のチタン化合物で形成した層と低屈折率層を形成する珪素化合物で形成した層を積層してもよい）を、また低屈折率層薄膜形成ガスとしては珪素化合物、フッ素化合物、あるいは珪素化合物とフッ素化合物の混合物を好ましく用いることが出来る。これらの化合物を屈折率を調節するために、何れかの層に用いる薄膜形成ガスを２種以上混合して使用してもよい。
【０１０３】
本発明に有用な中屈折率層薄膜形成ガスに用いる錫化合物としては、有機錫化合物、錫水素化合物、ハロゲン化錫等であり、有機錫化合物としては、例えば、ジブチルジエトキシ錫、ブチル錫トリス（２，４−ペンタンジオナート）、テトラエトキシ錫、メチルトリエトキシ錫、ジエチルジエトキシ錫、トリイソプロピルエトキシ錫、エチルエトキシ錫、メチルメトキシ錫、イソプロピルイソプロポキシ錫、テトラブトキシ錫、ジエトキシ錫、ジメトキシ錫、ジイソプロポキシ錫、ジブトキシ錫、ジブチリロキシ錫、ジエチル錫、テトラブチル錫、錫ビス（２，４−ペンタンジオナート）、エチル錫アセトアセトナート、エトキシ錫（２，４−ペンタンジオナート）、ジメチル錫ジ（２，４−ペンタンジオナート）、ジアセトメチルアセタート錫、ジアセトキシ錫、ジブトキシジアセトキシ錫、ジアセトオキシ錫ジアセトアセトナート等、錫水素化合物等、ハロゲン化錫としては、二塩化錫、四塩化錫等を挙げることが出来、何れも本発明において、好ましく用いることが出来る。また、これらの薄膜形成ガスを２種以上同時に混合して使用してもよい。なお、このようにして、形成された酸化錫層は表面比抵抗値を１０^１１Ω／ｃｍ^２以下に下げることが出来るため、帯電防止層としても有用である。
【０１０４】
本発明に有用な高屈折率層薄膜形成ガスに使用するチタン化合物としては、有機チタン化合物、チタン水素化合物、ハロゲン化チタン等があり、有機チタン化合物としては、例えば、トリエトキシチタン、トリメトキシチタン、トリイソプロポキシチタン、トリブトキシチタン、テトラエトキシチタン、テトライソプロポキシチタン、メチルジメトキシチタン、エチルトリエトキシチタン、メチルトリイソプロポキシチタン、トリエチルチタン、トリイソプロピルチタン、トリブチルチタン、テトラエチルチタン、テトライソプロピルチタン、テトラブチルチタン、テトラジメチルアミノチタン、ジメチルチタンジ（２，４−ペンタンジオナート）、エチルチタントリ（２，４−ペンタンジオナート）、チタントリス（２，４−ペンタンジオナート）、チタントリス（アセトメチルアセタート）、トリアセトキシチタン、ジプロポキシプロピオニルオキシチタン等、ジブチリロキシチタン、チタン水素化合物としてはモノチタン水素化合物、ジチタン水素化合物等、ハロゲン化チタンとしては、トリクロロチタン、テトラクロロチタン等を挙げることが出来、何れも本発明において好ましく用いることが出来る。またこれらの薄膜形成ガスを２種以上を同時に混合して使用することが出来る。
【０１０５】
本発明に有用な低屈折率層薄膜形成ガスに使用する珪素化合物としては、有機珪素化合物、珪素水素化合物、ハロゲン化珪素化合物等を挙げることが出来、有機珪素化合物としては、例えば、テトラエチルシラン、テトラメチルシラン、テトライソプロピルシラン、テトラブチルシラン、テトラエトキシシラン、テトライソプロポキシシラン、テトラブトキシシラン、ジメチルジメトキシシラン、ジエチルジエトキシシラン、ジエチルシランジ（２，４−ペンタンジオナート）、メチルトリメトキシシラン、メチルトリエトキシシラン、エチルトリエトキシシラン等、珪素水素化合物としては、テトラ水素化シラン、ヘキサ水素化ジシラン等、ハロゲン化珪素化合物としては、テトラクロロシラン、メチルトリクロロシラン、ジエチルジクロロシラン等を挙げることが出来、何れも本発明において好ましく用いることが出来る。また、前記フッ素化合物を使用することが出来る。これらの薄膜形成ガスを２種以上を同時に混合して使用することが出来る。また、屈折率の制御にこれら錫化合物、チタン化合物、珪素化合物を適宜２種以上同時に混合して使用してもよい。
【０１０６】
上記の有機錫化合物、有機チタン化合物または有機珪素化合物は、取り扱い上の観点から金属水素化合物、アルコキシ金属が好ましく、腐食性、有害ガスの発生がなく、工程上の汚れなども少ないことから、アルコキシ金属が好ましく用いられる。また、上記の有機錫化合物、有機チタン化合物または有機珪素化合物を放電空間である電極間に導入するには、両者は常温常圧で、気体、液体、固体何れの状態であっても構わない。気体の場合は、そのまま放電空間に導入出来るが、液体、固体の場合は、加熱、減圧、超音波照射等の手段により気化させて使用される。有機錫化合物、有機チタン化合物または有機珪素化合物を加熱により気化して用いる場合、テトラエトキシ金属、テトライソプロポキシ金属などの常温で液体で、沸点が２００℃以下である金属アルコキシドが反射防止膜の形成に好適に用いられる。上記アルコキシ金属は、溶媒によって希釈して使用されても良く、この場合、希ガス中へ気化器等により気化して混合ガスに使用すればよい。溶媒としては、メタノール、エタノール、イソプロパノール、ブタノール、ｎ−ヘキサンなどの有機溶媒及びこれらの混合溶媒が使用出来る。
【０１０７】
薄膜形成ガスについて、放電プラズマ処理により基材上に均一な薄膜を形成する観点から、混合ガス中の含有率は、０．０１〜１０体積％で有することが好ましいが、更に好ましくは、０．０１〜１体積％である。
【０１０８】
なお、中屈折率層については、上記珪素化合物、上記チタン化合物または上記錫化合物を、目標とする屈折率に合わせて適宜混合することによっても得ることが出来る。
【０１０９】
なお、各屈折率層の好ましい屈折率と膜厚は、例えば、中屈折率層の酸化錫層では屈折率として１．６〜１．８、また膜厚として５０〜７０ｎｍ程度、高屈折率層の酸化チタン層では屈折率として１．９〜２．４、また膜厚として８０〜１２０ｎｍ程度、低屈折率層の酸化珪素層では屈折率として１．３〜１．５、また膜厚として８０〜１２０ｎｍ程度である。
【０１１０】
次に本発明に係る薄膜の他の例として透明導電膜を有する薄膜の形成について説明する。
【０１１１】
前述の反射防止層を形成する際に使用する有機金属化合物の金属成分がインジウム等の透明性と導電性を有する薄膜を形成すると言う点が若干異なるが、有機基についてはほぼ同じような成分が用いられる。
【０１１２】
透明導電膜を形成する好ましい有機金属化合物の金属は、インジウム（Ｉｎ）、亜鉛（Ｚｎ）及び錫（Ｓｎ）から選ばれる少なくとも１種の金属である。
【０１１３】
本発明において、好ましい有機金属化合物の好ましい例は、インジウムトリス（２，４−ペンタンジオナート）、インジウムトリス（ヘキサフルオロペンタンジオナート）、インジウムトリアセトアセタート、トリアセトキシインジウム、ジエトキシアセトキシインジウム、トリイソポロポキシインジウム、ジエトキシインジウム（１，１，１−トリフルオロペンタンジオナート）、トリス（２，２，６，６−テトラメチル−３，５−ヘプタンジオナート）インジウム、エトキシインジウムビス（アセトメチルアセタート）、ジ（ｎ）ブチル錫ビス（２，４−ペンタンジオナート）、ジ（ｎ）ブチルジアセトキシ錫、ジ（ｔ）ブチルジアセトキシ錫、テトライソプロポキシ錫、テトラ（ｉ）ブトキシ錫、ビス（２，４−ペンタンジオナート）亜鉛等を挙げることが出来る。これらの有機金属化合物は一般に市販（例えば、東京化成工業（株）等から）されている。
【０１１４】
本発明においては、上記分子内に少なくとも１つの酸素原子を有する有機金属化合物の他に、該有機金属化合物から形成された透明導電膜の導電性を更に高めるために該透明導電膜をドーピングすることが好ましく、薄膜形成ガスとしての該有機金属化合物とドーピング用有機金属化合物ガスを同時に混合して用いることが好ましい。ドーピングに用いられる有機金属化合物またはフッ素化合物の薄膜形成ガスとしては、例えば、トリイソプロポキシアルミニウム、トリス（２，４−ペンタンジオナート）ニッケル、ビス（２，４−ペンタンジオナート）マンガン、イソプロポキシボロン
、トリ（ｎ）ブトキシアンチモン、トリ（ｎ）ブチルアンチモン、ジ（ｎ）ブチルビス（２，４−ペンタンジオナート）錫、ジ（ｎ）ブチルジアセトキシ錫、ジ（ｔ）ブチルジアセトキシ錫、テトライソプロポキシ錫、テトラブトキシ錫、テトラブチル錫、亜鉛ジ（２，４−ペンタンジオナート）、六フッ化プロピレン、八フッ化シクロブタン、四フッ化メタン等を挙げることが出来る。
【０１１５】
前記透明導電膜を形成するに必要な有機金属化合物と上記ドーピング用の薄膜形成ガスの比は、製膜する透明導電膜の種類により異なるが、例えば、酸化インジウムに錫をドーピングして得られるＩＴＯ膜においては、ＩｎとＳｎの比の原子数比が１００：０．１〜１００：１５の範囲になるように薄膜形成ガス量を制御することが必要である。好ましくは、１００：０．５〜１００：１０になるよう制御することが好ましい。酸化錫にフッ素をドーピングして得られる透明導電膜（ＦＴＯ膜という）においては、得られたＦＴＯ膜のＳｎとＦの比の原子数比が１００：０．０１〜１００：５０の範囲になるよう薄膜形成ガスの量比を制御することが好ましい。Ｉｎ_２Ｏ_３−ＺｎＯ系アモルファス透明導電膜においては、ＩｎとＺｎの比の原子数比が１００：５０〜１００：５の範囲になるよう薄膜形成ガスの量比を制御することが好ましい。Ｉｎ：Ｓｎ比、Ｓｎ：Ｆ比及びＩｎ：Ｚｎ比の各原子数比はＸＰＳ測定によって求めることが出来る。
【０１１６】
本発明において、透明導電薄膜形成ガスは、混合ガスに対し、０．０１〜１０体積％含有させることが好ましい。
【０１１７】
本発明において、得られる透明導電膜は、例えば、ＳｎＯ_２、Ｉｎ_２Ｏ_３、ＺｎＯの酸化物膜、またはＳｂドープＳｎＯ_２、ＦドープＳｎＯ_２（ＦＴＯ）、ＡｌドープＺｎＯ、ＳｎドープＩｎ_２Ｏ_３（ＩＴＯ）等ドーパントによるドーピングした複合酸化物を挙げることが出来、これらから選ばれる少なくとも一つを主成分とするアモルファス膜が好ましい。またその他にカルコゲナイド、ＬａＢ_６、ＴｉＮ、ＴｉＣ等の非酸化物膜、Ｐｔ、Ａｕ、Ａｇ、Ｃｕ等の金属膜、ＣｄＯ等の透明導電膜を挙げることが出来る。
【０１１８】
上記形成された酸化物または複合酸化物の透明導電膜の膜厚は、０．１〜１０００ｎｍの範囲が好ましい。
【０１１９】
本発明に用いられる基材について説明する。
本発明に用いられる基材としては、シート状またはフィルム状の平面形状のもので、連続的に移送する状態で薄膜をプラズマ状態の混合ガスに晒し、該基材表面に形成出来るものであれば特に限定はない。具体的には、樹脂レンズ、樹脂フィルム、樹脂シート等を挙げることが出来る。
【０１２０】
樹脂フィルムは本発明に係る大気圧プラズマ放電処理装置の電極間または電極の近傍を連続的に移送させて薄膜を形成することが出来るので、スパッタリングのような真空系のようなバッチ式でない、大量生産に向き、連続的な生産性の高い生産方式として好適である。
【０１２１】
樹脂フィルムまたは樹脂シートの材質としては、セルローストリアセテート、セルロースジアセテート、セルロースアセテートプロピオネートまたはセルロースアセテートブチレートのようなセルロースエステル、ポリエチレンテレフタレートやポリエチレンナフタレートのようなポリエステル、ポリエチレンやポリプロピレンのようなポリオレフィン、ポリ塩化ビニリデン、ポリ塩化ビニル、ポリビニルアルコール、エチレンビニルアルコールコポリマー、シンジオタクティックポリスチレン、ポリカーボネート、ノルボルネン樹脂、ポリメチルペンテン、ポリエーテルケトン、ポリイミド、ポリエーテルスルフォン、ポリスルフォン、ポリエーテルイミド、ポリアミド、フッ素樹脂、ポリメチルアクリレート、アクリレートコポリマー等を挙げることが出来る。
【０１２２】
これらの素材は単独であるいは適宜混合されて使用することも出来る。中でもゼオネックスやゼオノア（日本ゼオン（株）製）、非晶質シクロポリオレフィン樹脂フィルムのＡＲＴＯＮ（日本合成ゴム（株）製）、ポリカーボネートフィルムのピュアエース（帝人（株）製）、セルローストリアセテートフィルムのコニカタックＫＣ４ＵＸ、ＫＣ８ＵＸ（コニカ（株）製）などの市販品を好ましく使用することが出来る。更に、ポリカーボネート、ポリアリレート、ポリスルフォン及びポリエーテルスルフォンなどの固有複屈折率の大きい素材であっても、溶液流延製膜、溶融押し出し製膜等の条件、更には縦、横方向に延伸条件等を適宜設定することにより使用することが出来るものを得ることが出来る。
【０１２３】
これらのうち光学的に等方性に近いセルロースエステルフィルムが本発明に係る光学薄膜に好ましく用いられる。セルロースエステルフィルムとしては、上記のようにセルローストリアセテートフィルム、セルロースアセテートプロピオネートが好ましく用いられるものの一つである。セルローストリアセテートフィルムとしては市販品のコニカタックＫＣ４ＵＸ等が有用である。
【０１２４】
これらの樹脂の表面にゼラチン、ポリビニルアルコール、アクリル樹脂、ポリエステル樹脂、セルロースエステル樹脂等を塗設したものも使用出来る。またこれら樹脂フィルムの薄膜側に防眩層、クリアハードコート層、バリア層、防汚層等を設けてもよい。また、必要に応じて接着層、アルカリバリアコート層、ガスバリア層や耐溶剤性層等を設けてもよい。
【０１２５】
また、本発明に用いられる基材は、上記の記載に限定されない。フィルム形状のものの膜厚としては１０〜１０００μｍが好ましく、より好ましくは４０〜２００μｍである。
【０１２６】
次に、本発明の反射防止フィルムに有用な塗布層について述べる。
本発明の反射防止層またはその他の薄膜は、上記フィルム状またはシート状の基材に直接形成してもよいが、他の層を介してその上に形成してもよい。
【０１２７】
本発明において、基材の薄膜形成側の面に塗布する塗布層（薄膜形成側塗布層）としては、クリアハードコート層、防眩層、接着層、帯電防止層等を挙げることが出来、クリアハードコート層、防眩層、帯電防止層が好ましく塗布され、特に、反射防止フィルムの場合には、クリアハードコート層また防眩フィルム防眩層を反射防止フィルムの表面硬度を高めるために、特に「他の層」として設けることが好ましい。また反射防止層またはその他の薄膜を形成する側と基材の反対側にバックコート層を設けてもよい。
【０１２８】
ここで、本発明に有用な「他の層」としての塗布層として、反射防止フィルムに用いられるクリアハードコート層について述べる。
【０１２９】
クリアハードコート層（防眩層も同じような組成）は、紫外線により硬化する紫外線硬化化合物（樹脂）を含有する層であることが好ましく、耐擦り傷性に優れた反射防止フィルムを得ることが出来る。
【０１３０】
クリアハードコート層の紫外線硬化樹脂層は、エチレン性不飽和モノマーを含む成分を重合させて形成した樹脂層であることが好ましい。ここで、紫外線硬化樹脂層は、紫外線の外に電子線のような活性線照射により架橋反応などを経て硬化する樹脂を主たる成分とする層をいう。紫外線硬化樹脂としては紫外線硬化性樹脂や電子線硬化性樹脂などが代表的なものとして挙げられるが、紫外線や電子線以外の活性線照射によって硬化する樹脂でもよい。紫外線硬化性樹脂としては、例えば、紫外線硬化型アクリルウレタン系樹脂、紫外線硬化型ポリエステルアクリレート系樹脂、紫外線硬化型エポキシアクリレート系樹脂、紫外線硬化型ポリオールアクリレート系樹脂、または紫外線硬化型エポキシ樹脂等を挙げることが出来る。
【０１３１】
紫外線硬化型アクリルウレタン系樹脂は、一般にポリエステルポリオールにイソシアネートモノマー、もしくはプレポリマーを反応させて得られた生成物に更に２−ヒドロキシエチルアクリレート、２−ヒドロキシエチルメタクリレート（以下アクリレートと記載した場合、メタクリレートを包含するものとする）、２−ヒドロキシプロピルアクリレート等の水酸基を有するアクリレート系のモノマーを反応させることによって容易に得ることが出来る（例えば、特開昭５９−１５１１１０号等を参照）。
【０１３２】
紫外線硬化型ポリエステルアクリレート系樹脂は、一般にポリエステルポリオールに２−ヒドロキシエチルアクリレート、２−ヒドロキシアクリレート系のモノマーを反応させることによって容易に得ることが出来る（例えば、特開昭５９−１５１１１２号を参照）。
【０１３３】
紫外線硬化型エポキシアクリレート系樹脂の具体例としては、エポキシアクリレートをオリゴマーとし、これに反応性希釈剤、光反応開始剤を添加し、反応させたものを挙げることが出来る（例えば、特開平１−１０５７３８号）。この光反応開始剤としては、ベンゾイン誘導体、オキシムケトン誘導体、ベンゾフェノン誘導体、チオキサントン誘導体等のうちから、１種もしくは２種以上を選択して使用することが出来る。
【０１３４】
また、紫外線硬化型ポリオールアクリレート系樹脂の具体例としては、トリメチロールプロパントリアクリレート、ジトリメチロールプロパンテトラアクリレート、ペンタエリスリトールトリアクリレート、ペンタエリスリトールテトラアクリレート、ジペンタエリスリトールヘキサアクリレート、アルキル変性ジペンタエリスリトールペンタアクリレート等を挙げることが出来る。
【０１３５】
これらの樹脂は通常公知の光増感剤と共に使用される。また上記光反応開始剤も光増感剤としても使用出来る。具体的には、アセトフェノン、ベンゾフェノン、ヒドロキシベンゾフェノン、ミヒラーズケトン、α−アミロキシムエステル、チオキサントン等及びこれらの誘導体を挙げることが出来る。また、エポキシアクリレート系の光反応剤の使用の際、ｎ−ブチルアミン、トリエチルアミン、トリ−ｎ−ブチルホスフィン等の増感剤を用いることが出来る。塗布乾燥後に揮発する溶媒成分を除いた紫外線硬化性樹脂組成物に含まれる光反応開始剤また光増感剤は該組成物の通常１〜１０質量％添加することが出来、２．５〜６質量％であることが好ましい。
【０１３６】
樹脂モノマーとしては、例えば、不飽和二重結合が一つのモノマーとして、メチルアクリレート、エチルアクリレート、ブチルアクリレート、酢酸ビニル、ベンジルアクリレート、シクロヘキシルアクリレート、スチレン等の一般的なモノマーを挙げることが出来る。また不飽和二重結合を二つ以上持つモノマーとして、エチレングリコールジアクリレート、プロピレングリコールジアクリレート、ジビニルベンゼン、１，４−シクロヘキサンジアクリレート、１，４−シクロヘキシルジメチルアジアクリレート、前出のトリメチロールプロパントリアクリレート、ペンタエリスリトールテトラアクリルエステル等を挙げることが出来る。
【０１３７】
例えば、紫外線硬化樹脂としては、アデカオプトマーＫＲ・ＢＹシリーズ：ＫＲ−４００、ＫＲ−４１０、ＫＲ−５５０、ＫＲ−５６６、ＫＲ−５６７、ＢＹ−３２０Ｂ（以上、旭電化工業株式会社製）、あるいはコーエイハードＡ−１０１−ＫＫ、Ａ−１０１−ＷＳ、Ｃ−３０２、Ｃ−４０１−Ｎ、Ｃ−５０１、Ｍ−１０１、Ｍ−１０２、Ｔ−１０２、Ｄ−１０２、ＮＳ−１０１、ＦＴ−１０２Ｑ８、ＭＡＧ−１−Ｐ２０、ＡＧ−１０６、Ｍ−１０１−Ｃ（以上、広栄化学工業株式会社製）、あるいはセイカビームＰＨＣ２２１０（Ｓ）、ＰＨＣ　Ｘ−９（Ｋ−３）、ＰＨＣ２２１３、ＤＰ−１０、ＤＰ−２０、ＤＰ−３０、Ｐ１０００、Ｐ１１００、Ｐ１２００、Ｐ１３００、Ｐ１４００、Ｐ１５００、Ｐ１６００、ＳＣＲ９００（以上、大日精化工業株式会社製）、あるいはＫＲＭ７０３３、ＫＲＭ７０３９、ＫＲＭ７１３０、ＫＲＭ７１３１、ＵＶＥＣＲＹＬ２９２０１、ＵＶＥＣＲＹＬ２９２０２（以上、ダイセル・ユーシービー株式会社）、あるいはＲＣ−５０１５、ＲＣ−５０１６、ＲＣ−５０２０、ＲＣ−５０３１、ＲＣ−５１００、ＲＣ−５１０２、ＲＣ−５１２０、ＲＣ−５１２２、ＲＣ−５１５２、ＲＣ−５１７１、ＲＣ−５１８０、ＲＣ−５１８１（以上、大日本インキ化学工業株式会社製）、あるいはオーレックスＮｏ．３４０クリヤ（中国塗料株式会社製）、あるいはサンラッドＨ−６０１（三洋化成工業株式会社製）、あるいはＳＰ−１５０９、ＳＰ−１５０７（昭和高分子株式会社製）、あるいはＲＣＣ−１５Ｃ（グレース・ジャパン株式会社製）、アロニックスＭ−６１００、Ｍ−８０３０、Ｍ−８０６０（以上、東亞合成株式会社製）あるいはこの他の市販のものから適宜選択して利用出来る。
【０１３８】
紫外線硬化樹脂層は公知の方法で塗設することが出来る。
紫外線硬化樹脂層を塗設する際の溶媒としては、例えば、炭化水素類、アルコール類、ケトン類、エステル類、グリコールエーテル類、その他の溶媒の中から適宜選択し、あるいはこれらを混合し利用出来る。好ましくは、プロピレングリコールモノ（炭素数１〜４のアルキル基）アルキルエーテル出来はプロピレングリコールモノ（炭素数１〜４のアルキル基）アルキルエーテルエステルを５質量％以上、さらに好ましくは５〜８０質量％以上含有する溶媒が用いられる。
【０１３９】
紫外線硬化性樹脂を光硬化反応により硬化皮膜層を形成するための光源としては、紫外線を発生する光源であれば何れでも使用出来る。例えば、低圧水銀灯、中圧水銀灯、高圧水銀灯、超高圧水銀灯、カーボンアーク灯、メタルハライドランプ、キセノンランプ等を用いることが出来る。照射条件はそれぞれのランプによって異なるが、照射光量は２０〜１００００ｍＪ／ｃｍ^２程度あればよく、好ましくは、５０〜２０００ｍＪ／ｃｍ^２である。近紫外線領域〜可視光線領域にかけてはその領域に吸収極大のある増感剤を用いることによって使用出来る。
【０１４０】
紫外線硬化性樹脂組成物は塗布乾燥された後、紫外線を光源より照射するが、照射時間は０．５秒〜５分がよく、紫外線硬化性樹脂の硬化効率、作業効率とから３秒〜２分がより好ましい。
【０１４１】
こうして得た硬化皮膜層に、ブロッキングを防止するため、また対擦り傷性等を高めるために無機あるいは有機の微粒子を加えることが好ましい。例えば、無機微粒子としては酸化ケイ素、酸化チタン、酸化アルミニウム、酸化錫、酸化亜鉛、炭酸カルシウム、硫酸バリウム、タルク、カオリン、硫酸カルシウム等を挙げることが出来、また有機微粒子としては、ポリメタアクリル酸メチルアクリレート樹脂粉末、アクリルスチレン系樹脂粉末、ポリメチルメタクリレート樹脂粉末、シリコン系樹脂粉末、ポリスチレン系樹脂粉末、ポリカーボネート樹脂粉末、ベンゾグアナミン系樹脂粉末、メラミン系樹脂粉末、ポリオレフィン系樹脂粉末、ポリエステル系樹脂粉末、ポリアミド系樹脂粉末、ポリイミド系樹脂粉末、あるいはポリ弗化エチレン系樹脂粉末等を挙げることが出来、紫外線硬化性樹脂組成物に加えることが出来る。これらの微粒子粉末の平均粒径としては、０．００５μｍ〜１μｍが好ましく０．０１〜０．１μｍであることが特に好ましい。
【０１４２】
紫外線硬化樹脂組成物と微粒子粉末との割合は、樹脂組成物１００質量部に対して、０．１〜１０質量部となるように配合することが望ましい。
【０１４３】
このようにして形成された紫外線硬化樹脂を硬化させた層は、ＪＩＳ　Ｂ　０６０１に規定される中心線平均粗さＲａが１〜５０ｎｍのクリアハードコート層であっても、Ｒａが０．１〜１μｍ程度の防眩層であってもよい。
【０１４４】
クリアハードコート層や防眩層、またはバックコート層を基材に塗布する方法としては、グラビアコーター、スピナーコーター、ワイヤーバーコーター、ロールコーター、リバースコーター、押し出しコーター、エアードクターコーター等公知の方法を用いることが出来る。塗布の際の液膜厚（ウェット膜厚ともいう）で１〜１００μｍ程度で、０．１〜３０μｍが好ましく、より好ましくは、０．５〜１５μｍである。
【０１４５】
【実施例】
以下に、本発明を実施例をもって詳細に説明するが、本発明はこれらに限定されるものではない。
【０１４６】
実施例１
基材として、コニカタックＫＣ８ＵＸフィルム（コニカ（株）製、セルローストリアセテートフィルム）ロールを使用し、アンワインダーに設置した。
【０１４７】
〔バックコート層を有する基材の作製〕
コニカタックＫＣ８ＵＸフィルムの片面に、下記で調製したバックコート層塗布組成物をウェット膜厚１４μｍとなるように押し出しコーターで塗布し、８５℃にて乾燥し巻き取り、バックコート層を有する基材を作製した。
【０１４８】
〈バックコート層塗布組成物の調製〉
アセトン　　　　　　　　　　　　　　　　　　　　　　　　３０質量部
酢酸エチル　　　　　　　　　　　　　　　　　　　　　　　４５質量部
イソプロピルアルコール　　　　　　　　　　　　　　　　　１０質量部
ジアセチルセルロース　　　　　　　　　　　　　　　　　０．６質量部
アエロジル２００Ｖの２％アセトン分散液　　　　　　　　０．２質量部
〔クリアハードコート層を有する基材の作製〕
上記で作製したバックコート層を有する基材のバックコート層と反対側の面上に下記のクリアハードコート層組成物を液膜厚が１３μｍとなるように押し出しコーターで塗布し、次いで８０℃に設定された乾燥部で乾燥した後、１２０ｍＪ／ｃｍ^２で紫外線照射し、乾燥膜厚で３μｍの中心線平均表面粗さ（Ｒａ）１３ｎｍのクリアハードコート層を有する基材を作製し、巻き取った。
【０１４９】
〈クリアハードコート層組成物〉
ジペンタエリスリトールヘキサアクリレート単量体　　　　　６０質量部
ジペンタエリスリトールヘキサアクリレート２量体　　　　　２０質量部
ジペンタエリスリトールヘキサアクリレート３量体以上の成分２０質量部
ジメトキシベンゾフェノン　　　　　　　　　　　　　　　　　４質量部
酢酸エチル　　　　　　　　　　　　　　　　　　　　　　　４５質量部
メチルエチルケトン　　　　　　　　　　　　　　　　　　　４５質量部
イソプロピルアルコール　　　　　　　　　　　　　　　　　６０質量部
〔反射防止フィルムの作製〕
〈大気圧プラズマ放電処理装置と薄膜形成条件〉
《電極の作製》
図２及び３に示したロール電極として、冷却機能を有するチタン合金Ｔ６４製ジャケットロール母材を用い、これにセラミック溶射によりアルミナを１ｍｍ被覆し、その上にテトラメトキシシランを酢酸エチルで希釈した溶液を塗布乾燥後、紫外線照射により硬化させて封孔処理を行いＲｍａｘ１μｍ誘電体を有するロール電極を製作した。一方、図４に示したような中空のチタン合金Ｔ６４製の角型のパイプを用い、上記同様の誘電体を同条件にて被覆して角筒型電極とした。
【０１５０】
《大気圧プラズマ放電処理装置》
図２に示した大気圧プラズマ放電処理装置を、図５のように４基連続して直列に配置した。ロール回転電極２３５、３３５、４３５及び５３５をそれぞれアースに接地し、該ロール回転電極の、その径より大きい円弧上に角筒型固定電極群２３６、３３６、４３６及び５３６を配置し、それぞれの角筒型固定電極群２３６、３３６、４３６及び５３６を電圧印加手段２４０、３４０、４４０及び５４０の高周波電源としてパール工業製高周波電源１３．５６ＭＨｚに接続した。第１の中屈折率層形成用プラズマ放電処理装置２００、第２の高屈折率層形成用プラズマ放電処理装置３００、第３の低屈折率層形成用プラズマ放電処理装置４００、更に第４の防汚層形成用プラズマ放電処理装置５００を４連のプラズマ放電処理装置を直列に配置した。また、中屈折率層形成用、高屈折率層形成用及び低屈折率層形成用の各プラズマ放電処理装置の後にこの順に膜厚制御手段２１０、３１０及び４１０を設置し測定、フィードバック、制御を行った。なお、防汚層形成後においては、膜厚制御手段は設置しなかった。
【０１５１】
《薄膜形成条件》
何れもの大気圧プラズマ放電処理装置の放電空間の圧力を１０３ｋＰａとし、下記の各屈折率層用のガスを混合した状態で、該放電処理空間にガス供給装置から供給し、対向電極間隙（放電空間）を１．０ｍｍとし、周波数１３．５６ＭＨｚの高周波電圧をかけ、１５Ｗ／ｃｍ^２の電力密度を供給した。
【０１５２】
〈中屈折率層を有する基材の作製〉
上記で得たクリアハードコート層とバックコート層を有する基材のクリアハードコート層の上に、最初の中屈折率層形成用プラズマ放電処理装置で、最初に与えた目標値条件に設定し下記中屈折率層用薄膜形成ガスにより、中屈折率層を形成し、中屈折率層を有する基材を中屈折率層側から測定ヘッダー（プローブ）２１４で、設定した４００ｎｍ、４５０ｎｍ、６００ｎｍ、７３０ｎｍ及び７８０ｎｍの各波長において反射率を測定し、各測定値を演算処理装置２１６に送り、目標値との差を演算して、その結果を中屈折率層の膜厚制御系２１７に送り、高周波印加電圧を変化させて膜厚を修正した。その結果、目標値になっていたので、同様の条件で薄膜形成を続け、目標値の中屈折率層を有する基材を得た。なお、全長薄膜形成中も測定、演算、フィードバック及び制御は常に行うようにした。なお、クリアハードコート層については表現を省略して中屈折率層を有する基材とした。
【０１５３】
《中屈折率用ガス》
放電ガス：アルゴン　　　　　　　　　　　　　　　　　９８．７体積％
中屈折率層用薄膜形成ガス：テトラブチル錫蒸気　　　　　０．３体積％
補助ガス：水素ガス　　　　　　　　　　　　　　　　　　　　１体積％
〈中屈折率層／高屈折率層を有する基材〉
続いて、上記で得られた目標値を有する中屈折率層の上に、最初に与えた目標値条件に設定し下記高屈折率層用薄膜形成ガスにより、高屈折率層を形成し、高屈折率層を有する基材を高屈折率層側から測定ヘッダー（プローブ）３１４で、設定した４００ｎｍ、４５０ｎｍ、６００ｎｍ、７３０ｎｍ及び７８０ｎｍの各波長において反射率を測定し、各測定値を演算処理装置３１６に送り、目標値との差を演算して、その結果を高屈折率層の膜厚制御系３１７に送り、高周波印加電圧を変化させて膜厚を修正した。その結果、目標値になっていたので、同様の条件で薄膜形成を続け、目標値の中屈折率層／高屈折率層を有する基材を得た。なお、全長薄膜形成中も測定、演算、フィードバック及び制御は常に行うようにした。なお、基材の上にクリアハードコート層、その上に中屈折率層、更にその上に高屈折率層が積層している様を中屈折率層／高屈折率層のように表した。
【０１５４】

続いて、上記で得られた目標値を有する高屈折率層の上に、最初に与えた目標値条件に設定し下記低屈折率層用薄膜形成ガスにより、低屈折率層を形成し、低屈折率層を有する基材を低屈折率層側から測定ヘッダー（プローブ）４１４で、設定した４００ｎｍ、４５０ｎｍ、６００ｎｍ、７３０ｎｍ及び７８０ｎｍの各波長において反射率を測定し、各測定値を演算処理装置４１６に送り、目標値との差を演算して、その結果を低屈折率層の膜厚制御系４１７に送り、高周波印加電圧を変化させて膜厚を修正した。その結果、目標値になっていたので、同様の条件で薄膜形成を続け、目標値の中屈折率層、高屈折率層及び低屈折率層を有する基材（中屈折率層／高屈折率層／低屈折率層を有する基材）を得た。なお、全長薄膜形成中も測定、演算、フィードバック及び制御は常に行うようにした。
【０１５５】
〈低屈折率用ガス〉
放電ガス：アルゴン　　　　　　　　　　　　　　　　　９８．７体積％
低屈折率層用薄膜形成ガス：テトラエトキシシラン蒸気　　０．３体積％
補助ガス：水素ガス　　　　　　　　　　　　　　　　　　　　１体積％
〈反射防止フィルムの作製〉
上記、中屈折率層／高屈折率層／低屈折率層を有する基材の、低屈折率層の上に、汚れ防止の防汚層を、第４の防汚層形成用プラズマ放電処理装置で、下記防汚層用薄膜形成ガスを用いて形成し、反射防止フィルムを作製した。なお、ここでは膜厚制御は行わなかった。
【０１５６】

なお、中屈折率層の酸化錫層の屈折率：１．７、膜厚：６７ｎｍ、高屈折率層の酸化チタン層の屈折率：２．１４、膜厚：１１０ｎｍ、低屈折率層の酸化珪素層の屈折率：１．４４、膜厚：８７ｎｍ、また防汚層のフッ化珪素層の膜厚：１．２ｎｍとして４層の積層の反射防止フィルムが得られた。
【０１５７】
比較例１
最初に設定条件を目標値条件としただけで、それぞれの高周波印加電圧の制御を一切行わずに薄膜形成を最後まで続行して３層積層し、更に各層形成において、反射率測定器の測定ヘッダー（プローブ）による反射率の測定、演算、フィードバック及び制御を行わなかった以外は実施例１と同様に行い、中屈折率層／高屈折率層／低屈折率層積層を有する反射防止フィルムを得た。
【０１５８】
比較例２
各中屈折率用ガスのうちの中屈折率層用薄膜形成ガス、高屈折率用ガスのうちの高屈折率層用薄膜形成ガス及び低屈折率用ガスのうちの低屈折率層用薄膜形成ガスとしてのそれぞれの有機金属化合物を５質量％低めにし、更に各層形成において、反射率測定器の測定ヘッダー（プローブ）による反射率の測定、演算、フィードバック及び制御を行わなかった以外は実施例１と同様に行い、中屈折率層／高屈折率層／低屈折率層積層を有する反射防止フィルムを得た。
【０１５９】
比較例３
各中屈折率用ガスのうちの中屈折率層用薄膜形成ガス、高屈折率用ガスのうちの高屈折率層用薄膜形成ガス及び低屈折率用ガスのうちの低屈折率層用薄膜形成ガスとしてのそれぞれ有機金属化合物を５質量％高めにし、更に各層形成において、反射率測定器の測定ヘッダー（プローブ）による反射率の測定、演算、フィードバック及び制御を行わなかった以外は実施例１と同様に行い、中屈折率層／高屈折率層／低屈折率層積層を有する反射防止フィルムを得た。
【０１６０】
〔評価〕
〈反射率の目標値との差〉
それぞれ得られた長尺の反射防止フィルムから１００ｍごとに幅方向に５点ずつサンプルを採取し、これら７５個の反射率を、大塚電子（株）製膜厚測定システムＭＣＰＤで測定した。７５個のサンプルの反射率の平均値と、目標値との差を求めた。
【０１６１】
〈着色〉
上記と同様に各７５個のサンプルに付き、着色があるかどうか調べ、下記のレベルで評価した。
【０１６２】
Ａ：色ほとんどなし
Ｂ：僅かに色がある
Ｃ：かなり色がある
Ｄ：色があり、ムラになっている。
【０１６３】
実施例１及び比較例１〜３について、評価した結果を表４に示した。
【０１６４】
【表４】

【０１６５】
（結果）
表４からわかるように、本発明は反射率がほぼ目標値通りで、着色はほとんど認識出来ず、優れた反射防止フィルムを得ることが出来た。これに対し、比較例は、反射率が目標値よりかなり乖離した反射防止フィルムであり、着色もはっきり認識出来た。
【０１６６】
実施例２
実施例１で得られた中屈折率層／高屈折率層積層を有する基材の高屈折率層の上に、第３の低屈折率層形成用プラズマ放電処理装置で、最初に設定した目標値条件で下記低屈折率用ガスにより、低屈折率層を形成した。中屈折率層／高屈折率層／低屈折率層積層を有する基材の低屈折率層側から測定ヘッダー（プローブ）３４で可視光領域全域の反射スペクトルの測定を行い、前述の色差の式に変換した値を、測定値を演算処理装置に送り、目標値との差を演算して、その結果を低屈折率層の膜厚制御系に送り、低屈折率層の形成を続け、再び測定し、目標値になっていたので、その条件で薄膜形成を行い、更に第４の防汚層形成用プラズマ放電処理装置を用いて防汚層を低屈折率層の上に積層し、目標値の中屈折率層／高屈折率層／低屈折率層積層を有する反射防止フィルムを得た。なお、全長薄膜形成中も測定、演算、フィードバック及び制御は常に行うようにした。
【０１６７】
比較例４
実施例１で得られた中屈折率層／高屈折率層積層を有する基材の高屈折率層の上に、最初に設定条件を目標値条件としただけで、低屈折率層を形成し、反射率測定器の測定ヘッダー（プローブ）による可視光領域反射スペクトルを全長について測定を行い、反射スペクトルは色差の式に変換してそのデータをアウトプットしたが、演算、フィードバック予備制御は行わなかった以外は実施例２と同様に行った。
【０１６８】
比較例５
実施例１で得られた中屈折率層／高屈折率層積層を有する基材の高屈折率層の上に、最初に与えた設定条件としただけで、また低屈折率用ガスのうちの低屈折率層用薄膜形成ガスとしてのそれぞれの有機金属化合物を３質量％低めにし、中屈折率層／高屈折率層／低屈折率層積層を有する反射防止フィルムを得、反射率測定器の測定ヘッダー（プローブ）による可視光領域反射スペクトルを全長について測定を行い、反射スペクトルは色差の式に変換してそのデータをアウトプットしたが、演算、フィードバック予備制御は行わなかった以外は実施例２と同様に行った。
【０１６９】
比較例６
実施例１で得られた中屈折率層／高屈折率層積層を有する基材の高屈折率層の上に、最初に与えた設定条件としただけで、また低屈折率用ガスのうちの低屈折率層用薄膜形成ガスとしてのそれぞれの有機金属化合物を３質量％高めにし、中屈折率層／高屈折率層／低屈折率層積層を有する反射防止フィルムを得、反射率測定器の測定ヘッダー（プローブ）による可視光領域反射スペクトルを全長について測定を行い、反射スペクトルは色差の式に変換してそのデータをアウトプットしたが、演算、フィードバック予備制御は行わなかった以外は実施例２と同様に行った。
【０１７０】
実施例２及び比較例４〜６の反射防止フィルムの色について、下記の方法で評価した。その結果を表５に示した。
【０１７１】
〔評価〕
〈ΔＥ^＊ａｂ〉
前述の色差の式のΔＥ^＊ａｂの値を下記のレベルで表した。
【０１７２】
Ａ：０以上、０．５未満（全く異ならないか極めて僅かに異なる）
Ｂ：０．５以上、１．５未満（僅かに異なる）
Ｃ：１．５以上、３．０未満（感知し得る程異なる）
Ｄ：３．０以上、６．０未満（著しく異なる）
Ｅ：６．０以上（極めて著しく異なる）
【０１７３】
【表５】

【０１７４】
（結果）
可視光領域の反射スペクトルを色差の式に変換して着色を膜厚制御系にフィードバックして制御した実施例２では、この方法によっても着色をほとんどなくすことが出来ることがわかった。これに対して、比較例４〜６では、上記と同様なフィードバック及び制御を行わなかったので、着色が目立った。
【０１７５】
【発明の効果】
本発明により、反射がほとんどなくまた、反射で見える色もほとんどない反射防止フィルムを提供出来る。
【図面の簡単な説明】
【図１】反射防止フィルム（基材／中屈折率層／高屈折率層／低屈折率層積層）の可視光波長領域の反射スペクトルを示す図である。
【図２】本発明に係る大気圧プラズマ放電薄膜形成装置の一例を示す概略図である。
【図３】図２に示したロール回転電極の導電性の金属質母材とその上に被覆されている誘電体の構造を示す一例を示す斜視図である。
【図４】図２に示した角筒型電極の母材とその上に被覆されている誘電体の構造を示す一例を示す斜視図である。
【図５】図２の大気圧プラズマ放電処理装置を４連直列に設置した連続して薄膜を積層する大気圧プラズマ放電処理装置の一例を示す図である。
【符号の説明】
２００　中屈折率層形成用プラズマ放電処理装置
２１０、３１０、４１０　膜厚制御手段
２３５、３３５、４３５　ロール回転電極
２３６、３３６、４３６　角筒型固定電極群
２４０、３４０、４４０　電圧印加手段
３００　高屈折率層形成用プラズマ放電処理装置
４００　低屈折率層形成用プラズマ放電処理装置[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for forming an optical thin film useful for a solar cell, a liquid crystal image display device, various display devices, an organic EL display, a CRT, a PDP, and the like, a method for manufacturing an antireflection film, and an antireflection film.
[0002]
[Prior art]
In recent years, a number of anti-reflection techniques have been proposed for screens of image display devices such as CRTs, PDPs, organic EL displays, and liquid crystal image display devices in order to improve the transmittance and contrast and reduce surface reflection in order to reduce glare. It is coming. As an antireflection technique, it is effective to reduce the reflection of light at the interface between the laminate and air by setting the refractive index and the optical thickness of the layer to be laminated as an antireflection layer (also referred to as an optical interference layer) to appropriate values. It is known that
[0003]
In such a multilayer antireflection layer, TiO is used as a material for the high refractive index layer.₂, ZrO₂, Ta₂O₅Etc. and SiO as a material of the low refractive index layer₂, MgF₂These are produced by a dry film forming method using a vacuum such as a sputtering method, a vacuum evaporation method, an ion plating method, and a CVD method. However, such a vacuum apparatus requires a very large film forming apparatus when the area of the processing base material is large, so that the apparatus becomes very expensive, and it is enormous to vacuum or exhaust. Time is spent and productivity is not improved.
[0004]
Further, there is a coating method as another method for producing the antireflection layer. Although this method is useful in terms of high productivity, it has a problem that it is somewhat difficult to maintain the uniformity of the film thickness. Have equally difficult problems.
[0005]
As a countermeasure in this dry film forming method, a film thickness control method using reflected light on a formed substrate while continuously forming a film by atmospheric pressure plasma discharge treatment has been proposed (for example, Patent Document 1). 1). This method uses an on-line film thickness system to irradiate the surface of the formed substrate with light to split the reflected light, detect the spectrum with an optical multi-channel analyzer, and calculate the thin film thickness based on this output. The film thickness is calculated by a dedicated program for performing the above. Further, it is possible to control the film thickness by feeding back a difference from a preset film thickness to a film formation control system. By measuring and inputting the optical constants and thicknesses of the lower layers, and the optical constants of the thin film layers to be formed, in advance, the multi-layered film is also measured. It is stated that the film thickness can also be calculated.
[0006]
However, in the above method, the true film thickness may not be measured in the case of a laminated optical thin film such as an anti-reflection layer. The data of the lower layer in the case where the layers are stacked may be different from the measured value in the case where the layers are actually stacked, and it is difficult to obtain an accurate measurement result. It is also possible to store and input the data from the lower layer according to the position of the base material and calculate it.However, not only does the control system need a huge memory, but it is also necessary to read and calculate the data corresponding to the measurement position. And a complicated operation is required.
[0007]
Further, the thickness of the antireflection layer is such that each layer is a thin film of several tens to several hundreds of nm. If it changes, the reflectivity shifts, and the reflection spectrum reflected from the surface changes, which results in coloring or a change in tint. Further, the yield of the finished film is also deteriorated by setting the conditions.
[0008]
[Patent Document 1]
JP 2001-181850 A
[0009]
[Problems to be solved by the invention]
In addition to the above-described dry film forming method using vacuum such as sputtering method, vacuum evaporation method, ion plating method, and CVD method and wet film forming method by coating, atmospheric pressure plasma CVD method has recently been put into practical use. I have. This atmospheric pressure plasma CVD method has few disadvantages as described above, is easy to use, has excellent productivity, can reduce the cost, and is attracting attention as a future technology.
[0010]
When two or more layers having different refractive indices, such as a low refractive index layer, a medium refractive index layer, and a high refractive index layer, such as an anti-reflection film, are formed, when the film thickness is different, not only the reflection degree is different, but also interference is caused. As a result, coloring of the antireflection layer and a change in tint occur. For example, when the reflection increases, the surrounding light source or a bright object appears on the screen when using a monitor of a television, a personal computer, a car navigation system, or the like, and the display contents are difficult to see. Coloring and different shades not only make it difficult to see, but also cause the image to be noticeably dropped on the TV screen because such a thing appears in the black display area when it appears in the color. It becomes.
[0011]
However, in the case of an optical thin film of the target thickness, especially the antireflection layer obtained by laminating thin films, the thin film is formed by thinking and error of measuring each of them and determining the next condition. That is the current situation.
[0012]
The present invention has been made in view of the above problems, and an object of the present invention is to provide a method for forming an optical thin film having excellent film thickness accuracy by an atmospheric pressure plasma discharge treatment method, and in particular, a reflection method having an antireflection layer. A second object of the present invention is to provide a method for producing an anti-reflection film, and to provide an anti-reflection film having almost no reflection and almost no coloring visible by reflection.
[0013]
[Means for Solving the Problems]
The present invention has the following configuration.
[0014]
(1) In a method of forming an optical thin film on a substrate directly or through another layer under discharge pressure at or near atmospheric pressure by discharge plasma, after forming the optical thin film on the substrate, The reflectance of two or more wavelengths set in the visible light wavelength region of the thin film is measured by an on-line reflectance measuring device, and the standard reflectances determined in advance at the two or more wavelengths and the measured reflectance are measured. A method for forming an optical thin film, comprising comparing and calculating the ratio, feeding back the result to a film thickness control system, and controlling the film thickness of the optical thin film.
[0015]
(2) In a method of forming an optical thin film by discharge plasma directly or through another layer on a substrate to be continuously transferred under atmospheric pressure or a pressure close thereto, the optical thin film is formed on the substrate. After the formation, the reflectance of two or more wavelengths set in the visible light wavelength region of the optical thin film is measured by an on-line reflectance measurement device, and the predetermined standard reflectance and the predetermined reflectance at the two or more wavelengths are measured. A method of comparing the calculated reflectance with the calculated reflectance, feeding the result back to a film thickness control system, and controlling the thickness of the optical thin film.
[0016]
(3) In the method for producing an antireflection film in which an antireflection layer is formed by discharge plasma under atmospheric pressure or a pressure in the vicinity thereof, directly or via another layer, on a substrate to be continuously transferred, After forming the anti-reflection layer thereon, reflectivity of two or more wavelengths set in the visible light wavelength region of the anti-reflection layer is measured by an on-line reflectometer, and at two or more wavelengths, Each of the predetermined standard reflectance and the measured reflectance are compared and calculated, and the result is fed back to a film thickness control system to control the film thickness of the antireflection layer. Production method.
[0017]
(4) In the method for producing an antireflection film, in which each antireflection layer is formed by discharge plasma under atmospheric pressure or a pressure close thereto, directly or via another layer, on a substrate to be continuously transferred, After sequentially forming two or more adjacent anti-reflection layers having different refractive indices on a material, reflection of two or more wavelengths set in the visible light wavelength region with respect to the laminated anti-reflection layer after each anti-reflection layer is formed The reflectance is measured by an on-line reflectance measuring instrument, and the standard reflectances determined in advance at the two or more wavelengths are compared with the measured reflectances and calculated. A method for producing an antireflection film, comprising feeding back to a system and controlling the thickness of each antireflection layer.
[0018]
(5) In the method for producing an antireflection film, in which an antireflection film is formed by discharge plasma under atmospheric pressure or a pressure near the atmospheric pressure directly or through another layer on a substrate to be continuously transferred, After the anti-reflection layer is formed thereon, the reflectivity of one or more wavelengths set in each of two wavelength ranges of 380 to 550 nm and 600 to 800 nm is determined for the anti-reflection layer by using the online reflectivity. Measured by a measuring device, the standard reflectance predetermined at the one or more wavelengths and the measured reflectance are compared and calculated, the result is fed back to a film thickness control system, and the film thickness of the antireflection layer is measured. And a method for producing an antireflection film.
[0019]
(6) In the method for producing an antireflection film, in which an antireflection film is formed by discharge plasma at atmospheric pressure or a pressure close thereto, directly or through another layer, on a substrate to be continuously transferred, After sequentially forming two or more adjacent antireflection layers having different refractive indices thereon, the laminated antireflection layers after the formation of each antireflection layer have a wavelength range of 380 to 550 nm and 600 to 800 nm. The reflectance of one or more set wavelengths is measured by an on-line reflectance measuring device, and each of the predetermined standard reflectances at the one or more wavelengths is compared with the measured reflectance, and the calculated reflectance is calculated. A method for producing an antireflection film, wherein the result is fed back to a film thickness control system each time the antireflection layer is formed, and the film thickness of each antireflection layer is controlled.
[0020]
(7) In the method for producing an antireflection film, in which an antireflection film is formed by discharge plasma at atmospheric pressure or a pressure close thereto, directly or through another layer, on a substrate to be continuously transferred, Is formed on the uppermost layer, the reflection spectrum of the uppermost layer is measured by an on-line reflectometer, and L is calculated from the measured reflection spectrum.^*a^*b^*The color difference or tristimulus value (X, Y, Z) from the color space is obtained, and L from a predetermined standard reflection spectrum is calculated.^*a^*b^*From the color difference or tristimulus values (X, Y, Z) from the color space and the reflection spectrum obtained by measurement, L^*a^*b^*The color difference from the color space or the tristimulus values (X, Y, Z) are compared and calculated, and the result is fed back to the uppermost layer thickness control system to control the formation condition of the uppermost antireflection layer. A method for producing an anti-reflection film.
[0021]
(8) (3) On the base material, three layers are sequentially stacked from the base material side in the order of a medium refractive index layer, a high refractive index layer, and a low refractive index layer (4), (6) or (7). The method for producing an antireflection film according to (1).
[0022]
(9) An anti-reflection film manufactured by the method for manufacturing an anti-reflection film according to any one of (3) to (8).
[0023]
The present invention will be described in detail.
In the present invention, the optical thin film refers to a transparent conductive film, an electrochromic film, a fluorescent film, a solar cell film, a selective absorption film, a selective transmission film, an antireflection film, a shadow mask, a reflection film, and the like as described later. Means a thin film for optical use.
[0024]
In the present invention, the terms anti-reflection film and anti-reflection layer are synonymous with the term low-reflection film or low-reflection layer used elsewhere, but the present invention uses the anti-reflection film and the anti-reflection layer. .
[0025]
The antireflection layer of the antireflection film of the present invention can be obtained by laminating two or more layers having different refractive indices, that is, a high refractive index layer, a medium refractive index layer, and a low refractive index layer. In the present invention, it is preferable that the medium refractive index layer, the high refractive index layer, and the low refractive index layer are laminated on the substrate in this order, but two or more layers having the same refractive index may be laminated. The total number of layers may be six to nine. For example, there may be two or more middle refractive index layers, and layers having different refractive indices may be laminated without being particular about the above order. In the present invention, a triple-layer antireflection film, which is laminated in the order of a middle refractive index layer, a high refractive index layer, and a low refractive index layer from the substrate side, will be described as a representative.
[0026]
The antireflection film of the present invention comprises a medium refractive index layer, a high refractive index layer, and a low refractive index layer, each of which is formed by an atmospheric pressure plasma discharge treatment method in an atmospheric pressure plasma discharge treatment apparatus using each refractive index layer forming gas. These are sequentially laminated on a material.
[0027]
Further, the present invention measures the reflectance in the production line (on-line) of the antireflection film by the atmospheric pressure plasma discharge treatment method, and compares the standard reflectance at a predetermined wavelength with the measured film thickness. This is a method for producing an antireflection film having a target film thickness and refractive index by feeding back the result to a film thickness control system.
[0028]
A method for controlling the film thickness to a target in the present invention will be described.
First, by changing various discharge conditions when the medium refractive index layer is formed by the atmospheric pressure plasma discharge treatment, the film thickness is varied within approximately ± 10% from the sample of the target value of the finished film thickness and the target value. Each sample is prepared, and the reflection spectrum is measured for each of them in the visible light wavelength region of 380 to 800 nm using an on-line reflectometer. At this time, since the reflection spectrum has a fine jagged curve due to the influence of interference, each reflection spectrum approximation curve excluding the influence of interference is obtained as a basic spectrum.
[0029]
The standard reflection spectrum of two or more points (actually, two points) determined in the visible light wavelength region of the sample having the target film thickness of the medium refractive index layer, and the standard reflection spectrum of the sample whose film thickness is varied within ± 10%. Two or more fluctuating reflection spectra are measured using a reflectance measuring device, and are used as standard thickness standard data. These spectral data are input to a computer. In the actual measurement of the reflectance of the medium refractive index layer, only the reflectance of two or more wavelengths determined in the visible light wavelength range may be measured, and the reflectance data of the two or more measurement points may be used. By calculating and comparing the reflectance of the basic data corresponding to the two or more wavelengths of the standard and feeding back to the film thickness control system, and controlling the plasma discharge conditions of the film thickness control system, the film of the target value is obtained. A medium refractive index layer having a thickness and a refractive index is obtained.
[0030]
Next, the measurement of the reflectivity and the control of the film thickness of a high refractive index layer (hereinafter, sometimes referred to as a “medium refractive index layer / high refractive index layer laminate”) layered on the middle refractive index layer will be described.
[0031]
As described above, by changing various discharge conditions when forming by atmospheric pressure plasma discharge treatment on the medium refractive index layer already having the target value, the target value of the finished film thickness is obtained. The reflection spectrum of the middle refractive index layer / high refractive index layer stack is measured in the visible light wavelength region of 380 to 800 nm for the sample and the sample in which the finished film thickness is changed by approximately ± 10% from the target value. At this time, the reflection spectrum is also a finely jagged curve due to the influence of interference. Therefore, the respective reflection spectrum approximation curves excluding the influence of interference are obtained, and the respective curves are converted to a medium refractive index layer / high refractive index. The reflection spectrum of the stack of rate layers is used as basic data. These spectral data are input to a computer. In the actual measurement of the middle refractive index layer / high refractive index layer stack, only the reflectance at two or more points (actually, two points) set within the visible light wavelength region is measured in the same manner as described above. The reflectivity data at this measurement point may be compared with the reflectivity of the basic data corresponding to the wavelengths at the two or more set points and calculated, fed back to the film thickness control system, and the plasma discharge of the film thickness control system may be performed. By controlling the conditions, a middle refractive index layer / high refractive index layer stack having a target thickness and refractive index can be obtained.
[0032]
Furthermore, by changing the various discharge conditions when forming by atmospheric pressure plasma discharge treatment on the high refractive index layer of the middle refractive index layer / high refractive index layer stack already having the target value, For a sample having a target value as the finished film thickness and a sample having the finished film thickness changed by approximately ± 10% from the target value, a middle refractive index layer / high refractive index layer / low refractive index layer laminate in a visible light wavelength region of 380 to 800 nm. Is measured. At this time, the reflection spectrum is also a fine jagged curve due to the influence of interference. Therefore, each reflection spectrum approximation curve excluding the influence of interference is obtained, and the curves are converted into a medium refractive index layer / high refractive index layer. The basic reflection spectrum of the layer / low-refractive-index layer stack and the reflection spectrum of the middle-refractive-index layer / high-refractive-index layer / low-refractive-index layer stack varied within ± 10%. In the actual middle-refractive-index layer / high-refractive-index layer / low-refractive-index layer stack, only the reflectance at two or more (actually, two) wavelengths set in the visible light wavelength region in the same manner as described above. Is calculated by comparing the reflectance data of this measurement point with the reflectance of the set basic data corresponding to the two or more wavelengths, and feeds it back to the film thickness control system. By controlling the plasma discharge conditions described above, an antireflection film of a middle refractive index layer / high refractive index layer / low refractive index layer laminate having a target value of the film thickness and refractive index can be obtained.
[0033]
FIG. 1 is a view showing a reflection spectrum in a visible light wavelength region of an antireflection film (base material / medium refractive index layer / high refractive index layer / low refractive index layer laminate). The vertical axis represents the reflectance and the horizontal axis represents the measurement wavelength, and the reflection spectrum is shown by a curve excluding the influence of interference.
[0034]
Another embodiment of the present invention is a method for controlling the degree of coloring of the finished antireflection film, and the thickness can also be controlled by this method. As shown in FIG. 1, the reflection spectrum of the above-mentioned basic data shows that the reflection spectrum of the middle refractive index layer / high refractive index layer / low refractive index layer stack has a reflectance in two wavelength regions of 380 to 550 nm and 600 to 800 nm. It can be seen that they rise as the wavelength goes to the lower wavelength and the higher wavelength, respectively. This rise causes the color of the anti-reflection film to form. Therefore, by controlling the reflectance (film thickness) in these two wavelength regions, the degree of coloring can be changed, and the coloring can be made inconspicuous in practice.
[0035]
The above basic data also includes data on the increase in the reflectance. Although not shown, the change in the reflection spectrum when the film thickness varies by ± 10% may vary depending on the material used, the number of layers, and the like. In the case of a three-layered rate layer, when the reflection spectrum is 550 nm or less, the reflectance increases when the variation in the film thickness increases to the plus side from the target value, and decreases when the variation in the film thickness increases to the minus side. . On the other hand, when the reflection spectrum is 600 nm or more, the reflectance decreases when the variation of ± 10% of the film thickness increases to the plus side from the target value, and increases when the variation of the film thickness increases to the minus side. Is observed. Such a behavior of the reflection spectrum is large in the case of the middle refractive index layer / high refractive index layer / low refractive index layer laminate, and in the case of the middle refractive index layer single layer or the middle refractive index layer / high refractive index layer laminate. In many cases, the reflection spectrum and behavior of the three-layer stack are different. Therefore, it is necessary to sufficiently observe the spectrum of each of the layers, the laminations, or the materials changed in these regions in advance.
[0036]
The measurement of the reflectance in the visible light wavelength region described above and the measurement of the reflectance for this coloring do not basically change, and the reflection spectrum of the target in the visible light wavelength region of the basic data and the changed one is changed. The same applies to the measurement of the reflectance of a single layer and a laminate. That is, first, the reflectance of the middle refractive index layer, the reflectance of the middle refractive index layer / high refractive index layer stack, and the reflectance of the middle refractive index layer / high refractive index layer / low refractive index layer stack are measured. Calculation, feedback, and control may be similarly performed. However, the difference from the above is that the control in terms of coloring and the measurement of the reflectance are performed at least at one wavelength point in each of the two wavelength regions. The number of measurement points may be any number as long as it is one or more wavelength points, but accurate control is possible if there are at most two points.
[0037]
In the present invention, when each layer is formed by the atmospheric pressure plasma discharge treatment, a command is issued from a computer to a film thickness control system according to the relationship between wavelength, reflectance, and film thickness control described in Tables 1 to 3 below. . However, in the following Tables 1 to 3, it is assumed that the refractive index of each layer is constant. The way of reading this table is that, for example, in Table 3 in which a middle refractive index layer / high refractive index layer / low refractive index layer is formed, a low refractive index layer is formed on the middle refractive index layer / high refractive index layer at 400 nm. When the measured reflectance during formation is lower than the target reflectance (<target reflectance), a command is issued to increase the film thickness during formation because the film thickness is small. At 750 nm, when the measured reflectance when the low refractive index layer is formed on the middle refractive index layer / high refractive index layer is higher than the target reflectance (> target reflectance), the film is formed. Since the thickness is small, a command is issued to increase the thickness of the film being formed. At 550 to 600 nm, the reflectance measured when the low refractive index layer is formed on the middle refractive index layer / high refractive index layer is almost the same as the target reflectance (≒ target reflectance). Since no command for controlling the film thickness can be issued at this wavelength, it is better not to use this region.
[0038]
[Table 1]

[0039]
[Table 2]

[0040]
[Table 3]

[0041]
Further, another aspect of the present invention, which relates to control of coloring, is a method of controlling by converting a total reflection spectrum in a visible light wavelength region into a color difference or tristimulus value. When the low refractive index layer is formed as the uppermost layer of the middle refractive index layer / high refractive index layer / low refractive index layer, the coloring is most conspicuous. Therefore, from the viewpoint of the final finished coloring, the low refractive index layer is also used. Preferably, control is performed during formation. However, it may be difficult to determine which wavelength is involved in coloring. In particular, in the case of finishing by applying the uppermost layer, a slight deviation of the film thickness becomes large at a specific wavelength, and it becomes easy for a person to recognize as a color. L that replaces the color perceived by humans with numerical values^*a^*b^*The color difference is calculated from the following color difference equation (color display method standardized in JIS Z8729) from the color space.
[0042]
ΔE^*ab = [(ΔL^*)²+ (Δa^*)²+ (Δb^*)²]^1/2
Where L^*Is the lightness index, a^*And b^*Is the perceived chromaticity index.
[0043]
Further, the color can be determined based on the tristimulus values (X, Y, Z).
Therefore, in the present invention, a method of obtaining a color by the above-described color difference equation and a method of obtaining a color by tristimulus values (X, Y, Z) are employed as another criterion for determining coloring. This method converts the total reflection spectrum of a target middle refractive index layer / high refractive index layer / low refractive index layer stack into a color difference equation or tristimulus values of X, Y, and Z to obtain low refractive index during thin film formation. The expression of the color difference obtained by converting the total reflection spectrum of the refractive index layer or the tristimulus values of X, Y, and Z is compared with each other, fed back to the low refractive index layer forming film thickness control system, and controlled by the command. .
[0044]
Hereinafter, an atmospheric pressure plasma discharge processing apparatus useful for the present invention will be described, but the present invention is not limited to these apparatuses.
[0045]
FIG. 2 is a schematic view showing an example of an atmospheric pressure plasma discharge thin film forming apparatus according to the present invention. FIG. 2 includes a plasma discharge processing apparatus 30, a gas supply unit 50, a voltage application unit 40, and an electrode temperature adjustment unit 60. The substrate F is subjected to a plasma discharge treatment as a roll rotating electrode 35 and a rectangular cylindrical fixed electrode group 36. In FIG. 1, the roll rotating electrode 35 is a ground electrode, and the rectangular cylindrical fixed electrode group 36 is an application electrode connected to a high frequency power supply 41. The base material F is unwound from an original winding (not shown) and conveyed, or is conveyed from a previous process, and intercepts air or the like that is accompanied by the nip roll 65 through the guide roll 64 and the base material. Then, it is transferred between the rectangular cylindrical fixed electrode group 36 while being wound while being in contact with the roll rotating electrode 35, and is wound up by a winder (not shown) via a nip roll 66 and a guide roll 67. Transfer to the next process. The gas for transparent conductive thin film is supplied by gas supply means 50 by controlling the flow rate of the gas G for transparent conductive thin film (in this case, the discharge gas and the thin film forming gas are mixed) generated by the gas generator 51. The plasma discharge processing vessel 31 is inserted into the plasma discharge processing vessel 31 between the opposing electrodes (this is a discharge space) 32 through the air port 52, and the inside of the plasma discharge processing vessel 31 is filled with the gas G for a transparent conductive thin film, and the discharge processing is performed. The treated exhaust gas G ′ is discharged from the exhaust port 53. Next, the voltage application means 40 applies a voltage to the rectangular cylindrical fixed electrode group 36 by the high frequency power supply 41 to generate a discharge plasma between the electrode and the roll rotating electrode 35 serving as the ground electrode. The medium is heated or cooled by using the electrode temperature control means 60 and the liquid is sent to the roll rotating electrode 35 and the rectangular cylindrical fixed electrode group 36 to the electrode. The temperature of the medium whose temperature has been adjusted by the electrode temperature adjusting means 60 is adjusted from the inside of the roll rotating electrode 35 and the rectangular cylindrical fixed electrode group 36 through the pipe 61 by the liquid sending pump P. During the plasma discharge treatment, the physical properties and composition of the obtained thin film may change depending on the temperature of the base material, and it is preferable to appropriately control this. As the medium, an insulating material such as distilled water or oil is preferably used. At the time of the plasma discharge treatment, it is desirable to control the temperature inside the roll rotating electrode 35 so as to minimize the unevenness of the base material temperature in the width direction or the longitudinal direction. In addition, reference numerals 68 and 69 denote partition plates that partition the plasma discharge processing container 31 from the outside world.
[0046]
FIG. 3 is a perspective view showing an example of a structure of a conductive metal base material of the roll rotating electrode shown in FIG. 2 and a dielectric material coated thereon.
[0047]
In FIG. 3, a dielectric material is coated on the surface side of the roll formed of the conductive metal base material 35A of the roll electrode 35a, and the inside is hollow to form a jacket for temperature control. I have.
[0048]
FIG. 4 is a perspective view showing an example showing the structure of the base material of the rectangular cylindrical electrode shown in FIG. 2 and the dielectric material coated thereon.
[0049]
In FIG. 4, the prismatic electrode 36a has a dielectric coating layer similar to FIG. 3 on a conductive base material such as metal. The square tube-shaped electrode 36a is a hollow metal square pipe, and the surface of the pipe is coated with the same dielectric as described above, so that the temperature can be adjusted during discharge. The number of the square cylindrical fixed electrode groups 36 is plural along the circumference larger than the circumference of the roll rotating electrode 35, and the discharge area is the square cylindrical shape facing the roll rotating electrode 35. This is the entire area of the surface of the mold electrode 36a.
[0050]
The rectangular cylindrical electrode 36a shown in FIG. 4 has an effect of expanding the discharge range (discharge area) as compared with the cylindrical (round) electrode, and is therefore preferably used in the thin film forming method of the present invention.
[0051]
3 and 4, the roll electrode 35a and the prismatic electrode 36a have a structure in which dielectrics 35B and 36B are formed on the surfaces of conductive metallic base materials 35A and 36A. The dielectric coating layer is a ceramic coating layer obtained by spraying ceramics and then performing a sealing treatment using a sealing material of an inorganic compound. The thickness of the ceramic-coated dielectric layer is 1 mm in one piece. Alumina, alumina / silicon nitride, or the like is preferably used as the ceramic material used for thermal spraying. Of these, alumina is more preferably used because it is easy to process.
[0052]
Alternatively, the dielectric layer may be a lining treated dielectric of an inorganic material by glass lining.
[0053]
Examples of the conductive metallic base materials 35A and 36A include metals such as titanium metal or titanium alloy, silver, platinum, stainless steel, aluminum, and iron, and composite materials of iron and ceramics or composite materials of aluminum and ceramics. Titanium metal or a titanium alloy is preferable for the reasons described below.
[0054]
The distance between the opposing electrodes is determined in consideration of the thickness of the dielectric provided on the conductive metal base material, the magnitude of the applied voltage, the purpose of using plasma, and the like. In this case, the shortest distance between the surface of the dielectric and the surface of the conductive metal base material, or the distance between the surfaces of the dielectric when both of the electrodes are provided with a dielectric, uniform discharge in each case. Is preferably 0.5 to 20 mm, particularly preferably 1 ± 0.5 mm.
[0055]
The details of the conductive metallic base material and the dielectric material useful in the present invention will be described later.
[0056]
As the plasma discharge processing container 31, a processing container made of Pyrex (R) glass or the like is preferably used, but a metal container can be used as long as insulation from the electrodes can be obtained. For example, a polyimide resin or the like may be adhered to the inner surface of an aluminum or stainless steel frame, and the metal frame may be sprayed with ceramics to obtain insulation.
[0057]
FIG. 5 is a diagram showing an example of an atmospheric pressure plasma discharge processing apparatus in which the atmospheric pressure plasma discharge processing apparatuses of FIG.
[0058]
A method for manufacturing an antireflection film having a film thickness control means useful in the present invention will be described with reference to FIG. In the present invention, the medium-refractive-index layer is formed on the substrate F unwound from the unwinder (film unwinding machine from a roll) UW by the medium-refractive-index-layer-forming plasma discharge processing apparatus 200, and the formation of the medium-refractive-index layer is performed. When the measurement is completed, the reflectance or the reflection spectrum is detected by the measurement header (probe) 214 of the refractive index measuring device of the film thickness control means 210, and the reflection of two wavelengths in the visible light wavelength region is set by the online reflectance measuring device 215. Measure the rate. The result is calculated by the arithmetic processing unit 216 to calculate the difference from the target value, and is fed back to the medium refractive index layer forming film thickness control system 217 to form the target value medium refractive index layer. The conditions of the application means 240 are checked and the gas supply amount of the gas supply means, the gas concentration of the thin film forming gas, the high frequency applied voltage, the power density, etc. are controlled so as to reach the target value, and the medium refractive index layer having the target value of the film thickness is obtained. To form Here, reference numeral 235 denotes a roll rotating electrode, and 236 denotes a rectangular cylindrical fixed electrode group (here, individual electrodes are omitted).
[0059]
Next, when the formation of the high-refractive-index layer is completed on the medium-refractive-index layer F1 having the target value by the high-refractive-index-layer-forming plasma discharge treatment apparatus 300, the medium-refractive-index layer / high-refractive-index layer stack is formed. From the high refractive index layer side, the reflectance or the reflection spectrum is detected by the measurement header (probe) 314 of the film thickness control means 310, and the reflectance of the two wavelengths in the visible light wavelength region set by the online reflectance measurement device 315. Measure. The result is calculated by the arithmetic processing unit 316 to calculate the difference from the target value, and is fed back to the high refractive index layer forming film thickness control system 317 to form the gas supply means 350 and the voltage so as to form the high refractive index layer having the target value. The conditions of the application means 340 are checked to control the gas supply amount of the gas supply means, the gas concentration of the thin film forming gas, the high frequency applied voltage, the power density, etc. so that the target value is obtained. To form Here, reference numeral 335 denotes a roll rotating electrode, and 336 denotes a prismatic fixed electrode group (here, individual electrodes are omitted).
[0060]
Further, a low-refractive-index layer is formed on the high-refractive-index layer of the medium-refractive-index layer / high-refractive-index layer laminated film F2 having a target film thickness by the plasma discharge treatment apparatus 400 for forming a low-refractive-index layer. Is reflected from the measurement header (probe) 414 of the film thickness control unit 410 from the low refractive index layer side of the reflective film F3 of the triple layer (medium refractive index layer / high refractive index layer / low refractive index layer) at the end of The reflectance or the reflection spectrum is detected, and the reflectance of at least two wavelengths whose visible light wavelength range is set is measured by the online reflectance measuring device 415. The result is calculated by the arithmetic processing unit 416 and fed back to the low-refractive-index-layer-forming-thickness control system 417 to form the low-refractive-index layer with the target value by the gas supply unit 450 and the voltage application unit. The conditions of the means 440 are checked to control the gas supply amount of the gas supply means, the gas concentration of the thin film forming gas, the high frequency applied voltage, the power density, etc. so that the low refractive index layer having the target value is formed. Form. Here, reference numeral 435 is a roll rotating electrode, and 436 is a square cylindrical fixed electrode group (each electrode is omitted here).
[0061]
In addition, the substrate F3 having the middle refractive index layer / high refractive index layer / low refractive index layer stack is coated on the low refractive index layer by the fourth plasma discharge treatment apparatus 500 for forming an antifouling layer. Form a layer. Here, reference numeral 535 denotes a roll rotating electrode, 536 denotes a rectangular cylindrical fixed electrode group (each electrode is omitted here), 550 denotes a gas supply unit, and 540 denotes a high frequency voltage applying unit.
[0062]
The finished antireflection film F4 of the laminated middle refractive index layer / high refractive index layer / low refractive index layer / antifouling layer is wound up by the unwinder W, and the production of the antireflection film of the present invention is completed.
[0063]
It is preferable that the measurement headers (probes) 214, 314, and 414 detect the reflectance while reciprocating in the width direction of the base material.
[0064]
A reflectance measurement method useful in the present invention is a method using a reflectance and a reflection spectrum. For example, a film thickness measurement system MCPD series (combination of an MCPD detector and an optical fiber) manufactured by Otsuka Electronics Co., Ltd. is preferably used. I can do it.
[0065]
In the present invention, it is preferable that the probe for measuring the reflectance of the measurement system be reciprocally movable in the width direction so as to cover the entire length and the entire width of the substrate as much as possible. In the measurement of the present invention, the information of the reflectance and the reflection spectrum of the medium refractive index layer formed first, the information of the reflectance and the reflection spectrum of the next high-refractive-index layer stack, and further the information of the low-refractive-index layer stack The information is fed back at each stage, and is compared with information obtained in advance in a computer to control the target reflectance over the entire width of each layer and stack. By measuring the reflectance and the reflection spectrum at each stage online during the formation of the laminated anti-reflection layer in this way, it is possible to produce an anti-reflection film of excellent quality and to obtain a higher yield. This enables stable production. In addition, by measuring the entire length of the anti-reflective film online using a measuring probe, the quality information can be known from the product information of the rolled long roll, such as defect information over the entire length of the anti-reflection film and information on parts that can be commercialized. Can also provide useful information.
[0066]
Further, in order to feed back more accurate information, the measurement from the plurality of measurement probes is alternately repeated by measuring and moving at least two measurement probes in the width direction at least in the vertical direction. It is preferable to obtain an average value of the data.
[0067]
In the present invention, when measuring reflected light, it is preferable that the inside of the measurement chamber be in a dark state without light, but since the film thickness measurement system can measure the reflectance without having to do so. It doesn't always go dark. The measurement position of the probe in the measurement chamber is preferably measured at a position where the roll interval is small, for example, within a range of 300 mm where the film does not vibrate, but more preferably within a range of approximately 10 mm from the roll. Further, when measuring the reflected light, an accumulator may be provided before and after the base material at the measurement position, and the base material may be temporarily stopped to perform the measurement.
[0068]
Next, the high-frequency power supply, electrodes, and conditions used in the present invention will be described.
The high frequency power supply installed in the atmospheric pressure plasma discharge treatment apparatus useful in the present invention includes a high frequency power supply (100 kHz *) manufactured by Heiden Laboratory, a high frequency power supply (200 kHz) manufactured by Pearl Industries, a high frequency power supply (800 kHz) manufactured by Pearl Industries, and Pearl Industry Commercially available high-frequency power supplies (2 MHz), Pearl Industrial high-frequency power supplies (13.56 MHz), Pearl Industrial high-frequency power supplies (27 MHz), Pearl Industrial high-frequency power supplies (150 MHz), and the like can be used. I can do it. In addition, * mark is a HEIDEN laboratory impulse high frequency power supply (100 kHz in continuous mode).
[0069]
In the present invention, it is necessary to employ an electrode capable of maintaining a uniform glow discharge state by applying such a voltage to the plasma discharge processing apparatus.
[0070]
In the present invention, the power density applied between the opposing electrodes is 1 W / cm²The above power density (output density) is supplied to excite the discharge gas to generate plasma, and apply energy to the thin film forming gas to form a thin film. The upper limit of the supplied power density is preferably 50 W / cm²Or less, more preferably 20 W / cm²It is as follows. The lower limit is preferably 1.2 W / cm²That is all. The discharge area (cm²) Refers to the area of the range in which discharge occurs in the electrode.
[0071]
Regarding the method of applying power, either a continuous sine-wave continuous oscillation mode called a continuous mode or an intermittent oscillation mode in which ON / OFF is intermittently called a pulse mode may be adopted. Is preferred since a denser and higher quality film can be obtained.
[0072]
Electrodes used in such a thin film formation method using atmospheric pressure plasma must be able to withstand severe conditions in terms of structure and performance. Such an electrode is preferably a metal base material coated with a dielectric.
[0073]
In the dielectric-coated electrode used in the present invention, it is preferable that the characteristics match between various metallic base materials and the dielectric. One of the characteristics is the linear thermal expansion between the metallic base material and the dielectric. The coefficient difference is 10 × 10^-6/ ° C or lower. Preferably 8 × 10^-6/ ° C or lower, more preferably 5 × 10^-6/ ° C or lower, more preferably 2 × 10^-6/ ° C or lower. Note that the linear thermal expansion coefficient is a physical property value specific to a known material.
[0074]
The difference between the coefficients of linear thermal expansion is as follows:
(1) The metallic base material is pure titanium or a titanium alloy, and the dielectric is a ceramic sprayed coating.
(2) The metallic base material is pure titanium or a titanium alloy, and the dielectric is glass lining
(3) The metallic base material is stainless steel, and the dielectric is ceramic sprayed coating
4) Metallic base material is stainless steel, dielectric is glass lining
(5) The metallic base material is a composite material of ceramics and iron, and the dielectric is a ceramic sprayed coating.
(6) The metal base material is a composite material of ceramics and iron, and the dielectric is glass lining
(7) The metallic base material is a composite material of ceramics and aluminum, and the dielectric is a ceramic sprayed coating.
(8) The metal base material is a composite material of ceramics and aluminum, and the dielectric is glass lining
Etc. From the viewpoint of the difference in linear thermal expansion coefficient, the above (1) or (2) and (5) to (8) are preferable, and (1) is particularly preferable.
[0075]
In the present invention, titanium or a titanium alloy is particularly useful as the metallic base material from the above characteristics. By using titanium or titanium alloy as the metallic base material, and by setting the dielectric material to the above, there is no deterioration of the electrode during use, especially cracking, peeling, falling off, etc., and it is used for a long time under severe conditions Can withstand.
[0076]
The metallic base material of the electrode useful in the present invention is a titanium alloy or titanium metal containing 70% by mass or more of titanium. In the present invention, the content of titanium in the titanium alloy or titanium metal can be used without any problem as long as it is 70% by mass or more, but preferably contains 80% by mass or more of titanium. As the titanium alloy or titanium metal useful for the present invention, those generally used as industrial pure titanium, corrosion-resistant titanium, high-strength titanium and the like can be used. Examples of industrial pure titanium include TIA, TIB, TIC, TID, etc., all of which contain very little iron, carbon, nitrogen, oxygen, hydrogen, etc. The content is 99% by mass or more. As the corrosion-resistant titanium alloy, T15PB can be preferably used, which contains lead in addition to the above contained atoms, and has a titanium content of 98% by mass or more. In addition, as the titanium alloy, in addition to the above atoms except for lead, T64, T325, T525, TA3, and the like containing aluminum and containing vanadium and tin can be preferably used. The amount is 85% by mass or more. These titanium alloys or titanium metals have a coefficient of thermal expansion smaller than that of stainless steel, for example, AISI316, by about 、, and are combined with a later-described dielectric material provided on the titanium alloy or titanium metal as a metallic base material. It can withstand high temperature and long time use.
[0077]
On the other hand, as the properties required of the dielectric, specifically, an inorganic compound having a relative dielectric constant of preferably 6 to 45 is preferable, and such dielectrics include ceramics such as alumina and silicon nitride; Alternatively, there are glass lining materials such as silicate glass and borate glass. Among these, those obtained by spraying ceramics described later and those provided by glass lining are preferable. In particular, a dielectric provided by spraying alumina is preferable.
[0078]
Alternatively, as one of the specifications that can withstand the large power as described above, the porosity of the dielectric is 10% by volume or less, preferably 8% by volume or less, preferably more than 0% by volume and 5% by volume or less. It is. The porosity of the dielectric can be measured by a BET adsorption method or a mercury porosimeter. In the examples described later, the porosity is measured using a piece of a dielectric material coated on a metallic base material using a mercury porosimeter manufactured by Shimadzu Corporation. High durability is achieved by the dielectric having a low porosity. Examples of the dielectric having such voids and low porosity include a ceramic sprayed coating having a high density and a high adhesion by an atmospheric pressure plasma spraying method described later. In order to further reduce the porosity, it is preferable to perform a sealing treatment.
[0079]
The above atmospheric pressure plasma spraying method is a technique in which fine powders such as ceramics, wires and the like are charged into a plasma heat source and sprayed as fine particles in a molten or semi-molten state onto a metal base material to be coated to form a film. . The plasma heat source is a high-temperature plasma gas in which a molecular gas is heated to a high temperature, dissociated into atoms, and further applied with energy to emit electrons. This plasma gas is sprayed at a high speed, and the sprayed material collides with the metal base material at a higher speed than conventional arc spraying or flame spraying, so that a high adhesion strength and a high-density coating can be obtained. For details, reference can be made to the thermal spraying method for forming a heat shielding film on a high-temperature exposed member described in JP-A-2000-301655. According to this method, the porosity of the dielectric material (ceramic sprayed film) to be coated as described above can be obtained.
[0080]
Another preferable specification that can withstand high power is that the thickness of the dielectric is 0.5 to 2 mm. This variation in film thickness is desirably 5% or less, preferably 3% or less, and more preferably 1% or less.
[0081]
In order to further reduce the porosity of the dielectric, it is preferable that the sprayed film of ceramic or the like is further subjected to sealing treatment with an inorganic compound as described above. As the inorganic compound, metal oxides are preferable, and among them, silicon oxide (SiO 2) is particularly preferable._x) Is preferable.
[0082]
It is preferable that the inorganic compound for the pore-sealing treatment is formed by curing by a sol-gel reaction. In the case where the inorganic compound for the sealing treatment contains a metal oxide as a main component, a metal alkoxide or the like is applied as a sealing liquid on the ceramic sprayed film and cured by a sol-gel reaction. When the inorganic compound is mainly composed of silica, it is preferable to use alkoxysilane as the sealing liquid.
[0083]
Here, it is preferable to use energy treatment to promote the sol-gel reaction. Examples of the energy treatment include thermal curing (preferably 200 ° C. or lower) and ultraviolet irradiation. Further, as a sealing treatment method, when the sealing liquid is diluted and coating and curing are repeated several times sequentially, the mineralization is further improved, and a dense electrode without deterioration can be obtained.
[0084]
When coating the ceramic sprayed film with a metal alkoxide or the like of the dielectric-coated electrode according to the present invention as a sealing liquid, and then performing a sealing treatment of curing by a sol-gel reaction, the content of the cured metal oxide is 60%. It is preferably at least mol%. When alkoxysilane is used as the metal alkoxide of the sealing liquid, the cured SiO 2_x(X is 2 or less) The content is preferably 60 mol% or more. SiO after curing_xThe content is measured by analyzing a fault of the dielectric layer by XPS.
[0085]
In the electrode according to the thin film forming method of the present invention, it is preferable that the maximum height (Rmax) of the surface roughness defined by JIS B0601 at least on the side of the electrode in contact with the base material is controlled to be 10 μm or less. It is preferable from the viewpoint of obtaining the effects described in the present invention, but more preferably, the maximum value of the surface roughness is 8 μm or less, and particularly preferably, it is controlled to 7 μm or less. In this way, the thickness of the dielectric and the gap between the electrodes can be kept constant by the method of polishing and finishing the dielectric surface of the dielectric coated electrode, and the discharge state can be stabilized. Distortion and cracks due to residual stress can be eliminated, and high accuracy and durability can be greatly improved. The polishing finish of the dielectric surface is preferably performed at least on the dielectric in contact with the base material. Further, the center line average surface roughness (Ra) defined by JIS {B} 0601 is preferably 0.5 μm or less, more preferably 0.1 μm or less.
[0086]
Another preferable specification of the dielectric-coated electrode used in the present invention that withstands large power is that the heat-resistant temperature is 100 ° C. or higher. It is more preferably at least 120 ° C, particularly preferably at least 150 ° C. The upper limit is 500 ° C. Note that the heat-resistant temperature refers to the highest temperature that can withstand normal discharge without dielectric breakdown. Such a heat-resistant temperature is within the range of the difference between the linear thermal expansion coefficient of the metal base material and the dielectric material provided by the above-described ceramic spraying or a dielectric provided with a layered glass lining having a different amount of bubbles mixed therein. It can be achieved by appropriately combining means for appropriately selecting the above materials.
[0087]
Next, the gas for forming the thin film of the present invention will be described. The gas to be used is basically a gas containing a discharge gas and a thin film forming gas as constituent components. The discharge gas and the thin film forming gas may be mixed and supplied to the discharge space or the processing space, or may be separately supplied as another embodiment as described above. When separately supplied, the ratio of the discharge gas and the thin film forming gas in the processing space is preferably 100: 1 to 5: 1. This ratio is the field where the thin film is formed on the substrate, ie the discharge space or the processing space. Since the thin film forming gas when separately supplied cannot be supplied to the discharge space or the processing space by the thin film forming gas alone, it is easy to supply by bubbling the thin film forming gas in an inert gas and vaporizing it. . At this time, the inert gas (which may be the same as the discharge gas) is preferably 98.0 to 99.1% by volume, and the thin film forming gas is preferably about 0.9 to 2.0% by volume.
[0088]
The discharge gas is a gas capable of generating a glow discharge capable of forming a thin film, and itself functions as a medium for transferring energy. Examples of the discharge gas include nitrogen, a rare gas, air, hydrogen gas, and oxygen, and these may be used alone as a discharge gas or may be used as a mixture. Examples of the rare gas include elements belonging to Group 18 of the periodic table, specifically, helium, neon, argon, krypton, xenon, and radon. The amount of the discharge gas is preferably 90.0 to 99.9% by volume based on the total amount of gas supplied to the discharge space or the processing space.
[0089]
Next, the discharge processing gas for forming the highly functional thin film of the present invention will be described. The discharge processing gas used is basically a gas composed of a discharge gas and a thin film forming gas.
[0090]
The thin film forming gas receives the energy from the discharge gas in the discharge space, becomes an excited state or a plasma state, and forms a highly functional thin film, or is a gas that controls the reaction or promotes the reaction.
[0091]
In the present invention, the thin film forming gas contains at least an organometallic compound. In some cases, an organometallic compound for doping is added to a metal oxide formed from an organometallic compound, and a similar organometallic compound is used.
[0092]
The organometallic compounds useful in the present invention are preferably those represented by the following general formula (I). General formula (I) R¹ _xMR² _yR³ _z
Where M is a metal, R¹Is an alkyl group, R²Is an alkoxy group, R³Is a group selected from a β-diketone complex group, a β-ketocarboxylic ester complex group, a β-ketocarboxylic acid complex group, and a ketooxy group (ketooxy complex group). And x = 0 to m or x = 0 to m-1, y = 0 to m and z = 0 to m, each of which is 0 or a positive integer. R¹Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, and a butyl group. R²Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, and a 3,3,3-trifluoropropoxy group. Further, a hydrogen atom of an alkyl group may be substituted with a fluorine atom. R³The group selected from the group consisting of β-diketone complex group, β-ketocarboxylic ester complex group, β-ketocarboxylic acid complex group and ketooxy group (ketooxy complex group) includes, for example, 2,4-pentane as a β-diketone complex group. Dione (also called acetylacetone or acetoacetone), 1,1,1,5,5,5-hexamethyl-2,4-pentanedione, 2,2,6,6-tetramethyl-3,5-heptanedione, , 1,1-trifluoro-2,4-pentanedione, and the like. Examples of the β-ketocarboxylic acid ester complex group include, for example, methyl acetoacetate, ethyl acetoacetate, propyl acetoacetate, and trimethylacetoacetate. Ethyl, methyl trifluoroacetoacetate and the like can be mentioned, and as β-ketocarboxylic acid, for example, , Acetoacetic acid, can be mentioned trimethyl acetoacetate, and as Ketookishi, for example, acetoxy group (or an acetoxy group), a propionyloxy group, Buchirirokishi group, acryloyloxy group, methacryloyloxy group and the like. The number of carbon atoms of these groups is preferably 18 or less, including the organometallic compounds described above. As shown in the examples, it may be a straight-chain or branched one, or a hydrogen atom substituted with a fluorine atom.
[0093]
From the viewpoint of handling in the present invention, an organometallic compound having a low risk of explosion is preferred, and an organometallic compound having at least one or more oxygen atoms in the molecule is preferred. As such R²An organometallic compound containing at least one alkoxy group of³And a metal compound having at least one group selected from the group consisting of a β-diketone complex group, a β-ketocarboxylic ester complex group, a β-ketocarboxylic acid complex group, and a ketooxy group (ketooxy complex group).
[0094]
The specific organometallic compound will be described later.
In the present invention, the gas supplied to the discharge space may be mixed with an auxiliary gas (or an additional gas) which promotes a reaction of forming a thin film, in addition to the discharge gas and the thin film forming gas. Examples of the auxiliary gas include oxygen, ozone, hydrogen peroxide, carbon dioxide, carbon monoxide, hydrogen, and ammonia. Oxygen, carbon monoxide and hydrogen are preferable, and components selected from these are mixed. It is preferred that When the content is 0.01 to 5% by volume with respect to the discharge treatment gas, the reaction is promoted, and a dense and high-quality thin film can be formed.
[0095]
The thickness of the formed oxide or composite compound thin film is preferably in the range of 0.1 to 1000 nm.
[0096]
In the present invention, Li, Be, B, Na, Mg, Al, Si, K, Ca are used as the metal of the general formula (I), the metal halide or the metal hydride of the organometallic compound used for the thin film forming gas. , Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Rb, Sr, Y, Zr, Nb, Mo, Cd, In, Ir, Sn, Sb, Cs, Ba , La, Hf, Ta, W, Tl, Pb, Bi, Ce, Pr, Nd, Pm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu and the like.
[0097]
In the method of forming a thin film of the present invention, various highly functional thin films can be obtained by using a metal compound such as the above-mentioned organometallic compound, halogen metal compound, or metal hydride compound together with a discharge gas. Examples of the thin film of the present invention are shown below, but the present invention is not limited thereto.
[0098]
Electrode film Au, Al, Ag, Ti, Ti, Pt, Mo, Mo-Si
Dielectric protection film @ SiO₂, SiO, Si₃N₄, Al₂O₃, Al₂O₃, Y₂O₃
Transparent conductive film @In₂O₃, SnO₂
Electrochromic film @ WO₃, IrO₂, MoO₃, V₂O₅
Phosphor film: ZnS, ZnS + ZnSe, ZnS + CdS
Magnetic recording film @ Fe-Ni, Fe-Si-Al, γ-Fe₂O₃, Co, Fe₃O₄, Cr, SiO₂, AlO₃
Super conductive film Nb, Nb-Ge, NbN
Solar cell membrane a-Si, Si
Reflective film: Ag, Al, Au, Cu
Selective absorption membrane @ ZrC-Zr
Selective permeable membrane @In₂O₃, SnO₂
Anti-reflective coating @ SiO₂, TiO₂, SnO₂, Sn-In₂O₃(ITO), F-SnO₂(FTO), Zn-In₂O₃(IZO)
Shadow mask @ Cr
Abrasion resistant film Cr, Ta, Pt, TiC, TiN
Corrosion resistant film Al, Zn, Cd, Ta, Ti, Cr
Heat resistant film @W, Ta, Ti
Lubrication film MoS₂
Decorative film: Cr, Al, Ag, Au, TiC, Cu
In the present invention, particularly preferred metals of the metal compound are Si (silicon), Ti (titanium), Sn (tin), Zn (zinc), In (indium), and Al (aluminum) among the above. Among the metal compounds that bind to, the organometallic compounds represented by the general formula (I) are preferable. Examples of the organometallic compound will be described later.
[0099]
Here, the antireflection film (layer) and the antireflection film and the transparent conductive film in which the antireflection film is laminated will be described in detail.
[0100]
Among the thin films according to the present invention, the antireflection layer of the antireflection film is formed by laminating thin films of a medium refractive index layer, a high refractive index layer, and a low refractive index layer.
[0101]
The titanium compound forming the high refractive index layer, the tin compound forming the middle refractive index layer, and the silicon compound forming the low refractive index layer of the antireflection layer thin film forming gas according to the present invention will be described. An antireflection film having an antireflection layer is obtained by laminating each refractive index layer directly or via another layer on a substrate. In order to stack three layers of the atmospheric pressure plasma discharge processing apparatus in the order of the medium refractive index layer, the high refractive index layer, and the low refractive index layer, three units can be arranged in series and continuously processed. Is suitable for forming the thin film of the present invention from the viewpoint of stability of quality and improvement of productivity. Instead of laminating, winding may be performed after each layer processing, and the layers may be sequentially processed and laminated. In the present invention, in the case where an antifouling layer is provided on the antireflection layer, another plasma discharge treatment apparatus may be further installed continuously, four antifouling layers may be arranged, and finally the antifouling layer may be laminated. Before providing the anti-reflection layer, a hard coat layer or an anti-glare layer may be provided in advance on the base material by coating, or a back coat layer may be provided in advance on the back side by coating.
[0102]
As the gas for forming the antireflection layer thin film of the antireflection film according to the present invention, any compound capable of obtaining an appropriate refractive index can be used without any limitation. The compound is formed of a mixture of a tin compound or a titanium compound and a silicon compound (or a layer formed of a titanium compound for forming a high refractive index and a layer formed of a silicon compound forming a low refractive index layer as a medium refractive index layer thin film forming gas). And a low-refractive-index layer thin film forming gas, preferably a silicon compound, a fluorine compound, or a mixture of a silicon compound and a fluorine compound. In order to adjust the refractive index of these compounds, two or more thin film forming gases used for any of the layers may be used in combination.
[0103]
The tin compound used for the medium refractive index layer thin film forming gas useful in the present invention is an organic tin compound, a tin hydride compound, a tin halide, and the like. Examples of the organic tin compound include dibutyldiethoxytin and butyltin tris. (2,4-pentanedionate), tetraethoxy tin, methyl triethoxy tin, diethyl diethoxy tin, triisopropyl ethoxy tin, ethyl ethoxy tin, methyl methoxy tin, isopropyl isopropoxy tin, tetrabutoxy tin, diethoxy tin, dimethoxy Tin, diisopropoxy tin, dibutoxy tin, dibutylyloxy tin, diethyl tin, tetrabutyl tin, tin bis (2,4-pentanedionate), ethyl tin acetoacetonate, ethoxy tin (2,4-pentanedionate), dimethyl Tin di (2,4-pentanedionate), diacetmethyl acetate Tin, diacetoxytin, dibutoxydiacetoxytin, diacetoxytin diacetacetonate, and the like, tin hydride and the like, as tin halides, tin dichloride, tin tetrachloride and the like, all of which in the present invention, It can be preferably used. Further, two or more of these thin film forming gases may be mixed and used at the same time. The tin oxide layer thus formed has a surface resistivity of 10¹¹Ω / cm²Since it can be reduced to the following, it is also useful as an antistatic layer.
[0104]
Examples of the titanium compound used for the high refractive index layer thin film forming gas useful in the present invention include an organic titanium compound, a titanium hydride compound, a titanium halide, and the like. Examples of the organic titanium compound include triethoxytitanium and trimethoxytitanium. , Triisopropoxytitanium, tributoxytitanium, tetraethoxytitanium, tetraisopropoxytitanium, methyldimethoxytitanium, ethyltriethoxytitanium, methyltriisopropoxytitanium, triethyltitanium, triisopropyltitanium, tributyltitanium, tetraethyltitanium, tetraisopropyltitanium , Tetrabutyltitanium, tetradimethylaminotitanium, dimethyltitanium di (2,4-pentanedionate), ethyl titanium tri (2,4-pentanedionate), titanium tris (2,4-pentanedionate) ), Titanium tris (acetomethyl acetate), triacetoxytitanium, dipropoxypropionyloxytitanium, etc., dibutylyloxytitanium, titanium hydrogen compounds such as monotitanium hydride compounds, dititanium hydride compounds, etc. Trichlorotitanium, tetrachlorotitanium and the like can be mentioned, and any of them can be preferably used in the present invention. Also, two or more of these thin film forming gases can be mixed and used at the same time.
[0105]
Examples of the silicon compound used in the low-refractive index layer thin film forming gas useful in the present invention include an organic silicon compound, a silicon hydride compound, a silicon halide compound, and the like. As the organic silicon compound, for example, tetraethylsilane, Tetramethylsilane, tetraisopropylsilane, tetrabutylsilane, tetraethoxysilane, tetraisopropoxysilane, tetrabutoxysilane, dimethyldimethoxysilane, diethyldiethoxysilane, diethylsilanedi (2,4-pentanedionate), methyltrimethoxy Silane, methyltriethoxysilane, ethyltriethoxysilane and the like; silicon hydrides such as tetrahydrogenated silane and hexahydrogenated disilane; and silicon halides such as tetrachlorosilane, methyltrichlorosilane and diethyldichlorosilane Can be mentioned silane, both can be preferably used in the present invention. Further, the above-mentioned fluorine compounds can be used. These thin film forming gases can be used by mixing two or more kinds at the same time. For controlling the refractive index, two or more of these tin compounds, titanium compounds and silicon compounds may be appropriately mixed and used at the same time.
[0106]
The above-mentioned organotin compound, organotitanium compound or organosilicon compound is preferably a metal hydrogen compound or an alkoxy metal from the viewpoint of handling, and is not corrosive, generates no harmful gas, and has little contamination in the process. Metals are preferably used. In order to introduce the above-mentioned organotin compound, organotitanium compound or organosilicon compound between electrodes, which are discharge spaces, both may be in a gas, liquid or solid state at normal temperature and normal pressure. In the case of a gas, it can be introduced into the discharge space as it is, but in the case of a liquid or solid, it is used after being vaporized by means such as heating, decompression, or ultrasonic irradiation. When an organotin compound, an organotitanium compound or an organosilicon compound is used after being vaporized by heating, a metal alkoxide having a boiling point of 200 ° C. or less, such as tetraethoxy metal or tetraisopropoxy metal, is liquid at ordinary temperature to form an antireflection film. It is suitably used. The alkoxy metal may be used after being diluted with a solvent. In this case, the alkoxy metal may be vaporized into a rare gas by a vaporizer or the like and used as a mixed gas. As the solvent, organic solvents such as methanol, ethanol, isopropanol, butanol, n-hexane and the like and a mixed solvent thereof can be used.
[0107]
From the viewpoint of forming a uniform thin film on the substrate by the discharge plasma treatment, the content of the gas for forming a thin film is preferably 0.01 to 10% by volume, more preferably 0.1 to 10% by volume. 01 to 1% by volume.
[0108]
The medium refractive index layer can also be obtained by appropriately mixing the silicon compound, the titanium compound or the tin compound according to a target refractive index.
[0109]
The preferable refractive index and thickness of each refractive index layer are, for example, 1.6 to 1.8 as the refractive index and about 50 to 70 nm as the thickness of the tin oxide layer of the middle refractive index layer. The titanium oxide layer has a refractive index of 1.9 to 2.4 and a thickness of about 80 to 120 nm, and the silicon oxide layer of the low refractive index layer has a refractive index of 1.3 to 1.5 and a thickness of 80 to 120 nm. About 120 nm.
[0110]
Next, formation of a thin film having a transparent conductive film will be described as another example of the thin film according to the present invention.
[0111]
Although the metal component of the organometallic compound used in forming the antireflection layer described above slightly differs in that it forms a thin film having transparency and conductivity such as indium, the organic group has almost the same components. Used.
[0112]
A preferred metal of the organometallic compound forming the transparent conductive film is at least one metal selected from indium (In), zinc (Zn) and tin (Sn).
[0113]
In the present invention, preferred examples of preferred organometallic compounds include indium tris (2,4-pentanedionate), indium tris (hexafluoropentanedionate), indium triacetoacetate, triacetoxyindium, diethoxyacetoxyindium, Triisopolopoxyindium, diethoxyindium (1,1,1-trifluoropentanedionate), tris (2,2,6,6-tetramethyl-3,5-heptanedionate) indium, ethoxyindium bis ( Acetomethyl acetate), di (n) butyltin bis (2,4-pentanedionate), di (n) butyldiacetoxytin, di (t) butyldiacetoxytin, tetraisopropoxytin, tetra (i) Butoxy tin, bis (2,4-pentanedionate) It can be mentioned such as lead. These organometallic compounds are generally commercially available (for example, from Tokyo Chemical Industry Co., Ltd.).
[0114]
In the present invention, in addition to the organometallic compound having at least one oxygen atom in the molecule, doping the transparent conductive film to further enhance the conductivity of the transparent conductive film formed from the organometallic compound Preferably, the organometallic compound as a thin film forming gas and the doping organometallic compound gas are mixed and used at the same time. As a thin film forming gas of an organometallic compound or a fluorine compound used for doping, for example, triisopropoxyaluminum, tris (2,4-pentanedionate) nickel, bis (2,4-pentanedionate) manganese, isopropoxy boron
, Tri (n) butoxyantimony, tri (n) butylantimony, di (n) butylbis (2,4-pentanedionate) tin, di (n) butyldiacetoxytin, di (t) butyldiacetoxytin, tetra Examples thereof include isopropoxy tin, tetrabutoxy tin, tetrabutyl tin, zinc di (2,4-pentanedionate), propylene hexafluoride, cyclobutane octafluoride, and methane tetrafluoride.
[0115]
The ratio of the organometallic compound necessary for forming the transparent conductive film to the thin film forming gas for doping differs depending on the type of the transparent conductive film to be formed. For example, ITO obtained by doping indium oxide with tin is used. In the film, it is necessary to control the amount of the thin film forming gas so that the atomic ratio of the ratio of In to Sn is in the range of 100: 0.1 to 100: 15. Preferably, control is performed so as to be 100: 0.5 to 100: 10. In a transparent conductive film (referred to as FTO film) obtained by doping tin oxide with fluorine, the atomic ratio of the ratio of Sn to F in the obtained FTO film is in the range of 100: 0.01 to 100: 50. It is preferable to control the amount ratio of the thin film forming gas. In₂O₃-In the ZnO-based amorphous transparent conductive film, it is preferable to control the amount ratio of the thin film forming gas so that the atomic ratio of the ratio of In to Zn is in the range of 100: 50 to 100: 5. The respective atomic ratios of the In: Sn ratio, Sn: F ratio and In: Zn ratio can be determined by XPS measurement.
[0116]
In the present invention, the transparent conductive thin film forming gas is preferably contained in an amount of 0.01 to 10% by volume based on the mixed gas.
[0117]
In the present invention, the obtained transparent conductive film is, for example, SnO₂, In₂O₃, ZnO oxide film, or Sb-doped SnO₂, F-doped SnO₂(FTO), Al-doped ZnO, Sn-doped In₂O₃A composite oxide doped with a dopant such as (ITO) can be given, and an amorphous film containing at least one selected from these as a main component is preferable. In addition, chalcogenide, LaB₆, A non-oxide film such as TiN and TiC, a metal film such as Pt, Au, Ag, and Cu, and a transparent conductive film such as CdO.
[0118]
The thickness of the formed oxide or composite oxide transparent conductive film is preferably in the range of 0.1 to 1000 nm.
[0119]
The substrate used in the present invention will be described.
The base material used in the present invention is a sheet-shaped or film-shaped flat shape, as long as the thin film can be formed on the surface of the base material by exposing the thin film to a mixed gas in a plasma state while being continuously transferred. There is no particular limitation. Specifically, a resin lens, a resin film, a resin sheet, and the like can be given.
[0120]
Since the resin film can form a thin film by continuously transferring between the electrodes or in the vicinity of the electrodes of the atmospheric pressure plasma discharge treatment apparatus according to the present invention, it is not a batch type such as a vacuum system such as sputtering. It is suitable for production and is suitable as a continuous production method with high productivity.
[0121]
As the material of the resin film or the resin sheet, cellulose triacetate, cellulose diacetate, cellulose ester such as cellulose acetate propionate or cellulose acetate butyrate, polyester such as polyethylene terephthalate or polyethylene naphthalate, such as polyethylene or polypropylene Polyolefin, polyvinylidene chloride, polyvinyl chloride, polyvinyl alcohol, ethylene vinyl alcohol copolymer, syndiotactic polystyrene, polycarbonate, norbornene resin, polymethylpentene, polyetherketone, polyimide, polyethersulfone, polysulfone, polyetherimide, polyamide , Fluorine resin, polymethyl acrylate, acrylate copolymer, etc. It can be cited.
[0122]
These materials can be used alone or in a suitable mixture. Among them, ZEONEX and ZEONOR (manufactured by ZEON CORPORATION), ARTON (manufactured by Nippon Synthetic Rubber Co., Ltd.) of amorphous cyclopolyolefin resin film, PURE ACE (manufactured by Teijin Limited) of polycarbonate film, and Konica of cellulose triacetate film Commercial products such as Tuck KC4UX and KC8UX (manufactured by Konica Corporation) can be preferably used. Furthermore, even for materials having a large intrinsic birefringence such as polycarbonate, polyarylate, polysulfone, and polyethersulfone, conditions such as solution casting film formation and melt extrusion film formation, and further stretching conditions in the longitudinal and transverse directions. What can be used can be obtained by appropriately setting the above.
[0123]
Of these, a cellulose ester film that is optically nearly isotropic is preferably used for the optical thin film according to the present invention. As the cellulose ester film, one of those preferably used is a cellulose triacetate film or a cellulose acetate propionate as described above. As the cellulose triacetate film, commercially available Konikatak KC4UX is useful.
[0124]
Those having a surface coated with gelatin, polyvinyl alcohol, acrylic resin, polyester resin, cellulose ester resin or the like can be used. Further, an antiglare layer, a clear hard coat layer, a barrier layer, an antifouling layer and the like may be provided on the thin film side of these resin films. Further, an adhesive layer, an alkali barrier coat layer, a gas barrier layer, a solvent-resistant layer, and the like may be provided as necessary.
[0125]
Further, the substrate used in the present invention is not limited to the above description. The thickness of the film is preferably from 10 to 1000 μm, more preferably from 40 to 200 μm.
[0126]
Next, a coating layer useful for the antireflection film of the present invention will be described.
The antireflection layer or other thin film of the present invention may be formed directly on the above-mentioned film-like or sheet-like base material, or may be formed thereon via another layer.
[0127]
In the present invention, examples of the coating layer (coating layer on the thin film forming side) applied to the surface on the thin film forming side of the substrate include a clear hard coat layer, an antiglare layer, an adhesive layer, an antistatic layer, and the like. A hard coat layer, an antiglare layer, and an antistatic layer are preferably applied, particularly, in the case of an antireflection film, a clear hard coat layer or an antiglare film to increase the surface hardness of the antireflection film. It is preferable to provide it as “another layer”. Further, a back coat layer may be provided on the side opposite to the side on which the antireflection layer or other thin film is formed and the substrate.
[0128]
Here, a clear hard coat layer used in an antireflection film as a coating layer as “another layer” useful in the present invention will be described.
[0129]
The clear hard coat layer (the same composition for the antiglare layer) is preferably a layer containing an ultraviolet-curable compound (resin) that is cured by ultraviolet rays, and an antireflection film having excellent scratch resistance can be obtained. .
[0130]
The ultraviolet-curable resin layer of the clear hard coat layer is preferably a resin layer formed by polymerizing a component containing an ethylenically unsaturated monomer. Here, the ultraviolet curable resin layer refers to a layer mainly composed of a resin which is cured by a cross-linking reaction or the like by irradiation of an actinic ray such as an electron beam in addition to ultraviolet rays. Typical examples of the ultraviolet curable resin include an ultraviolet curable resin and an electron beam curable resin, but a resin that is cured by irradiation with an actinic ray other than an ultraviolet ray or an electron beam may be used. Examples of the ultraviolet-curable resin include an ultraviolet-curable acrylic urethane-based resin, an ultraviolet-curable polyester acrylate-based resin, an ultraviolet-curable epoxy acrylate-based resin, an ultraviolet-curable polyol acrylate-based resin, and an ultraviolet-curable epoxy resin. I can do it.
[0131]
The UV-curable acrylic urethane-based resin is generally obtained by reacting a polyester polyol with an isocyanate monomer or a prepolymer, and further adding 2-hydroxyethyl acrylate and 2-hydroxyethyl methacrylate (hereinafter, methacrylate to methacrylate). Can be easily obtained by reacting an acrylate monomer having a hydroxyl group such as 2-hydroxypropyl acrylate (see, for example, JP-A-59-151110).
[0132]
The UV-curable polyester acrylate resin can be easily obtained by generally reacting a polyester polyol with 2-hydroxyethyl acrylate or 2-hydroxy acrylate monomer (see, for example, JP-A-59-151112). .
[0133]
Specific examples of the UV-curable epoxy acrylate resin include epoxy acrylate as an oligomer, a reactive diluent and a photoreaction initiator added to the oligomer, and reacted (for example, Japanese Patent Application Laid-Open No. No. 105738). As the photoreaction initiator, one or more of benzoin derivatives, oxime ketone derivatives, benzophenone derivatives, thioxanthone derivatives and the like can be selected and used.
[0134]
Specific examples of the ultraviolet-curable polyol acrylate resin include trimethylolpropane triacrylate, ditrimethylolpropane tetraacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, and alkyl-modified dipentaerythritol pentaacrylate. And the like.
[0135]
These resins are usually used together with a known photosensitizer. Further, the above-mentioned photoreaction initiator can also be used as a photosensitizer. Specific examples include acetophenone, benzophenone, hydroxybenzophenone, Michler's ketone, α-amyloxime ester, thioxanthone, and the like, and derivatives thereof. When an epoxy acrylate-based photoreactive agent is used, a sensitizer such as n-butylamine, triethylamine, tri-n-butylphosphine and the like can be used. The photoreaction initiator or the photosensitizer contained in the ultraviolet-curable resin composition excluding the solvent component that evaporates after coating and drying can be added in an amount of usually 1 to 10% by mass of the composition, It is preferably mass%.
[0136]
Examples of the resin monomer include, as one monomer having one unsaturated double bond, general monomers such as methyl acrylate, ethyl acrylate, butyl acrylate, vinyl acetate, benzyl acrylate, cyclohexyl acrylate, and styrene. Further, monomers having two or more unsaturated double bonds include ethylene glycol diacrylate, propylene glycol diacrylate, divinylbenzene, 1,4-cyclohexane diacrylate, 1,4-cyclohexyldimethyl adiacrylate, and the above-mentioned trimethylolpropane. Examples thereof include triacrylate and pentaerythritol tetraacrylic ester.
[0137]
For example, as the ultraviolet curable resin, ADEKA OPTOMER KR / BY series: KR-400, KR-410, KR-550, KR-566, KR-567, BY-320B (all manufactured by Asahi Denka Kogyo Co., Ltd.), Alternatively, Koeihard A-101-KK, A-101-WS, C-302, C-401-N, C-501, M-101, M-102, T-102, D-102, NS-101, FT -102Q8, MAG-1-P20, AG-106, M-101-C (all manufactured by Koei Chemical Industry Co., Ltd.), or Seika Beam PHC2210 (S), PHC @ X-9 (K-3), PHC2213, DP- 10, DP-20, DP-30, P1000, P1100, P1200, P1300, P1400, P1500, P1600, SCR900 (or more Dainichi Seika Kogyo Co., Ltd.), or KRM7033, KRM7039, KRM7130, KRM7131, UVECRYL29201, UVECRYL29202 (hereafter, Daicel UCB Co., Ltd.), or RC-5015, RC-5016, RC-5020, RC-5031, RC -5100, RC-5102, RC-5120, RC-5122, RC-5152, RC-5171, RC-5180, RC-5181 (all manufactured by Dainippon Ink and Chemicals, Inc.) 340 Clear (China Paint Co., Ltd.), Sunrad H-601 (Sanyo Kasei Kogyo Co., Ltd.), SP-1509, SP-1507 (Showa Kogaku Co., Ltd.), or RCC-15C (Grace Japan Co., Ltd.) Co., Ltd.), Aronix M-6100, M-8030, M-8060 (all manufactured by Toagosei Co., Ltd.) or other commercially available products.
[0138]
The ultraviolet curable resin layer can be applied by a known method.
As a solvent for applying the ultraviolet curable resin layer, for example, hydrocarbons, alcohols, ketones, esters, glycol ethers, and other solvents can be appropriately selected or mixed and used. . Preferably, the propylene glycol mono (alkyl group having 1 to 4 carbon atoms) alkyl ether is 5% by mass or more, more preferably 5% to 80% by mass of propylene glycol mono (alkyl group having 1 to 4 carbon atoms) alkyl ether ester. The solvent contained above is used.
[0139]
As a light source for forming a cured film layer of the ultraviolet curable resin by a photocuring reaction, any light source that generates ultraviolet light can be used. For example, a low-pressure mercury lamp, a medium-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a carbon arc lamp, a metal halide lamp, a xenon lamp, and the like can be used. Irradiation conditions differ depending on each lamp, but the irradiation light amount is 20 to 10000 mJ / cm.²About 50 to 2000 mJ / cm.²It is. It can be used by using a sensitizer having an absorption maximum in the near ultraviolet region to the visible region.
[0140]
After the UV curable resin composition is applied and dried, UV light is irradiated from a light source. The irradiation time is preferably 0.5 seconds to 5 minutes, and 3 seconds to 2 seconds based on the curing efficiency and work efficiency of the UV curable resin. Minutes are more preferred.
[0141]
It is preferable to add inorganic or organic fine particles to the cured film layer thus obtained in order to prevent blocking and to enhance abrasion resistance and the like. For example, inorganic fine particles include silicon oxide, titanium oxide, aluminum oxide, tin oxide, zinc oxide, calcium carbonate, barium sulfate, talc, kaolin, calcium sulfate, and the like, and organic fine particles include polymethacrylic acid. Methyl acrylate resin powder, acrylic styrene resin powder, polymethyl methacrylate resin powder, silicon resin powder, polystyrene resin powder, polycarbonate resin powder, benzoguanamine resin powder, melamine resin powder, polyolefin resin powder, polyester resin powder And a polyamide-based resin powder, a polyimide-based resin powder, and a polyfluoroethylene-based resin powder, and can be added to the ultraviolet-curable resin composition. The average particle size of these fine particle powders is preferably from 0.005 μm to 1 μm, and particularly preferably from 0.01 to 0.1 μm.
[0142]
It is desirable to mix the ultraviolet curable resin composition and the fine particle powder in a ratio of 0.1 to 10 parts by mass with respect to 100 parts by mass of the resin composition.
[0143]
The layer formed by curing the ultraviolet curable resin thus formed has a Ra of 0.1 to 50 nm even if the clear hard coat layer has a center line average roughness Ra of 1 to 50 nm specified in JIS B0601. An anti-glare layer of about 1 μm may be used.
[0144]
As a method of applying a clear hard coat layer, an antiglare layer, or a back coat layer to a substrate, a known method such as a gravure coater, a spinner coater, a wire bar coater, a roll coater, a reverse coater, an extrusion coater, an air doctor coater, etc. Can be used. The liquid film thickness (also referred to as wet film thickness) at the time of coating is about 1 to 100 μm, preferably 0.1 to 30 μm, and more preferably 0.5 to 15 μm.
[0145]
【Example】
Hereinafter, the present invention will be described in detail with reference to examples, but the present invention is not limited thereto.
[0146]
Example 1
As a substrate, a roll of Konica Cat KC8UX film (manufactured by Konica Corporation, cellulose triacetate film) was used, and set on an unwinder.
[0147]
(Preparation of a substrate having a back coat layer)
On one side of the KONICATAC KC8UX film, the back coat layer coating composition prepared below was applied by an extrusion coater so as to have a wet film thickness of 14 μm, dried at 85 ° C. and wound up, and a substrate having a back coat layer was formed. Produced.
[0148]
<Preparation of back coat layer coating composition>
Acetone 30 parts by mass
Ethyl acetate 45 parts by mass
Isopropyl alcohol 10 parts by mass
Diacetyl cellulose 0.6 parts by mass
Aerosil 200V 2% acetone dispersion 分散 0.2 parts by mass
(Preparation of substrate having clear hard coat layer)
The following clear hard coat layer composition was applied on the surface opposite to the back coat layer of the substrate having the back coat layer prepared above by an extrusion coater so that the liquid film thickness became 13 μm, and then heated to 80 ° C. After drying in the set drying section, 120 mJ / cm²And a substrate having a clear hard coat layer having a center line average surface roughness (Ra) of 13 nm with a dry film thickness of 3 μm was prepared and wound.
[0149]
<Clear hard coat layer composition>
Dipentaerythritol hexaacrylate monomer 60 parts by mass
Dipentaerythritol hexaacrylate dimer 20 parts by mass
20 parts by mass of dipentaerythritol hexaacrylate trimer or higher component
Dimethoxybenzophenone 4 parts by mass
Ethyl acetate 45 parts by mass
Methyl ethyl ketone 45 parts by mass
Isopropyl alcohol 60 parts by mass
(Preparation of antireflection film)
<Atmospheric pressure plasma discharge treatment equipment and thin film formation conditions>
《Preparation of electrode》
As a roll electrode shown in FIGS. 2 and 3, a jacket roll base material made of a titanium alloy T64 having a cooling function was coated with 1 mm of alumina by ceramic spraying, and a solution obtained by diluting tetramethoxysilane with ethyl acetate was further coated thereon. After coating and drying, the coating was cured by irradiation with ultraviolet light to perform a sealing treatment, thereby producing a roll electrode having an Rmax 1 μm dielectric. On the other hand, a rectangular pipe made of a hollow titanium alloy T64 as shown in FIG. 4 was used, and a dielectric material similar to that described above was coated under the same conditions to form a rectangular cylindrical electrode.
[0150]
《Atmospheric pressure plasma discharge treatment equipment》
Four atmospheric pressure plasma discharge treatment apparatuses shown in FIG. 2 were continuously arranged in series as shown in FIG. The roll rotating electrodes 235, 335, 435, and 535 are grounded to the ground, and the rectangular cylindrical fixed electrode groups 236, 336, 436, and 536 are arranged on an arc of the roll rotating electrode that is larger than the diameter thereof. Cylindrical fixed electrode groups 236, 336, 436 and 536 were connected to a high frequency power supply 13.56 MHz manufactured by Pearl Industries as high frequency power supplies for voltage applying means 240, 340, 440 and 540. A first plasma discharge processing apparatus 200 for forming a medium refractive index layer, a second plasma discharge processing apparatus 300 for forming a high refractive index layer, a third plasma discharge processing apparatus 400 for forming a low refractive index layer, and a fourth protection device. Four plasma discharge treatment apparatuses for forming a dirty layer were arranged in series. Further, after each plasma discharge treatment apparatus for forming the medium refractive index layer, forming the high refractive index layer, and forming the low refractive index layer, the film thickness control means 210, 310 and 410 are installed in this order, and measurement, feedback and control are performed. went. After the antifouling layer was formed, no film thickness control means was provided.
[0151]
《Thin film formation conditions》
In any of the atmospheric pressure plasma discharge treatment apparatuses, the pressure in the discharge space is set to 103 kPa, and the gas for the respective refractive index layers described below is mixed and supplied from the gas supply device to the discharge treatment space, and the gap between the counter electrodes (discharge space) ) Is set to 1.0 mm, a high frequency voltage of 13.56 MHz is applied, and 15 W / cm²Power density.
[0152]
<Preparation of a substrate having a medium refractive index layer>
On the clear hard coat layer of the base material having the clear hard coat layer and the back coat layer obtained above, the first medium-refractive index layer forming plasma discharge treatment apparatus, set to the initially given target value conditions, the following A medium-refractive-index layer is formed with a medium-refractive-index-layer thin-film forming gas, and a substrate having the medium-refractive-index layer is set at 400 nm, 450 nm, 600 nm, and 730 nm from the side of the medium-refractive index layer using a measurement header (probe) 214. The reflectance is measured at each wavelength of 780 nm and 780 nm, each measured value is sent to the arithmetic processing unit 216, the difference from the target value is calculated, and the result is sent to the film thickness control system 217 of the middle refractive index layer, The film thickness was corrected by changing the applied voltage. As a result, the target value was attained. Therefore, the formation of a thin film was continued under the same conditions, and a substrate having a target value and a medium refractive index layer was obtained. The measurement, calculation, feedback, and control were always performed during the formation of the full-length thin film. The expression of the clear hard coat layer was omitted, and a substrate having a medium refractive index layer was used.
[0153]
《Medium refractive index gas》
Discharge gas: Argon 98.7% by volume
Thin film forming gas for medium refractive index layer: Tetrabutyltin vapor @ 0.3% by volume
Auxiliary gas: hydrogen gas 1% by volume
<Substrate having medium / high refractive index layer>
Subsequently, a high-refractive-index layer is formed on the medium-refractive-index layer having the target value obtained above by setting a target value condition initially given and using a thin-film forming gas for a high-refractive-index layer described below. The reflectance of the substrate having the refractive index layer is measured at the set wavelengths of 400 nm, 450 nm, 600 nm, 730 nm, and 780 nm with the measurement header (probe) 314 from the side of the high refractive index layer, and each measured value is processed by an arithmetic processing unit. 316, the difference from the target value is calculated, and the result is sent to the film thickness control system 317 for the high refractive index layer, and the film thickness is corrected by changing the high frequency applied voltage. As a result, the target value was attained, and the formation of a thin film was continued under the same conditions to obtain a substrate having a target value of a medium refractive index layer / high refractive index layer. The measurement, calculation, feedback, and control were always performed during the formation of the full-length thin film. The clear hard coat layer on the base material, the medium refractive index layer on the clear hard coat layer, and the high refractive index layer on the clear hard coat layer are expressed as "medium refractive index layer / high refractive index layer".
[0154]

Subsequently, a low-refractive-index layer is formed on the high-refractive-index layer having the target value obtained above by setting the target value condition initially given and using a low-refractive-index layer thin-film forming gas described below. The base material having the refractive index layer is measured from the low refractive index layer side by the measurement header (probe) 414 at the set wavelengths of 400 nm, 450 nm, 600 nm, 730 nm and 780 nm, and the measured values are processed by the arithmetic processing unit. 416, the difference from the target value is calculated, and the result is sent to the film thickness control system 417 for the low refractive index layer, and the film thickness is corrected by changing the high frequency applied voltage. As a result, since the target value was obtained, the thin film formation was continued under the same conditions, and the base material having the target value of the middle refractive index layer, the high refractive index layer, and the low refractive index layer (medium refractive index layer / high refractive index layer) Layer / substrate having a low refractive index layer). The measurement, calculation, feedback, and control were always performed during the formation of the full-length thin film.
[0155]
<Low refractive index gas>
Discharge gas: Argon 98.7% by volume
Thin film forming gas for low refractive index layer: tetraethoxysilane vapor ： 0.3% by volume
Auxiliary gas: hydrogen gas 1% by volume
<Preparation of antireflection film>
A plasma discharge treatment apparatus for forming a fourth antifouling layer on the low refractive index layer of the substrate having the medium refractive index layer / high refractive index layer / low refractive index layer. Thus, an antireflection film was prepared by using the following antifouling layer thin film forming gas. Here, the film thickness control was not performed.
[0156]

In addition, the refractive index of the tin oxide layer of the middle refractive index layer is 1.7, the film thickness is 67 nm, the refractive index of the titanium oxide layer of the high refractive index layer is 2.14, the film thickness is 110 nm, and the oxidation of the low refractive index layer is With a refractive index of the silicon layer of 1.44, a thickness of 87 nm, and a thickness of the silicon fluoride layer of the antifouling layer of 1.2 nm, a four-layered antireflection film was obtained.
[0157]
Comparative Example 1
Initially, only the setting conditions were set to the target value conditions, the thin film formation was continued to the end without performing any control of the high frequency applied voltage, and three layers were stacked. Further, in each layer formation, the measurement header of the reflectometer was measured. The same procedure as in Example 1 was performed except that the measurement, calculation, feedback, and control of the reflectance by the (probe) were not performed, to obtain an antireflection film having a middle refractive index layer / high refractive index layer / low refractive index layer laminate. Was.
[0158]
Comparative Example 2
Thin film forming gas for medium refractive index layer among gases for medium refractive index, thin film forming gas for high refractive index layer among gases for high refractive index, and thin film forming gas for low refractive index layer among gases for low refractive index Example 1 Except that each organometallic compound as a gas was lowered by 5% by mass and the measurement, calculation, feedback and control of the reflectance by the measurement header (probe) of the reflectance measuring device were not performed in each layer formation. In the same manner as described above, an antireflection film having a middle refractive index layer / high refractive index layer / low refractive index layer laminate was obtained.
[0159]
Comparative Example 3
Thin film forming gas for medium refractive index layer among gases for medium refractive index, thin film forming gas for high refractive index layer among gases for high refractive index, and thin film forming gas for low refractive index layer among gases for low refractive index Example 1 was repeated except that the organometallic compound as a gas was increased by 5% by mass, and that the measurement, calculation, feedback, and control of the reflectance by the measurement header (probe) of the reflectance measuring device were not performed in each layer formation. In the same manner, an antireflection film having a middle refractive index layer / high refractive index layer / low refractive index layer stack was obtained.
[0160]
[Evaluation]
<Difference from target value of reflectance>
Five samples were taken from the obtained long antireflection film in the width direction every 100 m, and the reflectance of these 75 samples was measured by a thickness measurement system MCPD manufactured by Otsuka Electronics Co., Ltd. The difference between the average value of the reflectance of 75 samples and the target value was determined.
[0161]
<Coloring>
In the same manner as described above, each of the 75 samples was examined for coloring, and evaluated at the following levels.
[0162]
A: almost no color
B: Slight color
C: There is considerable color
D: Colored and uneven.
[0163]
Table 4 shows the evaluation results of Example 1 and Comparative Examples 1 to 3.
[0164]
[Table 4]

[0165]
(result)
As can be seen from Table 4, in the present invention, the reflectance was almost the target value, coloring was hardly recognized, and an excellent antireflection film could be obtained. On the other hand, the comparative example was an antireflection film in which the reflectance was considerably different from the target value, and the coloring was clearly recognized.
[0166]
Example 2
On the high refractive index layer of the substrate having the middle refractive index layer / high refractive index layer stack obtained in Example 1, the target initially set by the third plasma discharge processing apparatus for forming a low refractive index layer was used. A low-refractive-index layer was formed with the following low-refractive-index gas under the value conditions. The reflection spectrum of the entire visible light region is measured by the measurement header (probe) 34 from the low refractive index layer side of the substrate having the middle refractive index layer / high refractive index layer / low refractive index layer stack, and the above-described color difference equation is obtained. The measured value is sent to the arithmetic processing unit, the difference from the target value is calculated, the result is sent to the film thickness control system of the low refractive index layer, and the formation of the low refractive index layer is continued. Since the measured value was the target value, a thin film was formed under the conditions, and the antifouling layer was further laminated on the low refractive index layer using the fourth antifouling layer forming plasma discharge treatment apparatus. An antireflection film having a middle refractive index layer / high refractive index layer / low refractive index layer laminate with a value was obtained. The measurement, calculation, feedback, and control were always performed during the formation of the full-length thin film.
[0167]
Comparative Example 4
A low-refractive-index layer was formed on the high-refractive-index layer of the substrate having the middle-refractive-index layer / high-refractive-index layer laminate obtained in Example 1 only by first setting the conditions to target values. , The reflection spectrum was measured for the entire length by the measurement header (probe) of the reflectometer, and the reflection spectrum was converted to a color difference formula and the data was output, but the calculation and the feedback preliminary control were not performed. The procedure was performed in the same manner as in Example 2 except for the above.
[0168]
Comparative Example 5
On the high-refractive-index layer of the substrate having the middle-refractive-index layer / high-refractive-index layer laminate obtained in Example 1, only the initially set conditions were applied, and only the low-refractive-index gas was used. Each organometallic compound as a thin film forming gas for a low refractive index layer was lowered by 3% by mass to obtain an antireflection film having a middle refractive index layer / a high refractive index layer / a low refractive index layer laminate. The reflection spectrum was measured for the entire length of the visible light region by the measurement header (probe), and the reflection spectrum was converted to a color difference equation and the data was output. However, the calculation and feedback preliminary control were not performed. The same procedure was followed.
[0169]
Comparative Example 6
On the high-refractive-index layer of the substrate having the middle-refractive-index layer / high-refractive-index layer laminate obtained in Example 1, only the initially set conditions were applied, and only the low-refractive-index gas was used. Each organic metal compound as a thin film forming gas for a low refractive index layer was increased by 3% by mass to obtain an antireflection film having a middle refractive index layer / high refractive index layer / low refractive index layer stack. The reflection spectrum was measured for the entire length of the visible light region by the measurement header (probe), and the reflection spectrum was converted to a color difference equation and the data was output. However, the calculation and feedback preliminary control were not performed. The same procedure was followed.
[0170]
The colors of the antireflection films of Example 2 and Comparative Examples 4 to 6 were evaluated by the following methods. Table 5 shows the results.
[0171]
[Evaluation]
<ΔE^*ab>
ΔE in the above color difference equation^*Ab values were expressed at the following levels.
[0172]
A: 0 or more and less than 0.5 (no difference or very slightly different)
B: 0.5 or more and less than 1.5 (slightly different)
C: 1.5 or more and less than 3.0 (differently perceptible)
D: 3.0 or more and less than 6.0 (notably different)
E: 6.0 or more (very different)
[0173]
[Table 5]

[0174]
(result)
In Example 2 in which the reflection spectrum in the visible light region was converted into a color difference equation and the coloring was fed back to the film thickness control system to control the coloring, it was found that this method could also substantially eliminate the coloring. On the other hand, in Comparative Examples 4 to 6, since the same feedback and control as described above were not performed, coloring was conspicuous.
[0175]
【The invention's effect】
According to the present invention, it is possible to provide an antireflection film having almost no reflection and having almost no color seen by reflection.
[Brief description of the drawings]
FIG. 1 is a view showing a reflection spectrum in a visible light wavelength region of an antireflection film (base material / medium refractive index layer / high refractive index layer / low refractive index layer laminate).
FIG. 2 is a schematic view showing an example of an atmospheric pressure plasma discharge thin film forming apparatus according to the present invention.
3 is a perspective view showing an example of a structure of a conductive metallic base material of a roll rotating electrode shown in FIG. 2 and a dielectric material coated thereon.
FIG. 4 is a perspective view showing an example showing a structure of a base material of a rectangular cylindrical electrode shown in FIG. 2 and a dielectric material coated thereon.
FIG. 5 is a diagram showing an example of an atmospheric pressure plasma discharge processing apparatus in which four thin film layers are continuously stacked in which the atmospheric pressure plasma discharge processing apparatus of FIG. 2 is installed in series.
[Explanation of symbols]
Plasma discharge treatment apparatus for forming 200 ° medium refractive index layer
210, 310, 410—film thickness control means
235,335,435 roll electrode
236, 336, 436 square cylindrical fixed electrode group
240, 340, 440 ° voltage applying means
Plasma discharge treatment apparatus for forming 300 ° high refractive index layer
400 ° plasma discharge treatment apparatus for forming low refractive index layer

Claims (9)

In a method of forming an optical thin film by discharge plasma under atmospheric pressure or a pressure close to the atmospheric pressure directly or through another layer on a base material, after forming the optical thin film on the base material, The reflectance of two or more wavelengths set in the optical wavelength region is measured by an on-line reflectance measuring instrument, and each of the predetermined standard reflectances at the two or more wavelengths is compared with the measured reflectance. And calculating the result, feeding back the result to a film thickness control system, and controlling the film thickness of the optical thin film. Directly or through another layer on the substrate to be continuously transferred, in a method of forming an optical thin film by discharge plasma under atmospheric pressure or a pressure in the vicinity thereof, after forming the optical thin film on the substrate, The reflectance of the optical thin film at two or more wavelengths set in the visible light wavelength region is measured by an on-line reflectance measurement device, and the standard reflectances predetermined at the two or more wavelengths and the measurement are performed. A method of forming an optical thin film, comprising comparing and calculating the calculated reflectance, feeding back the result to a film thickness control system, and controlling the film thickness of the optical thin film. In a method for producing an antireflection film, in which an antireflection film is formed by discharge plasma under atmospheric pressure or a pressure close thereto, directly or through another layer, on a substrate to be continuously transferred, After forming the anti-reflection layer, the reflectance of the anti-reflection layer at two or more wavelengths set in the visible light wavelength region was measured by an on-line reflectometer, and the reflectance at the two or more wavelengths was determined in advance. A method of manufacturing an anti-reflection film, comprising comparing and calculating each standard reflectance with the measured reflectance, feeding back the result to a film thickness control system, and controlling the film thickness of the anti-reflection layer. Directly or through another layer on the substrate to be continuously transferred, in the method of manufacturing an anti-reflection film to form each anti-reflection layer by discharge plasma under atmospheric pressure or a pressure in the vicinity thereof, on the substrate After successively forming two or more adjacent anti-reflection layers having different refractive indices, the reflectance of two or more wavelengths set in the visible light wavelength region with respect to the laminated anti-reflection layer after formation of each anti-reflection layer is measured online. The reflectance is measured by a reflectance measuring device, and the standard reflectance predetermined at the two or more wavelengths and the measured reflectance are compared and calculated, and the result is fed back to the film thickness control system every time the antireflection layer is formed. And a method for producing an anti-reflection film, wherein the thickness of each anti-reflection layer is controlled. In a method for producing an antireflection film, in which an antireflection film is formed by discharge plasma under atmospheric pressure or a pressure close thereto, directly or through another layer, on a substrate to be continuously transferred, After forming the anti-reflection layer, the reflectance of one or more wavelengths set in each of the two wavelength ranges of 380 to 550 nm and 600 to 800 nm for the anti-reflection layer is measured by an on-line reflectometer. Measure and compare a predetermined standard reflectance at the one or more wavelengths with the measured reflectance, calculate the result, and feed back the result to a film thickness control system to control the film thickness of the antireflection layer. A method for producing an antireflection film, comprising: In a method for producing an antireflection film in which an antireflection layer is formed by discharge plasma under atmospheric pressure or a pressure close thereto, directly or via another layer, on a substrate to be continuously transferred, After successive formation of adjacent antireflection layers having different refractive indices of at least one layer, the laminated antireflection layers after formation of each antireflection layer are set in respective wavelength regions of 380 to 550 nm and two wavelength regions of 600 to 800 nm. The reflectance at one or more wavelengths is measured by an on-line reflectance measuring instrument, and the standard reflectances determined at the one or more wavelengths are compared with the measured reflectances, and the result is calculated. A method for producing an anti-reflection film, wherein the thickness of each anti-reflection layer is controlled by feeding back to the film thickness control system each time the anti-reflection layer is formed. In a method for producing an anti-reflection film by forming an anti-reflection layer by discharge plasma under atmospheric pressure or a pressure in the vicinity thereof, directly or through another layer on a substrate to be continuously transferred, an uppermost layer is formed on the substrate. The reflection spectrum of the uppermost layer is measured by an on-line reflectometer, and the color difference or tristimulus value (X, Y) from the L ^* a ^* b ^* color space is measured based on the measured reflection spectrum. obtains a Z), the predetermined color difference or tristimulus values from the ^L * ^a * ^{b *} color space from the standard reflection spectrum (X, Y, Z) and, measured ^L than the reflection spectrum obtained by * ^{a *} b ^* Computing by comparing the color difference or tristimulus value (X, Y, Z) from the color space, and feeding back the result to the uppermost layer thickness control system to control the formation condition of the uppermost antireflection layer. Characterized by reflection Method of manufacturing a stop film. The antireflection film according to claim 4, wherein three layers of a middle refractive index layer, a high refractive index layer, and a low refractive index layer are sequentially stacked on the base material from the base material side. Manufacturing method. An antireflection film manufactured by the method for manufacturing an antireflection film according to claim 3.

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