JP4522505B2 - Transparent conductive film-forming coating liquid, transparent conductive film-coated substrate, and display device - Google Patents

Transparent conductive film-forming coating liquid, transparent conductive film-coated substrate, and display device Download PDF

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JP4522505B2
JP4522505B2 JP37445198A JP37445198A JP4522505B2 JP 4522505 B2 JP4522505 B2 JP 4522505B2 JP 37445198 A JP37445198 A JP 37445198A JP 37445198 A JP37445198 A JP 37445198A JP 4522505 B2 JP4522505 B2 JP 4522505B2
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conductive film
transparent conductive
forming
coating liquid
metal
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JP2000196287A (en
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井 俊 晴 平
原 庸 一 石
澤 光 章 熊
迫 祐 二 俵
松 通 郎 小
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JGC Catalysts and Chemicals Ltd
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Catalysts and Chemicals Industries Co Ltd
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Description

【0001】
【発明の技術分野】
本発明は、透明導電性被膜形成用塗布液、透明導電性被膜付基材および該基材を前面板として備えた表示装置に関し、さらに詳しくは、帯電防止性、電磁遮蔽性、透明性、反射防止性等に優れた透明導電性被膜付基材を形成可能な塗布液、および該塗布液を使用して得られた該透明導電性被膜付基材、該透明導電性被膜付基材で構成された前面板を備えた表示装置に関する。
【0002】
【発明の技術的背景】
従来より、陰極線管、蛍光表示管、液晶表示板などのような表示パネルの透明基材の表面の帯電防止および反射防止を目的として、これらの表面に帯電防止機能および反射防止機能を有する透明被膜を形成することが行われていた。
【0003】
ところで、陰極線管などから放出される電磁波が人体に及ぼす影響が、最近問題にされており、従来の帯電防止、反射防止に加えてこれらの電磁波および電磁波の放出に伴って形成される電磁場を遮蔽することが望まれている。
【0004】
これらの電磁波などを遮蔽する方法の一つとして、陰極線管などの表示パネルの表面に電磁波遮断用の導電性被膜を形成する方法がある。しかし、従来の帯電防止用導電性被膜であれば表面抵抗が少なくとも107Ω/□程度の表面抵抗を有していれば十分であるのに対し、電磁遮蔽用の導電性被膜では102〜104Ω/□のような低い表面抵抗を有することが必要であった。
【0005】
従来から使用されていたSbドープ酸化錫およびSnドープ酸化インジウムなどの導電性酸化物を含む塗布液を用いて、このような表面抵抗の低い導電性被膜を形成すると、従来の帯電防止性被膜の場合よりも膜厚を厚くする必要があった。しかしながら、導電性被膜の膜厚は、10〜200nm程度にしないと反射防止効果は発現しないため、従来のSbドープ酸化錫およびSnドープ酸化インジウムなどの導電性酸化物では、表面抵抗が低く、電磁波遮断性に優れるとともに、反射防止にも優れた導電性被膜を得ることが困難であるという問題があった。
【0006】
また、低表面抵抗の導電性被膜を形成する方法の一つとして、Agなどの金属微粒子を含む導電性被膜形成用塗布液を用いて基材の表面に金属微粒子含有被膜を形成する方法がある。この方法では、金属微粒子含有被膜形成用塗布液として、コロイド状の金属微粒子が極性溶媒に分散したものが用いられている。このような塗布液では、コロイド状金属微粒子の分散性を向上させるために、金属微粒子表面がポリビニルアルコール、ポリビニルピロリドンまたはゼラチンなどの有機系安定剤で表面処理されている。しかしながら、このような金属微粒子含有被膜形成用塗布液を用いて形成された導電性被膜は、被膜中で金属微粒子同士が安定剤を介して接触するため、粒界抵抗が大きく、被膜の表面抵抗が低くならないことがあった。このため、成膜後、400℃程度の高温で焼成して安定剤を分解除去する必要があるが、安定剤の分解除去をするため高温で焼成すると、金属微粒子同士の融着や凝集が起こり、導電性被膜の透明性やへーズが低下するという問題があった。また、陰極線管などの場合は、高温に晒すと劣化してしまうという問題もあった。
【0007】
さらに従来のAg等の金属微粒子を含む透明導電性被膜では、金属が酸化されたり、イオン化による粒子成長したり、また場合によっては腐食が発生することがあり、塗膜の導電性や光透過率が低下し、表示装置が信頼性を欠くという問題があった。
【0008】
また、従来の透明導電性被膜では単分散した微粒子が用いられたため、マトリックスの影響、粒子表面に残存する有機安定剤、溶媒、あるいは粒界抵抗等に起因して充分な低抵抗膜が得られない場合、さらには充分な再現性が得られない場合があり、このため、例えば膜の抵抗を低くするために膜厚を厚くするなどすると透明性が低下する等の問題があった。
【0009】
【発明の目的】
本発明は、上記のような従来技術の問題点を解決すべくなされたものであって、102〜104Ω/□程度の低い表面抵抗を有し、帯電防止性、透明性、反射防止性、防眩性および電磁遮蔽性に優れるとともに、信頼性にも優れた透明導電性被膜を形成しうる透明導電性被膜形成用塗布液、透明導電性被膜付基材、該基材を前面板として備えた表示装置を提供することを目的としている。
【0010】
【発明の概要】
本発明に係る第1の透明導電性被膜形成用塗布液は、
導電性微粒子と極性溶媒とを含む透明導電性被膜形成用塗布液において、
導電性微粒子が、平均粒子径が1〜100nmの範囲にある一次粒子が2個以上鎖状に連続して接合した鎖状構造を有する鎖状導電性微粒子群からなることを特徴としている。
【0013】
【発明の具体的説明】
以下、本発明について具体的に説明する。
[第1の透明導電性被膜形成用塗布液]
まず、本発明に係る第1の透明導電性被膜形成用塗布液について説明する。
【0014】
本発明に係る透明導電性被膜形成用塗布液は、鎖状導電性微粒子群と極性溶媒とを含む。
鎖状導電性微粒子群
本発明でいう「鎖状導電性微粒子群」とは、図1に示すように平均粒子径が1〜100nm、好ましくは5〜80nmの一次粒子が少なくとも2個以上鎖状に連続して結合した鎖状構造を有する微粒子をいう。
【0015】
このような鎖状導電性微粒子群は、一次粒子が単に粒子間引力等によって凝集しているのとは相異し、金属粒子同士である場合は金属結合によって、酸化物粒子同士である場合は酸素を介して結合している。さらには、図2に示されるように、「ネック」と呼ばれる粒子の接点部分に一次粒子と同一または異なる成分が結合して一次粒子は互いに面で結合していてもよい。このような鎖状導電性微粒子群は直線状であっても、ジグザグ状であってもよく、弓状に湾曲していてもよい。さらには、図3に示されるように、鎖状導電性微粒子群の末端同士が接合したリング状であってもよい。
【0016】
このような鎖状導電性微粒子群を構成する一次粒子の間には粒界抵抗がなく、有機安定剤、溶媒も存在し得ないので、鎖状導電性微粒子群を含む塗布液を塗布して得られる被膜の抵抗が減少し、低い抵抗の被膜が得られる。
【0017】
導電性微粒子の平均一次粒径が100nmを越えると、鎖状導電性微粒子群の形成が困難となり、また仮にできたとしても導電層中の粒子の接点が減少するために低い抵抗値を有する透明導電性被膜を得ることが困難となる。さらに、平均一次粒径が100nmを越えると、導電性微粒子による光の吸収が大きくなり、被膜の光透過率が低下したり被膜のへーズが大きくなることがあり、このような平均一次粒径が100nmを越えた導電性微粒子を含む被膜付基材を、たとえば陰極線管の前面板として用いると、表示画像の明るさ不充分となり、このため一定の透過率を得るために膜厚を薄くしたり、導電性微粒子の量を少なくしようとすると充分な導電性が得られないことがある。
【0018】
また、導電性微粒子の平均粒径が1nm未満の場合には粒界抵抗が急激に大きくなるため、本発明の目的を達成しうる程度の低い抵抗値を有する透明導電性被膜を得ることができないこともある。また、粒子が小さいために鎖状導電性微粒子群が得られず3次元に凝集した粒子が増加する傾向にあり、低い抵抗値を有する導電性被膜を得ることができないこともある。
【0019】
このような鎖状導電性微粒子群の平均長さは、2〜200nm、好ましくは5〜80nmの範囲にある。
平均長さが2nm未満では、接触抵抗が増加し、低抵抗の透明導電性被膜が得られないことがあり、また平均長さが200nmを超えると、透明導電性被膜の形成性が低下し、ヘーズ等の光学特性に問題が生じ、さらに外観が悪化するなどの問題がある。
【0020】
なお、本発明では、導電性微粒子がすべて上記のような鎖状導電性微粒子群を形成してもよいが、導電性微粒子の少なくとも一部が鎖状導電性微粒子群を形成していてもよい。このときの鎖状導電性微粒子群の割合は、導電性微粒子中に5%以上の量で含まれていることが望ましい。鎖状導電性微粒子群の割合が5%未満では、抵抗を低下させる効果が不充分になることがある。
【0021】
このような鎖状導電性微粒子群は、Au,Ag,Pd,Cu,Ni,Ru,Rh,Sn,In,Sb,Fe,Pt,Ti,Cr,Co,Al,Zn,Ta,Pb,Os,Irから選ばれる一種以上の元素からなる金属および/または金属水酸化物または金属酸化物、あるいは異種金属ドープ金属酸化物、これらの混合物からなることが好ましい。
【0022】
鎖状導電性微粒子群が2種以上の元素からなる金属微粒子である場合、好ましい金属の組合せとしては、Au-Cu,Ag-Pt,Ag-Pd,Au-Pd,Au-Rh,Pt-Pd,Pt-Rh,Fe-Ni,Ni-Pd,Fe-Co,Cu-Co,Ru-Ag,Au-Cu-Ag,Ag-Cu-Pt,Ag-Cu-Pd,Ag-Au-Pd,Au-Rh-Pd,Ag-Pt-Pd,Ag-Pt-Rh,Fe-Ni-Pd,Fe-Co-Pd,Cu-Co-Pd などが挙げられる。なお、鎖状導電性微粒子群を構成する2種以上の金属は、固溶状態にある合金であっても、固溶状態にない共晶体であってもよく、合金と共晶体が共存していてもよい。鎖状導電性微粒子群が2種以上の金属から構成されると、金属の酸化やイオン化あるいはイオンマイグレーションが抑制されるため、被膜形成後の導電性微粒子の粒子成長等が抑制される。また、2種以上の金属から構成される鎖状導電性微粒子群は、耐腐食性が高く、導電性、光透過率の低下が小さいので、信頼性に優れた透明導電性被膜を形成することができる。
【0023】
導電性微粒子が金属酸化物、あるいは異種金属ドープ金属酸化物である場合の好ましい例としては、たとえば酸化錫、Sb、FまたはPがドーピングざれた酸化錫、酸化インジウム、SnまたはFがドーピングされた酸化インジウム、酸化アンチモン、低次酸化チタンなどが挙げられる。
【0024】
このような鎖状導電性微粒子群は、金属微粒子分散スラリーまたは金属水酸化物ゲルスラリーに加熱処理を行ったのち、メカニカル分散処理を行い得られたものが好ましい。
【0025】
具体的に鎖状導電性微粒子群は、以下のような方法によって調製される。
(1)たとえば金属から構成される鎖状導電性微粒子群の場合、以下のような方法によって得ることができる。
【0026】
まず、アルコール・水混合溶媒中で、金属塩を還元して一次粒子径が1〜100nmの金属微粒子分散スラリーを調製する。このとき、通常、還元剤が添加される。還元剤としては、硫酸第1鉄、クエン酸3ナトリウム、酒石酸、水素化ホウ素ナトリウム、ヒドラジン、次亜リン酸ナトリウムなどが使用される。なお、金属塩を2種以上使用する場合、2種以上の金属塩を同時に還元してもよく、また個々の金属塩を還元したのち、混合してもよい。
【0027】
得られた金属微粒子分散スラリーは、イオン性不純物を除去しておくことが望ましい。イオン性不純物を除去する方法は特に限定されるものではなく、たとえば、カチオン性、アニオン性または両性のイオン交換樹脂で処理する方法等が挙げられる。イオン性不純物は、導電性微粒子の塗布液中の量によって、異なるものの、塗布液中のイオン濃度が1000ppm以下となるような量であることが望ましい。イオン性不純物の量が1000ppm以下であれば塗布液の安定性が高く(ポットライフが長く)することができ、さらには、被膜形成時に導電性微粒子が凝集することが少なくなるので平滑な被膜を形成できる。
【0028】
次に、得られた金属微粒子分散スラリーにメカニカル分散処理を行うこともできる。このメカニカル分散処理によって、生成ゲルが解膠し、鎖状導電性微粒子群が分散したゾルが得られる。このようなメカニカル分散処理としては、サンドミル法、衝撃分散法などが挙げられ、特に、衝撃分散法が好ましく使用される。衝撃分散法は、音速程度などの高速でスラリーを壁に衝突させて分散または粉砕させる方法であり、たとえばArtimizer、Nanomizer等の装置を用いて行われる。このような方法では、粒子内の結合が切断して結晶性が無定型化したり、OH基などの表面官能基の生成による導電性が低下したりすることがなく、安定に分散した鎖状導電性微粒子群分散ゾルが得られるので好ましい。
【0029】
なお、メカニカル分散処理を行う際には、安定剤を添加してもよい。安定剤として具体的には、ゼラチン、ポリビニルアルコール、ポリビニルピロリドン、シュウ酸、マロン酸、コハク酸、グルタール酸、アジピン酸、セバシン酸、マレイン酸、フマル酸、フタル酸、クエン酸などの多価カルボン酸およびその塩、複素環化合物あるいはこれらの混合物などが挙げられる。導電性微粒子調製時に使用される安定剤は、後述する塗布液に添加される安定剤と同じであっても異なっていてもよく、また安定剤の使用量は、安定剤のCMC(臨界ミセル生成濃度)の5〜50%、好ましくは5〜30%の範囲であることが望ましい。
【0030】
安定剤の量がCMCの5%未満では、粒子表面の安定剤の量が少ないため、3次元に連結した非鎖状の粒子が生成することがあり、安定剤の量がCMCの50%を越えると鎖状導電性微粒子群の生成せずに単分散粒子が多くなり、鎖状導電性微粒子群の導電パス形成による導電層の抵抗の低下効果が得られないことがある。
【0031】
(2)また、金属から構成される鎖状導電性微粒子群は、上記以外に、以下の方法で調製することができる。
まず、前記同様にアルコール・水混合溶媒中で、金属塩を還元して一次粒子径が1〜100nmの金属微粒子分散スラリーを調製する。このとき、通常、還元剤が添加される。還元剤としては、前記と同じものが挙げられる。
【0032】
次に、調製した金属微粒子分散スラリーを圧力容器などを使用した加圧下で加熱処理(以後この処理をオートクレーブ処理という)する。このようなオートクレーブ処理は、通常、約100〜250℃の温度で行われる。この際、安定剤を添加してもよく、安定剤の種類および使用量は前記と同様である。また、この加熱処理を行う際、金属微粒子分散スラリーの攪拌の有無によって、鎖状導電性微粒子群の生成割合および鎖状導電性微粒子群の長さを制御することができる。
【0033】
オートクレーブ処理したのち、前記のようなメカニカル分散処理を行う。
また、オートクレーブ処理を行うに際して、さらに金属塩を添加してもよい。使用される金属塩としては、金属微粒子分散スラリー調製時に使用したものと同じものであっても、異なるものであってもよい。このような金属塩を添加していると、加熱処理時に、ネック部に金属のイオンマイグレーションし、粒子の接合が点接合から面接合になり、図2に示されるような「ネック」部を有する鎖状導電性微粒子群が得られる。
【0034】
(3)さらにまた、金属から構成される鎖状導電性微粒子群は、以下の方法で調製することもできる。
まず、アルコール・水混合溶媒中で、還元剤および有機安定剤の存在下で、金属塩を還元する。この際、使用される還元剤および有機安定剤としては、前記と同様のものが例示される。なお、有機系安定剤は、生成する金属微粒子1重量部に対し、0.005〜0.5重量部、好ましくは0.01〜0.2重量部含まれていればよい。有機系安定剤の量が0.005重量部未満の場合は充分な分散性が得られず、0.5重量部を超えて高い場合は、鎖状導電性微粒子群の生成が少なく単分散粒子が多くなり、さらに過剰の有機系安定剤が存在すると凝集粒子が生成することがあり、また残留する有機安定剤により導電性が阻害されることがある。
【0035】
この方法でも、図2に示されるように、「ネック」を有する鎖状導電性微粒子群を有することができる。
(4)また、鎖状導電性微粒子群が金属酸化物の場合、以下のようにして、調製することができる。
【0036】
まず、金属塩または金属アルコキシドが0.1〜5重量%の濃度で含まれるアルコール溶液を加熱して加水分解させる。このとき必要に応じて温水に加えたり、アルカリを加えもよい。このような加水分解によって、一次粒子径が1〜100nmの金属水酸化物のゲル分散液を調製する。次いで、ゲル分散液を濾別・洗浄し、空気中、200〜800℃の温度で焼成して導電性金属酸化物微粒子を調製する。
【0037】
ついで、この粉末を酸性またはアルカリ性の水および/またはアルコール溶媒に分散させて濃度10〜50重量%の分散液とし、必要に応じて有機安定剤の存在下でこの分散液を前記と同様にメカニカル分散処理する。必要に応じて前記同様にオートクレーブ処理を行ってもよい。
【0038】
(5)さらにまた、金属酸化物から構成される鎖状導電性微粒子群は、前記ゲル分散液を濾別・洗浄した後、必要に応じて有機安定剤の存在下で、金属水酸化物をオートクレーブ処理し、さらにメカニカル分散処理を行うことによって得ることができる。この場合、前記と同様にイオン交換樹脂処理して、イオン性不純物を除去してもよい。
【0039】
こうして得られた鎖状導電性微粒子群は、通常、遠心分離などの方法によって生成後の分散液から取り出され、必要に応じて酸などで洗浄されたのち、後述の極性溶媒に分散させて使用される。また、得られた鎖状導電性微粒子群を含む分散液は、そのまま塗布液として使用することもできる。
【0040】
透明導電性被膜形成用塗布液の調製
本発明に係る第1の透明導電性被膜形成用塗布液では、このような鎖状導電性微粒子群が、極性溶媒中に分散している。本発明で用いられる極性溶媒としては、水;メタノール、エタノール、プロパノール、ブタノール、ジアセトンアルコール、フルフリルアルコール、テトラヒドロフルフリルアルコール、エチレングリコール、ヘキシレングリコールなどのアルコール類;酢酸メチルエステル、酢酸エチルエステルなどのエステル類;ジエチルエーテル、エチレングリコールモノメチルエーテル、エチレングリコールモノエチルエーテル、エチレングリコールモノブチルエーテル、ジエチレングリコールモノメチルエーテル、ジエチレングリコールモノエチルエーテルなどのエーテル類;アセトン、メチルエチルケトン、アセチルアセトン、アセト酢酸エステルなどのケトン類などが挙げられる。これらは単独で使用してもよく、また2種以上混合して使用してもよい。
【0041】
また、本発明に係る透明導電性被膜形成用塗布液には、さらにマトリックス形成成分が含まれていてもよい。マトリックス形成成分は、本発明に係る透明導電性被膜形成用塗布液を用いて被膜する際に、導電性微粒子のバインダーとして作用する。このようなマトリックス形成成分としては、SiO2前駆体、TiO2前駆体、ZrO2前駆体または有機高分子から選ばれる少なくとも一種が好ましく使用され、このうち、特にSiO2前駆体、有機高分子が好ましい。SiO2前駆体として具体的には、アルコキシシランなどの有機ケイ素化合物を加水分解して得られる重縮合物あるいはアルカリ金属ケイ酸塩水溶液を脱アルカリして得られるケイ酸重縮合物などが挙げられる。また、有機高分子としては、ポリエチレン、ポリフェノール、エポキシ、ポリアミノ酸、ポリスチレンなどの塗料用樹脂が挙げられる。
【0042】
本発明に係る透明導電性被膜形成用塗布液中には、前記導電性微粒子が0.05〜5重量%、好ましくは0.1〜2重量%の濃度で含まれていることが望ましい。
【0043】
また、マトリックス形成成分は、前記鎖状導電性微粒子群1重量部当たり、0.01〜0.9重量部、好ましくは0.1〜0.5重量部の量で含まれていればよい。
【0044】
また、本発明に係る透明導電性被膜形成用塗布液には、導電性微粒子の分散性を向上させるため、有機系安定剤が含まれていてもよい。このような有機系安定剤として具体的には、ゼラチン、ポリビニルアルコール、ポリビニルピロリドン、ポリアクリル酸、エチレンジアミン四酢酸、シュウ酸、マロン酸、コハク酸、グルタール酸、アジピン酸、セバシン酸、マレイン酸、フマル酸、フタル酸、クエン酸などの多価カルボン酸およびその塩、セルロース誘導体、複素環化合物、界面活性剤あるいはこれらの混合物などが挙げられる。
【0045】
このような有機系安定剤は、導電性微粒子1重量部に対し、0.005〜0.5重量部、好ましくは0.01〜0.5重量部含まれていればよい。有機系安定剤の量が、0.005重量部未満の場合は充分な分散性が得られず、0.5重量部を超えて高い場合は導電性が阻害されることがある。
【0046】
さらにまた本発明に係る透明導電性被膜形成用塗布液には、塗布液の可視光の広い波長領域において可視光の透過率が一定になるように、染料、着色顔料あるいは着色粒子を含んでいてもよい。
【0047】
染料、着色顔料または着色粒子としては、公知のものを使用することが可能であり、具体的には、微粒子カーボン、ジアゾ系染料、チタンブラック、フタロシアニン系顔料、ジオキサジン顔料などが挙げられる。
【0048】
透明導電性被膜形成用塗布液中に、染料、着色顔料または着色粒子を含む場合、透明導電性被膜形成用塗布液中の固形分濃度(導電性微粒子と染料、顔料などの添加剤の総量)は、塗布液の流動性、塗布液中の導電性微粒子などの粒状成分の分散性などの点から、15重量%以下、好ましくは0.15〜5重量%の範囲にあることが望ましい。
【0049】
さらに本発明に係る透明導電性被膜形成用塗布液は、液中に存在するアルカリ金属イオン、アンモニウムイオンおよび多価金属イオンならびに鉱酸などの無機陰イオン、酢酸、蟻酸などの有機陰イオンなどのイオン濃度の合計量が、1000ppm以下であることが望ましい。特に鉱酸などの無機陰イオンは、鎖状導電性微粒子群の安定性、分散性を阻害することがあり、塗布液中の含有量はより少ない方が望ましい。イオン濃度が低くなると、透明導電性被膜形成用塗布液中に含まれている粒状成分、特に導電性微粒子の分散状態が良好となり、鎖状導電性微粒子群以外の単に凝集しただけの粒子をほとんど含まない塗布液が得られる。このような透明導電性被膜形成用塗布液中での鎖状導電性微粒子群の単分散状態は、透明導電性被膜の形成過程でも維持される。このため、イオン濃度の低い透明導電性被膜形成用塗布液から透明導電性被膜を形成すると、透明導電性被膜中には前記鎖状導電性微粒子群のみが観察される。
【0050】
また上記のようなイオン濃度の低い透明導電性被膜形成用塗布液を用いると、透明導電性被膜中で鎖状導電性微粒子群を良好に分散させ、均一に配列させることができるので、透明導電性被膜中で導電性微粒子が凝集している場合に比較して、より少ない導電性微粒子で同等の導電性を有する透明導電性被膜を提供することが可能となる。さらに鎖状導電性微粒子群同士の凝集に起因すると思われる点欠陥および厚さむらなどのない透明導電性被膜を基材上に形成することが可能である。
【0051】
このようなイオン濃度の低い透明導電性被膜形成用塗布液を得るための脱イオン処理の方法は、最終的に塗布液中に含まれているイオン濃度が上記のような範囲になるような方法であれば特に制限されないが、たとえば、鎖状導電性微粒子群を調製した分散液、または前記分散液から調製された塗布液を陽イオン交換樹脂および/または陰イオン交換樹脂あるいは両性イオン交換樹脂と接触させる方法、あるいはこれらの液を、限外濾過膜を用いて洗浄処理する方法などが挙げられる。
【0083】
[透明導電性被膜付基材]
次に、本発明に係る透明導電性被膜付基材について具体的に説明する。
本発明に係る透明導電性被膜付基材は、
基材と、基材上に設けられた透明導電性被膜と、該透明導電性被膜上に設けられた透明被膜とからなる。
【0084】
なお、本発明では、基材として公知のものを使用することが可能であり、具体的には、ガラス、プラスチック、セラミックなどからなるフィルム、シートあるいはその他の成形体などが挙げられる。
【0085】
透明導電性被膜
透明導電性被膜は、本発明に係る透明導電性被膜形成用塗布液を、基材上に塗布・乾燥して形成される。
【0086】
透明導電性被膜を形成する方法としては、たとえば、透明導電性被膜形成用塗布液をディッピング法、スピナー法、スプレー法、ロールコーター法、フレキソ印刷法などの方法で、基材上に塗布したのち、常温〜約90℃の範囲の温度で乾燥する。
【0087】
透明導電性被膜形成用塗布液中に上記のようなマトリックス形成成分が含まれている場合には、マトリックス形成成分の硬化処理を行ってもよい。
硬化処理としては、以下のような方法が挙げられる。
【0088】
▲1▼加熱硬化
乾燥後の塗膜を加熱して、マトリックス成分を硬化させる。このときの加熱処理温度は、100℃以上、好ましくは150〜300℃であることが望ましい。100℃未満ではマトリックス形成成分が充分硬化しないことがある。また加熱処理温度の上限は基材の種類によって異なるが、基材の転移点以下であればよい。
【0089】
▲2▼電磁波硬化
塗布工程または乾燥工程の後に、あるいは乾燥工程中に、塗膜に可視光線よりも波長の短い電磁波を照射して、マトリックス成分を硬化させる。このようなマトリックス形成成分の硬化を促進するために照射する電磁波としては、マトリックス形成成分の種類に応じて紫外線、電子線、X線、γ線などが用いられる。例えば紫外線硬化性マトリックス形成成分の硬化を促進するためには、例えば、発光強度が約250nmおよび360nmにおいて極大となり、光強度が10mW/m2以上である高圧水銀ランプを紫外線源として用い、100mJ/cm2以上のエネルギー量の紫外線が照射される。
【0090】
▲3▼ガス硬化
塗布工程または乾燥工程の後に、あるいは乾燥工程中に、塗膜をマトリックス形成成分の硬化反応を促進するガス雰囲気中に晒すことによって、マトリックス形成成分を硬化させる。マトリックス形成成分のなかには、アンモニアなどの活性ガスで硬化が促進されるマトリックス形成成分があり、このようなマトリックス形成成分を含む透明導電性被膜を、ガス濃度が100〜100000ppm、好ましくは1000〜10000ppmであるような硬化促進性ガス雰囲気下で1〜60分処理することによってマトリックス形成成分の硬化を大幅に促進することができる。
【0091】
上記のような方法によって形成された透明導電性被膜の膜厚は、約50〜200nm、好ましくは10〜150nmの範囲が好ましく、この範囲の膜厚であれば電磁遮蔽効果に優れた透明導電性被膜付基材を得ることができる。
透明被膜
本発明に係る透明導電性被膜付基材では、このような透明導電性被膜の上に、前記透明導電性被膜よりも屈折率の低い透明被膜が形成されている。
【0092】
形成される透明被膜の膜厚は、50〜300nm、好ましくは80〜200nmの範囲にあることが好ましい。
このような透明被膜は、たとえば、シリカ、チタニア、ジルコニアなどの無機酸化物、およびこれらの複合酸化物などから形成される。本発明では、透明被膜として、特に加水分解性有機ケイ素化合物の加水分解重縮合物、またはアルカリ金属ケイ酸塩水溶液を脱アルカリして得られるケイ酸重縮合物からなるシリカ系被膜が好ましい。このような透明被膜が形成された透明導電性被膜付基材は、反射防止性能に優れている。
【0093】
また、上記透明被膜中には、必要に応じて、フッ化マグネシウムなどの低屈折率材料で構成された微粒子などの添加剤が含まれていてもよい。
本発明では、上記のようにして形成された透明導電性被膜の上に、該微粒子層よりも屈折率の低い透明被膜が形成されている。
【0094】
透明被膜の膜厚は、50〜300nm、好ましくは80〜200nmの範囲であることが好ましく、このような範囲の膜厚であると優れた反射防止性を発揮する。透明被膜の形成方法としては、特に制限はなく、この透明被膜の材質に応じて、真空蒸発法、スパッタリング法、イオンプレーティング法などの乾式薄膜形成方法、あるいは上述したようなディッピング法、スピナー法、スプレー法、ロールコーター法、フレキソ印刷法などの湿式薄膜形成方法を採用することができる。
【0095】
上記透明被膜を湿式薄膜形成方法で形成する場合、従来公知の透明被膜形成用塗布液、たとえばシリカ、チタニア、ジルコニアなどの無機酸化物前駆体、またはこれらの複合酸化物前駆体を透明被膜形成成分として含む透明被膜形成用塗布液を用いることが可能である。
【0096】
本発明では、透明被膜形成用塗布液として、加水分解性有機ケイ素化合物の加水分解重縮合物、またはアルカリ金属ケイ酸塩水溶液を脱アルカリして得られるケイ酸を含むシリカ系透明被膜形成用塗布液が好ましく、特に下記一般式[1]で表されるアルコキシシランの加水分解重縮合物を含有しているシリカ系透明被膜形成用塗布液が好ましい。このような塗布液から形成されるシリカ系被膜は、前記透明導電性被膜よりも屈折率が小さく、得られる透明被膜付基材は反射防止性に優れている。
【0097】
aSi(OR')4-a [1]
(式中、Rはビニル基、アリール基、アクリル基、炭素数1〜8のアルキル基、水素原子またはハロゲン原子であり、R'はビニル基、アリール基、アクリル基、炭素数1〜8のアルキル基、−C24OCn2n+1 (n=1〜4)または水素原子であり、aは1〜3の整数である。)
このようなアルコキシランとしては、テトラメトキシシラン、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、テトラオクチルシラン、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、メチルトリイソプロポキシシラン、ビニルトリメトキシシラン、フェニルトリメトキシシラン、ジメチルジメトキシシランなどが挙げられる。
【0098】
上記のアルコキシシランの1種または2種以上を、たとえば水−アルコール混合溶媒中で酸触媒の存在下で加水分解すると、アルコキシシランの加水分解重縮合物を含む透明被膜形成用塗布液が得られる。このような塗布液中に含まれる被膜形成成分の濃度は、酸化物換算で0.5〜20重量%であることが好ましい。
【0099】
本発明で使用される透明被膜形成用塗布液は、前記した本発明に係る透明導電性被膜形成用塗布液の場合と同様に、脱イオン処理を行い、透明導電性塗布液のイオン濃度を前記透明導電性被膜形成用塗布液中の濃度と同じレベルまで低減させてもよい。
【0100】
さらにまた、本発明で使用される透明被膜形成用塗布液には、フッ化マグネシウムなどの低屈折率材料で構成された微粒子、透明被膜の透明度および反射防止性能を阻害しない程度に少量の導電性微粒子、染料、着色顔料、微粒子カーボンなどの添加剤が含まれていてもよい。
【0101】
本発明では、このような透明被膜形成用塗布液を塗布して形成した被膜を、150℃以上の温度で乾燥したり、乾燥後に150℃以上で加熱したり、未硬化の被膜に可視光線よりも波長の短い紫外線、電子線、X線、γ線などの電磁波を照射したり、アンモニアなどの活性ガス雰囲気中に晒すなどの処理を施してもよい。このように処理を行うと、被膜形成成分の硬化が促進され、得られる透明被膜の硬度を高くすることができる。また、上記硬化処理を行う場合、透明被膜形成用塗布液を塗布する際に、透明導電性被膜を約40〜90℃に保持しながら透明被膜形成用塗布液を塗布することが好ましい。透明導電性被膜を約40〜90℃に保持しながら、該透明導電性被膜上に、透明被膜形成用塗布液を塗布することによって、透明被膜の表面にリング状の凹凸が形成され、ギラツキの少ないアンチグレアの透明被膜付基材を得ることができる。
【0102】
[表示装置]
本発明に係る透明導電性被膜付基材は、電磁遮蔽に必要な102〜104Ω/□の範囲の表面抵抗を有し、かつ可視光領域および近赤外領域で充分な反射防止性能と防眩性を有する透明導電性被膜付基材は、表示装置の前面板として好適に用いられる。
【0103】
本発明に係る表示装置は、ブラウン管(CRT)、蛍光表示管(FIP)、プラズマディスプレイ(PDP)、液晶用ディスプレイ(LCD)などのような電気的に画像を表示する装置であり、上記のような透明導電性被膜付基材で構成された前面板を備えている。
【0104】
従来の前面板を備えた表示装置を作動させると、前面板に画像が表示されると同時に電磁波が前面板から放出され、この電磁波が観察者の人体に影響を及ぼすが、本発明に係る表示装置では、前面板が102〜104Ω/□の表面抵抗を有する透明導電性被膜付基材で構成されているので、このような電磁波、およびこの電磁波の放出に伴って生じる電磁場を効果的に遮蔽することができる。
【0105】
また、表示装置の前面板で反射光が生じると、この反射光によって表示画像が見にくくなるが、本発明に係る表示装置では、前面板が可視光領域および近赤外領域で充分な反射防止性能および防眩性を有する透明導電性被膜付基材で構成されているので、このような反射光を効果的に防止することができる。
【0106】
さらに、ブラウン管の前面板が、本発明に係る透明導電性被膜付基材で構成され、この透明導電性被膜のうち、透明導電性被膜、その上に形成された透明被膜の少なくとも一方に少量の染料または顔料が含まれている場合には、これらの染料または顔料がそれぞれ固有な波長の光を吸収し、これによりブラウン管から放映される表示画像のコントラストを向上させることができる。
【0107】
【発明の効果】
本発明によれば、導電性、電磁遮蔽性に優れるとともに、光透過率の制御が可能であり、反射防止性能および防眩性を有し、信頼性が高い透明導電性被膜を形成しうる透明導電性被膜形成用塗布液を得ることができる。
【0108】
また、本発明によれば、導電性、電磁遮蔽性に優れるとともに、光透過率の制御が可能であり、反射防止性能および防眩性を有し、信頼性が高い透明導電性被膜が形成された透明導電性被膜付基材を得ることができる。
【0109】
このような透明導電性被膜付基材を表示装置の前面板として用いれば、電磁遮蔽性に優れるとともに反射防止性および防眩性にも優れた表示装置を得ることができる。
【0110】
【実施例】
以下、本発明を実施例により説明するが、本発明はこれら実施例に限定されるものではない。
【0111】
【製造実施例】
a)導電性微粒子分散液の調製
本実施例および比較例で用いた導電性微粒子分散液組成を表1に示す。
【0112】
鎖状導電性微粒子群 (P-1)
まず、純水100gに、あらかじめ金属換算で濃度が10重量%となり、複合金属の金属種が表1の重量比となるように硝酸銀および硝酸パラジウム水溶液を加えた水溶液を調製した。この水溶液に、複合金属1重量部あたり、0.01重量部となるような量でクエン酸3ナトリウム(有機安定化剤および還元剤)を含む水溶液と、硝酸銀および硝酸パラジウムの合計モル数と等モル数の硫酸第一鉄(還元剤)水溶液とを混合した混合溶液を加え、窒素雰囲気下で1時間撹拌して複合金属微粒子の分散液を得た。
【0113】
得られた分散液は遠心分離機により分離した後、濃度1重量%のHClで酸洗浄して、ポリアクリル酸を複合金属1重量部当たり0.0128重量部となるように加え純水に分散させて表1に示す濃度の分散液を調製した。ついで、得られた分散液をナノマイザーシステム(ナノマイザー(株):LA-33-S)にて処理して、鎖状導電性微粒子群(P-1)の分散液を得た。
【0114】
鎖状導電性微粒子群 (P-2)
純水100gに、あらかじめ塩化白金酸を加え、これに金属換算で濃度が10重量%となり、複合金属の金属種が表1の重量比となるように酢酸パラジウムのアセトン溶液を加えたのち、さらに塩化白金酸および酢酸パラジウムの合計モル数と等モル数のクエン酸3ナトリウムを添加し、窒素雰囲気下で1時間撹拌して複合金属微粒子の分散液を得た。
【0115】
得られた分散液は遠心分離機により分離した後、濃度1重量%のHClで酸洗浄して、ポリアクリル酸を複合金属1重量部当たり0.0128重量部となるように加え純水に分散させて表1に示す濃度の分散液を調製した。ついで、得られた分散液をナノマイザーシステム処理して、鎖状導電性微粒子群(P-2)の分散液を得た。
【0116】
鎖状導電性微粒子群 (P-3)
前記調製した導電性微粒子(P-1)の分散液を、オートクレーブ中、窒素雰囲気下、150℃、 10.0Kg/cm2で1時間撹拌した後、前記ナノマイザーシステムを用いて処理を行い、鎖状導電性微粒子群(P-3)の分散液を得た。
【0117】
鎖状導電性微粒子群 (P-4)
前記調製した導電性微粒子(P-1)の分散液に、複合金属の金属種が表1の重量比となるように硝酸銀水溶液を加え、硝酸銀と等モル数の硫酸第一鉄水溶液を添加し、窒素雰囲気下で1時間撹拌して複合金属微粒子の分散液を得た。得られた分散液は遠心分離機により分離した後、水洗浄して純水に分散させて表1に示す濃度の分散液を調製した。ついで、得られた分散液をナノマイザーシステムにて処理を行い、鎖状導電性微粒子群(P-4)の分散液を得た。
【0118】
棒状導電性微粒子群 (P-5)
純水100gに、鎖状無機酸化物として、平均長さが50nm、断面の平均径が10nmの繊維状アルミナ微粒子を表1の重量比となるようにあらかじめ加え、これに複合金属の金属種が表1の重量比となるように硝酸銀および硝酸パラジウム水溶液を加えた水溶液を調製した。この水溶液に、複合金属1重量部あたり、0.01重量部となるような量でクエン酸3ナトリウム(有機安定化剤および還元剤)を含む水溶液と、金属換算で濃度が10重量%となり、硝酸銀および硝酸パラジウムの合計モル数と等モル数の硫酸第一鉄(還元剤)水溶液とを混合した混合溶液を加え、窒素雰囲気下で1時間撹拌して複合金属微粒子の分散液を得た。
【0119】
得られた分散液は遠心分離機により分離した後、濃度1重量%のHClで酸洗浄して、ポリアクリル酸を複合金属1重量部当たり0.0128重量部となるように加え純水に分散させて表1に示す濃度の分散液を調製した。ついで、得られた分散液をナノマイザーシステム(ナノマイザー(株):LA-33-S)にて処理して、棒状導電性微粒子群(P-5)の分散液を得た。
【0120】
棒状導電性微粒子群 (P-6)
前記導電性微粒子(P-5)で使用した繊維状アルミナ微粒子の分散液に、複合金属微粒子(P-1)の分散液を表1の重量比となるように混合し、ナノマイザーシステムを使用して行い、棒状複合金属微粒子群(P-6)の分散液を得た。
【0122】
単分散導電性微粒子 (P-8)
純水100gに、あらかじめ金属換算で濃度が10重量%となり、複合金属の金属種が表1の重量比となるように硝酸銀および硝酸パラジウム水溶液を加えた水溶液を調製した。この水溶液に、複合金属1重量部あたり、0.01重量部となるような量でクエン酸3ナトリウム(有機安定化剤および還元剤)を含む水溶液と、硝酸銀および硝酸パラジウムの合計モル数と等モル数の硫酸第一鉄(還元剤)水溶液とを混合した混合溶液を加え、窒素雰囲気下で1時間撹拌して複合金属微粒子の分散液を得た。
【0123】
得られた分散液は遠心分離機により分離した後、水洗浄して、純水に分散させて表1に示す濃度の単分散導電性微粒子(P-8)を調製した。
導電性微粒子 (P-9)
純水100gに、あらかじめ金属換算で濃度が10重量%となり、複合金属の金属種が表1の重量比となるように硝酸銀および硝酸パラジウム水溶液を加えた水溶液を調製した。この水溶液に、複合金属1重量部あたり、0.01重量部となるような量でクエン酸3ナトリウム(有機安定化剤および還元剤)を含む水溶液と、硝酸銀および硝酸パラジウムの合計モル数に対し3倍モル数の硫酸第一鉄(還元剤)水溶液とを混合した混合溶液を加え、窒素雰囲気下で1時間撹拌して複合金属微粒子の分散液を得た。得られた分散液は遠心分離機により分離した後、濃度1重量%のHClで酸洗浄して、ポリアクリル酸を複合金属1重量部当たり0.0128重量部となるように加え純水に分散させて表1に示す濃度の分散液を調製した。次いで、得られた分散液をナノマイザーにて粉砕して、複合金属微粒子(P-9)の分散液を得た。得られた複合金属微粒子(P-9)の形状は、鎖状導電性微粒子群であった。
【0124】
導電性微粒子 (P-10)
純水100gに、あらかじめ金属換算で濃度が10重量%となり、複合金属の金属種が表1の重量比となるように硝酸銀および硝酸パラジウム水溶液を加えた水溶液を調製した。この水溶液に、複合金属1重量部あたり、0.01重量部となるような量でクエン酸3ナトリウム(有機安定化剤および還元剤)を含む水溶液と、硝酸銀および硝酸パラジウムの合計モル数に対し、3倍モル数の硫酸第一鉄(還元剤)水溶液とを混合した混合溶液を加え、窒素雰囲気下で1時間撹拌して複合金属微粒子の分散液を得た。得られた分散液は、遠心分離機により分離した後、濃度1重量%のHClで酸洗浄して、ポリアクリル酸を複合金属1重量部当たり0.03重量部となるように加え純水に分散させて表1に示す濃度の分散液を調製した。次いで、得られた分散液をナノマイザーにて粉砕して、複合金属微粒子(P-10)の分散液を得た。得られた複合金属微粒子(P-10)の形状は、鎖状導電性微粒子群であった。
【0125】
導電性微粒子( P-11
純水100gに、あらかじめ金属換算で濃度が10重量%となり、複合金属の金属種が表1の重量比となるように硝酸銀および硝酸パラジウム水溶液を加えた水溶液を調製した。この水溶液に、複合金属1重量部あたり、0.01重量部となるような量でクエン酸3ナトリウム(有機安定化剤および還元剤)を含む水溶液と、硝酸銀および硝酸パラジウムの合計モル数に対し3倍モル数の硫酸第一鉄(還元剤)水溶液とを混合した混合溶液を加え、窒素雰囲気下で1時間撹拌して複合金属微粒子の分散液を得た。得られた分散液は、遠心分離機により分離した後、濃度1重量%のHClで酸洗浄して、ポリアクリル酸を複合金属1重量部当たり0.20重量部となるように加え純水に分散させて表1に示す濃度の分散液を調製した。次いで、得られた分散液をナノマイザーにて粉砕して、複合金属微粒子(P-11)の分散液を得た。得られた複合金属微粒子(P-11)は凝集粒子であった。
【0126】
導電性酸化物微粒子( P-12
純水100gに、あらかじめ硝酸インジウムおよびフッ素化スズを金属換算で10重量%となり、複合金属の金属種が表1の重量比になるように加え、これに10重量%の水酸化カリウムを加えて、複合金属粒子の沈殿を作製した。この複合金属粒子の沈殿を水洗したのち、金属換算で10重量%となるように純水を加え、これに純水およびアセチルアセトン(有機分散剤)を加え、サンドミルおよびナノマイザーシステムにて処理して、単分散複合金属微粒子(P-12)の分散液を得た。
【0127】
導電性カーボン微粒子 (P-13)
純水100gに、着色剤として導電性カーボン微粒子(三菱化学(株)製:MA-100)を表1の濃度になるように加えて導電性微粒子(P-13)分散液を調製した。
【0128】
なお、本発明の導電性微粒子の一次粒子、鎖状および棒状の観察、粒子径、粒子長さなどの測定は、走査型電子顕微鏡(日本電子(株):JMS5300)を用いて100個の粒子について観察した。
【0129】
また、アスペクト比は、粒子長さをLとし、一次粒子径を粒子の断面径Dとし、L/Dで表した。なお、鎖状導電性微粒子群のアスペクト比は、粒子長さをLとし、一次粒子径を粒子の断面径Dとした。
【0130】
【表1】

Figure 0004522505
【0131】
b)マトリックス形成成分液 ( ) の調製
正珪酸エチル(SiO2:28重量%)50g、エタノール194.6g、濃硝 酸1.4gおよび純水34gの混合溶液を室温で5時間撹拌してSiO2濃度5重量%のマトリックス形成成分を含む液(M)を調製した。
【0132】
c)透明導電性被膜形成用塗布液の調製
表1に示す(P-1)〜(P-13)の分散液と、上記マトリックス形成成分を含む(A)液、水、t-ブタノール、ブチルセルソルブ、クエン酸およびN-メチル-2-ピロリド ンを用いて、表2に示す透明導電性被膜形成用塗布液(C-1)〜(C-14)を調製した。
【0133】
【表2】
Figure 0004522505
【0134】
d)透明被膜形成用塗布液 (B-1) の調製
上記マトリックス形成成分を含む(A)液に、エタノール/ブタノール/ジアセ トンアルコール/イソプロパノール(2:1:1:5重量混合比)の混合溶媒を加え、SiO2濃度1重量%の透明被膜形成用塗布液(B-1)を調製した。
【0135】
なお、本発明で使用される導電性被膜形成用塗布液および透明被膜形成用塗布液は両性イオン交換樹脂(三菱化学(株)製 ダイヤイオン SMNUPB)で脱イオン処理することにより、各塗布液中のイオン濃度の調製を行った。
【0136】
また、塗布液中のアルカリ金属イオン濃度およびアルカリ土類金属イオン濃度は原子吸光法で測定し、その他の金属イオン濃度は発光分光分析法で測定し、アンモニウムイオンおよびアニオンのイオン濃度はイオンクロマトグラフィー法で測定した。
【0137】
【実施例1〜9】
透明導電性被膜付パネルガラスの製造
ブラウン管用パネルガラス(14")の表面を40℃で保持しながら、スピナー 法で100rpm、90秒の条件で上記透明導電性被膜形成用塗布液(C-1)〜(C-9)をそれぞれ塗布し乾燥した。
【0138】
次いで、このようにして形成された透明導電性被膜上に、同じように、スピナー法で100rpm、90秒の条件で透明被膜形成用塗布液(B-1)を塗布・乾燥し、表3に示す条件で焼成して透明導電性被膜付基材を得た。
【0139】
これらの透明導電性被膜付基材の表面抵抗を表面抵抗計(三菱油化(株)製:LORESTA)で測定し、ヘーズをへーズコンピューター(日本電色(株)製:3000A)で測定した。反射率は反射率計(大塚電子(株)製:MCPD-2000)を用いて測定し、波長400〜700nmの範囲で反射率が最も低い波長での反射率とした。
【0140】
結果を表3に示す。
【0141】
【比較例1〜5】
透明導電性被膜付パネルガラスの製造
ブラウン管用パネルガラス(14")の表面を40℃で保持しながら、スピナー 法で100rpm、90秒の条件で上記透明導電性被膜形成用塗布液(C-10)〜(C-14)をそれぞれ塗布し乾燥した。
【0142】
次いで、このようにして形成された透明導電性被膜上に、同じように、スピナー法で100rpm、90秒の条件で透明被膜形成用塗布液(B-1)を塗布・乾燥し、表3に示す条件で焼成して透明導電性被膜付基材を得た。
【0143】
これらの透明導電性被膜付基材の表面抵抗を表面抵抗計(三菱油化(株)製:LORESTA)で測定し、ヘーズをへーズコンピューター(日本電色(株)製:3000A)で測定した。反射率は反射率計(大塚電子(株)製:MCPD-2000)を用いて測定し、波長400〜700nmの範囲で反射率が最も低い波長での反射率とした。
【0144】
結果を表3に示す
【0145】
【表3】
Figure 0004522505

【図面の簡単な説明】
【図1】本発明に係る透明導電性被膜形成用塗布液中に含まれている鎖状導電性微粒子群の一態様を示す概略図である。
【図2】本発明に係る透明導電性被膜形成用塗布液中に含まれている鎖状導電性微粒子群の別の一態様を示す概略図である。
【図3】本発明に係る透明導電性被膜形成用塗布液中に含まれている鎖状導電性微粒子群の別の一態様を示す概略図である。
【図4】本発明に係る透明導電性被膜形成用塗布液中に含まれている棒状導電性微粒子の一態様を示す概略図である。
【図5】本発明に係る透明導電性被膜形成用塗布液中に含まれている棒状導電性微粒子の別の一態様を示す概略図である。
【図6】本発明に係る透明導電性被膜形成用塗布液中に含まれている棒状導電性微粒子群の一態様を示す概略図である。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a coating liquid for forming a transparent conductive film, a substrate with a transparent conductive film, and a display device including the substrate as a front plate, and more specifically, antistatic properties, electromagnetic shielding properties, transparency, and reflection. Composition comprising a coating liquid capable of forming a substrate with a transparent conductive film excellent in prevention properties, the substrate with a transparent conductive film obtained using the coating liquid, and the substrate with a transparent conductive film The present invention relates to a display device including a front plate.
[0002]
TECHNICAL BACKGROUND OF THE INVENTION
Conventionally, transparent coatings having an antistatic function and an antireflection function on the surfaces thereof for the purpose of antistatic and antireflection of the surfaces of transparent substrates of display panels such as cathode ray tubes, fluorescent display tubes, liquid crystal display panels, etc. It was done to form.
[0003]
By the way, the influence of electromagnetic waves emitted from cathode ray tubes, etc. on the human body has recently become a problem, and in addition to conventional antistatic and antireflection, these electromagnetic waves and electromagnetic fields formed with the emission of electromagnetic waves are shielded. It is hoped to do.
[0004]
One method of shielding these electromagnetic waves and the like is a method of forming a conductive film for shielding electromagnetic waves on the surface of a display panel such as a cathode ray tube. However, the conventional antistatic conductive coating has a surface resistance of at least 107While it is sufficient to have a surface resistance of about Ω / □, it is 10 for a conductive coating for electromagnetic shielding.2-10FourIt was necessary to have a low surface resistance such as Ω / □.
[0005]
When such a conductive film having a low surface resistance is formed by using a coating liquid containing a conductive oxide such as Sb-doped tin oxide and Sn-doped indium oxide, which has been conventionally used, It was necessary to make the film thickness thicker than the case. However, since the antireflection effect is not exhibited unless the film thickness of the conductive film is about 10 to 200 nm, conventional conductive oxides such as Sb-doped tin oxide and Sn-doped indium oxide have low surface resistance, and electromagnetic waves. There was a problem that it was difficult to obtain a conductive film that was excellent in blocking properties and also excellent in antireflection.
[0006]
Further, as one method for forming a conductive film having a low surface resistance, there is a method of forming a metal fine particle-containing film on the surface of a substrate using a coating liquid for forming a conductive film containing metal fine particles such as Ag. . In this method, a coating solution in which colloidal metal fine particles are dispersed in a polar solvent is used as a coating solution for forming a coating containing metal fine particles. In such a coating solution, in order to improve the dispersibility of the colloidal metal fine particles, the surface of the metal fine particles is surface-treated with an organic stabilizer such as polyvinyl alcohol, polyvinyl pyrrolidone or gelatin. However, a conductive coating formed using such a coating solution for forming a coating containing metal fine particles has a large intergranular resistance because the metal fine particles come into contact with each other through a stabilizer in the coating. Sometimes did not go down. For this reason, it is necessary to decompose and remove the stabilizer by baking at a high temperature of about 400 ° C. after film formation. However, if the baking is performed at a high temperature to decompose and remove the stabilizer, fusion and aggregation of metal fine particles occur. There has been a problem that the transparency and haze of the conductive film are lowered. In the case of a cathode ray tube or the like, there is a problem that the cathode ray tube deteriorates when exposed to a high temperature.
[0007]
Furthermore, in the conventional transparent conductive film containing fine metal particles such as Ag, the metal may be oxidized, particle growth may occur due to ionization, and corrosion may occur in some cases. As a result, there was a problem that the display device lacked reliability.
[0008]
In addition, since monodispersed fine particles are used in the conventional transparent conductive film, a sufficiently low resistance film can be obtained due to the influence of the matrix, the organic stabilizer remaining on the particle surface, the solvent, or the grain boundary resistance. If not, sufficient reproducibility may not be obtained. For this reason, for example, when the film thickness is increased in order to reduce the resistance of the film, there is a problem that transparency is lowered.
[0009]
OBJECT OF THE INVENTION
The present invention has been made to solve the above-mentioned problems of the prior art.2-10FourTransparent conductivity that has a low surface resistance of about Ω / □, and can form a transparent conductive film with excellent antistatic properties, transparency, antireflection properties, antiglare properties, and electromagnetic shielding properties, as well as excellent reliability. An object of the present invention is to provide a coating liquid for forming a conductive film, a substrate with a transparent conductive film, and a display device including the substrate as a front plate.
[0010]
SUMMARY OF THE INVENTION
The first transparent conductive film-forming coating solution according to the present invention is:
In a coating liquid for forming a transparent conductive film containing conductive fine particles and a polar solvent,
The conductive fine particles are characterized by comprising a chain conductive fine particle group having a chain structure in which two or more primary particles having an average particle diameter in the range of 1 to 100 nm are continuously joined in a chain shape.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be specifically described.
[First coating liquid for forming transparent conductive film]
First, the first coating liquid for forming a transparent conductive film according to the present invention will be described.
[0014]
The coating liquid for forming a transparent conductive film according to the present invention includes a chain conductive fine particle group and a polar solvent.
Chain of conductive fine particles
The “chain conductive fine particle group” as used in the present invention is an average particle diameter of 1 to 100 nm, preferably 5 to 80 nm, as shown in FIG. A fine particle having a chain structure.
[0015]
Such a chain conductive fine particle group is different from the case where primary particles are simply aggregated by interparticle attractive force or the like. Bonded through oxygen. Further, as shown in FIG. 2, the same or different components as the primary particles may be bonded to the contact portions of the particles called “neck”, and the primary particles may be bonded to each other in a plane. Such a chain-like conductive fine particle group may be linear, zigzag, or curved in an arc. Furthermore, as shown in FIG. 3, the ring-shaped conductive fine particle group may have a ring shape in which the ends are joined to each other.
[0016]
Since there is no intergranular resistance between the primary particles constituting such a chain conductive fine particle group, and neither an organic stabilizer nor a solvent can be present, a coating liquid containing the chain conductive fine particle group is applied. The resistance of the resulting film is reduced and a low resistance film is obtained.
[0017]
If the average primary particle size of the conductive fine particles exceeds 100 nm, it becomes difficult to form a chain conductive fine particle group, and even if it can be made, the number of contact points of the particles in the conductive layer is reduced, so that it has a low resistance value. It becomes difficult to obtain a conductive film. Furthermore, if the average primary particle size exceeds 100 nm, light absorption by the conductive fine particles increases, and the light transmittance of the coating may decrease or the haze of the coating may increase. If a coated substrate containing conductive fine particles having a thickness exceeding 100 nm is used, for example, as the front plate of a cathode ray tube, the brightness of the displayed image becomes insufficient, and thus the film thickness is reduced to obtain a certain transmittance. If the amount of the conductive fine particles is reduced, sufficient conductivity may not be obtained.
[0018]
In addition, when the average particle diameter of the conductive fine particles is less than 1 nm, the grain boundary resistance increases rapidly, so that a transparent conductive film having a low resistance value that can achieve the object of the present invention cannot be obtained. Sometimes. In addition, since the particles are small, the chain-like conductive fine particle group cannot be obtained, and the three-dimensionally aggregated particles tend to increase, and a conductive film having a low resistance value may not be obtained.
[0019]
The average length of such chain conductive fine particle groups is in the range of 2 to 200 nm, preferably 5 to 80 nm.
If the average length is less than 2 nm, the contact resistance increases and a low-resistance transparent conductive film may not be obtained. If the average length exceeds 200 nm, the formability of the transparent conductive film decreases, There is a problem in optical characteristics such as haze, and the appearance is further deteriorated.
[0020]
In the present invention, all the conductive fine particles may form the chain conductive fine particle group as described above, but at least a part of the conductive fine particles may form the chain conductive fine particle group. . In this case, the proportion of the chain conductive fine particle group is desirably contained in the conductive fine particles in an amount of 5% or more. When the proportion of the chain conductive fine particle group is less than 5%, the effect of reducing the resistance may be insufficient.
[0021]
Such a chain conductive fine particle group includes Au, Ag, Pd, Cu, Ni, Ru, Rh, Sn, In, Sb, Fe, Pt, Ti, Cr, Co, Al, Zn, Ta, Pb, Os. , Ir and a metal and / or metal hydroxide or metal oxide of one or more elements selected from the group consisting of different metal-doped metal oxides and mixtures thereof.
[0022]
In the case where the chain conductive fine particle group is a metal fine particle composed of two or more kinds of elements, preferred metal combinations include Au-Cu, Ag-Pt, Ag-Pd, Au-Pd, Au-Rh, and Pt-Pd. , Pt-Rh, Fe-Ni, Ni-Pd, Fe-Co, Cu-Co, Ru-Ag, Au-Cu-Ag, Ag-Cu-Pt, Ag-Cu-Pd, Ag-Au-Pd, Au -Rh-Pd, Ag-Pt-Pd, Ag-Pt-Rh, Fe-Ni-Pd, Fe-Co-Pd, Cu-Co-Pd and the like. The two or more kinds of metals constituting the chain conductive fine particle group may be an alloy in a solid solution state or a eutectic body not in a solid solution state, and the alloy and the eutectic body coexist. May be. When the chain-like conductive fine particle group is composed of two or more kinds of metals, metal oxidation, ionization, or ion migration is suppressed, so that particle growth of the conductive fine particles after the coating is formed is suppressed. In addition, the chain conductive fine particle group composed of two or more kinds of metals has high corrosion resistance, and the decrease in conductivity and light transmittance is small, so that a transparent conductive film excellent in reliability should be formed. Can do.
[0023]
Preferred examples of the case where the conductive fine particles are a metal oxide or a different metal doped metal oxide include, for example, tin oxide, indium oxide, Sn or F doped with tin oxide, Sb, F or P. Examples thereof include indium oxide, antimony oxide, and low-order titanium oxide.
[0024]
Such a chain conductive fine particle group is preferably obtained by subjecting a metal fine particle dispersed slurry or a metal hydroxide gel slurry to a heat treatment followed by a mechanical dispersion treatment.
[0025]
Specifically, the chain conductive fine particle group is prepared by the following method.
(1) For example, in the case of a chain-like conductive fine particle group made of metal, it can be obtained by the following method.
[0026]
First, metal salt is reduced in an alcohol / water mixed solvent to prepare a metal fine particle-dispersed slurry having a primary particle size of 1 to 100 nm. At this time, a reducing agent is usually added. As the reducing agent, ferrous sulfate, trisodium citrate, tartaric acid, sodium borohydride, hydrazine, sodium hypophosphite and the like are used. In addition, when using 2 or more types of metal salts, 2 or more types of metal salts may be reduce | restored simultaneously, and after reducing each metal salt, you may mix.
[0027]
It is desirable to remove ionic impurities from the obtained metal fine particle dispersed slurry. The method for removing ionic impurities is not particularly limited, and examples thereof include a method of treating with a cationic, anionic or amphoteric ion exchange resin. Although the ionic impurities vary depending on the amount of conductive fine particles in the coating solution, it is desirable that the ionic impurity has an ion concentration of 1000 ppm or less in the coating solution. If the amount of ionic impurities is 1000 ppm or less, the coating solution can have a high stability (long pot life), and moreover, the conductive fine particles are less likely to aggregate during the formation of the film, so that a smooth film can be formed. Can be formed.
[0028]
Next, the obtained metal fine particle dispersed slurry can be subjected to mechanical dispersion treatment. By this mechanical dispersion treatment, a sol in which the generated gel is peptized and the chain conductive fine particles are dispersed is obtained. Examples of such mechanical dispersion treatment include a sand mill method and an impact dispersion method, and the impact dispersion method is particularly preferably used. The impact dispersion method is a method in which slurry is collided with a wall at a high speed such as the speed of sound to be dispersed or pulverized, and is performed using an apparatus such as an Artimizer or Nanomizer, for example. In such a method, the bonds in the particles are not cut and the crystallinity is made amorphous, and the conductivity due to the generation of surface functional groups such as OH groups is not reduced, and the stably dispersed chain conductive material Since a fine particle group-dispersed sol is obtained, it is preferable.
[0029]
In addition, when performing a mechanical dispersion process, you may add a stabilizer. Specific examples of stabilizers include gelatin, polyvinyl alcohol, polyvinyl pyrrolidone, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, sebacic acid, maleic acid, fumaric acid, phthalic acid, and citric acid. Examples thereof include acids and salts thereof, heterocyclic compounds, and mixtures thereof. The stabilizer used in the preparation of the conductive fine particles may be the same as or different from the stabilizer added to the coating solution described later, and the amount of stabilizer used is the CMC (critical micelle formation) of the stabilizer. It is desirable that the concentration is in the range of 5 to 50%, preferably 5 to 30%.
[0030]
If the amount of the stabilizer is less than 5% of the CMC, the amount of the stabilizer on the particle surface is small, so that non-chain particles linked in three dimensions may be formed, and the amount of the stabilizer is 50% of the CMC. If it exceeds, monodispersed particles increase without generating chain conductive fine particle groups, and the effect of lowering the resistance of the conductive layer due to the formation of conductive paths in the chain conductive fine particle groups may not be obtained.
[0031]
(2) In addition to the above, the chain conductive fine particle group composed of metal can be prepared by the following method.
First, in the same manner as described above, a metal salt is reduced in an alcohol / water mixed solvent to prepare a metal fine particle-dispersed slurry having a primary particle size of 1 to 100 nm. At this time, a reducing agent is usually added. Examples of the reducing agent include the same as described above.
[0032]
Next, the prepared metal fine particle-dispersed slurry is subjected to heat treatment under pressure using a pressure vessel or the like (hereinafter, this treatment is referred to as autoclave treatment). Such autoclave treatment is usually performed at a temperature of about 100 to 250 ° C. At this time, a stabilizer may be added, and the kind and amount of the stabilizer are the same as described above. Further, when this heat treatment is performed, the generation rate of the chain conductive fine particle group and the length of the chain conductive fine particle group can be controlled by the presence or absence of stirring of the metal fine particle dispersed slurry.
[0033]
After the autoclave treatment, the mechanical dispersion treatment as described above is performed.
Moreover, when performing an autoclave process, you may add a metal salt further. The metal salt used may be the same as or different from that used when preparing the metal fine particle dispersed slurry. When such a metal salt is added, the metal ion migrates to the neck portion during the heat treatment, and the particle bonding is changed from the point bonding to the surface bonding, and has a “neck” portion as shown in FIG. A group of chain conductive fine particles is obtained.
[0034]
(3) Furthermore, the chain-like conductive fine particle group composed of a metal can be prepared by the following method.
First, a metal salt is reduced in an alcohol / water mixed solvent in the presence of a reducing agent and an organic stabilizer. At this time, examples of the reducing agent and the organic stabilizer used are the same as those described above. The organic stabilizer may be contained in an amount of 0.005 to 0.5 parts by weight, preferably 0.01 to 0.2 parts by weight with respect to 1 part by weight of the generated metal fine particles. When the amount of the organic stabilizer is less than 0.005 parts by weight, sufficient dispersibility cannot be obtained, and when it exceeds 0.5 parts by weight, the amount of chain conductive fine particles is small and monodisperse particles are formed. In the presence of an excess of organic stabilizer, aggregated particles may be formed, and the conductivity may be hindered by the remaining organic stabilizer.
[0035]
Even in this method, as shown in FIG. 2, it is possible to have a chain conductive fine particle group having a “neck”.
(4) Further, when the chain conductive fine particle group is a metal oxide, it can be prepared as follows.
[0036]
First, an alcohol solution containing a metal salt or metal alkoxide at a concentration of 0.1 to 5% by weight is heated and hydrolyzed. At this time, it may be added to warm water or an alkali as necessary. By such hydrolysis, a gel dispersion of a metal hydroxide having a primary particle diameter of 1 to 100 nm is prepared. Next, the gel dispersion is filtered and washed, and fired in air at a temperature of 200 to 800 ° C. to prepare conductive metal oxide fine particles.
[0037]
Subsequently, this powder is dispersed in acidic or alkaline water and / or alcohol solvent to obtain a dispersion having a concentration of 10 to 50% by weight. If necessary, this dispersion is mechanically treated in the presence of an organic stabilizer as described above. Distributed processing. If necessary, an autoclave treatment may be performed as described above.
[0038]
(5) Furthermore, the chain conductive fine particle group composed of the metal oxide, after filtering and washing the gel dispersion, after the metal hydroxide in the presence of an organic stabilizer as necessary. It can be obtained by autoclaving and further mechanical dispersion treatment. In this case, the ionic impurities may be removed by an ion exchange resin treatment as described above.
[0039]
The chain-like conductive fine particle group thus obtained is usually taken out from the resulting dispersion by a method such as centrifugation, washed with an acid as necessary, and then dispersed in a polar solvent described below. Is done. Moreover, the obtained dispersion liquid containing the chain | strand-shaped electroconductive fine particle group can also be used as a coating liquid as it is.
[0040]
Preparation of coating solution for forming transparent conductive film
In the first coating liquid for forming a transparent conductive film according to the present invention, such a chain conductive fine particle group is dispersed in a polar solvent. Examples of polar solvents used in the present invention include water; alcohols such as methanol, ethanol, propanol, butanol, diacetone alcohol, furfuryl alcohol, tetrahydrofurfuryl alcohol, ethylene glycol, hexylene glycol; acetic acid methyl ester, ethyl acetate Esters such as esters; ethers such as diethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether and diethylene glycol monoethyl ether; ketones such as acetone, methyl ethyl ketone, acetylacetone and acetoacetate And the like. These may be used singly or in combination of two or more.
[0041]
Moreover, the coating liquid for forming a transparent conductive film according to the present invention may further contain a matrix forming component. The matrix-forming component acts as a binder for conductive fine particles when coating with the coating liquid for forming a transparent conductive film according to the present invention. Such matrix forming components include SiO2Precursor, TiO2Precursor, ZrO2At least one selected from precursors or organic polymers is preferably used, and among them, particularly SiO.2Precursors and organic polymers are preferred. SiO2Specific examples of the precursor include a polycondensate obtained by hydrolyzing an organosilicon compound such as alkoxysilane or a silicate polycondensate obtained by dealkalizing an aqueous alkali metal silicate solution. Examples of the organic polymer include paint resins such as polyethylene, polyphenol, epoxy, polyamino acid, and polystyrene.
[0042]
In the coating liquid for forming a transparent conductive film according to the present invention, the conductive fine particles are desirably contained at a concentration of 0.05 to 5% by weight, preferably 0.1 to 2% by weight.
[0043]
The matrix-forming component may be contained in an amount of 0.01 to 0.9 parts by weight, preferably 0.1 to 0.5 parts by weight, per 1 part by weight of the chain conductive fine particles.
[0044]
In addition, the coating liquid for forming a transparent conductive film according to the present invention may contain an organic stabilizer in order to improve the dispersibility of the conductive fine particles. Specific examples of such organic stabilizers include gelatin, polyvinyl alcohol, polyvinyl pyrrolidone, polyacrylic acid, ethylenediaminetetraacetic acid, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, sebacic acid, maleic acid, Examples thereof include polyvalent carboxylic acids such as fumaric acid, phthalic acid and citric acid and salts thereof, cellulose derivatives, heterocyclic compounds, surfactants, and mixtures thereof.
[0045]
Such an organic stabilizer may be contained in an amount of 0.005 to 0.5 parts by weight, preferably 0.01 to 0.5 parts by weight, with respect to 1 part by weight of the conductive fine particles. When the amount of the organic stabilizer is less than 0.005 parts by weight, sufficient dispersibility cannot be obtained, and when it exceeds 0.5 parts by weight, the conductivity may be inhibited.
[0046]
Furthermore, the coating liquid for forming a transparent conductive film according to the present invention contains a dye, a coloring pigment or colored particles so that the visible light transmittance is constant in a wide wavelength range of visible light of the coating liquid. Also good.
[0047]
Known dyes, colored pigments or colored particles can be used, and specific examples thereof include fine-particle carbon, diazo dyes, titanium black, phthalocyanine pigments, and dioxazine pigments.
[0048]
When the coating liquid for forming a transparent conductive film contains a dye, a colored pigment or colored particles, the solid content concentration in the coating liquid for forming a transparent conductive film (total amount of conductive fine particles and additives such as dye and pigment) Is preferably 15% by weight or less, and preferably in the range of 0.15 to 5% by weight, from the viewpoint of the fluidity of the coating liquid and the dispersibility of particulate components such as conductive fine particles in the coating liquid.
[0049]
Furthermore, the coating liquid for forming a transparent conductive film according to the present invention includes alkali metal ions, ammonium ions and polyvalent metal ions present in the liquid, inorganic anions such as mineral acids, organic anions such as acetic acid and formic acid, etc. The total amount of ion concentration is desirably 1000 ppm or less. In particular, inorganic anions such as mineral acids may inhibit the stability and dispersibility of the chain conductive fine particle group, and it is desirable that the content in the coating solution is smaller. When the ion concentration is lowered, the dispersed state of the particulate component contained in the coating liquid for forming the transparent conductive film, particularly the conductive fine particles, is improved, and almost all the aggregated particles other than the chain conductive fine particle group are mostly collected. A coating solution not containing is obtained. Such a monodispersed state of the chain conductive fine particles in the coating liquid for forming a transparent conductive film is maintained even in the process of forming the transparent conductive film. For this reason, when a transparent conductive film is formed from a coating liquid for forming a transparent conductive film having a low ion concentration, only the chain conductive fine particle group is observed in the transparent conductive film.
[0050]
In addition, when a coating liquid for forming a transparent conductive film having a low ion concentration as described above is used, the group of chain conductive fine particles can be well dispersed and uniformly arranged in the transparent conductive film. Compared to the case where the conductive fine particles are aggregated in the conductive film, it is possible to provide a transparent conductive film having the same conductivity with fewer conductive fine particles. Further, it is possible to form a transparent conductive film free from point defects and thickness irregularities that are thought to be caused by aggregation of the chain conductive fine particle groups on the substrate.
[0051]
The method of deionization treatment for obtaining such a coating solution for forming a transparent conductive film having a low ion concentration is a method in which the ion concentration contained in the coating solution finally falls within the above range. If it is not particularly limited, for example, a dispersion prepared from a group of chain conductive fine particles, or a coating solution prepared from the dispersion is used as a cation exchange resin and / or an anion exchange resin or an amphoteric ion exchange resin. The method of making it contact, The method of wash | cleaning these liquids using an ultrafiltration membrane, etc. are mentioned.
[0083]
[Base material with transparent conductive film]
Next, the substrate with a transparent conductive film according to the present invention will be specifically described.
The substrate with a transparent conductive film according to the present invention is
It consists of a base material, a transparent conductive film provided on the base material, and a transparent film provided on the transparent conductive film.
[0084]
In the present invention, a known substrate can be used, and specific examples include films, sheets, and other molded bodies made of glass, plastics, ceramics, and the like.
[0085]
  Transparent conductive coating
  The transparent conductive film is used in the present invention.TransparentIt is formed by applying and drying a conductive film forming coating solution on a substrate.
[0086]
As a method for forming a transparent conductive film, for example, a coating liquid for forming a transparent conductive film is applied on a substrate by a dipping method, a spinner method, a spray method, a roll coater method, a flexographic printing method, or the like. Dry at a temperature ranging from room temperature to about 90 ° C.
[0087]
When the matrix-forming component as described above is contained in the coating liquid for forming a transparent conductive film, the matrix-forming component may be cured.
Examples of the curing process include the following methods.
[0088]
(1) Heat curing
The coating film after drying is heated to cure the matrix component. The heat treatment temperature at this time is 100 ° C. or higher, preferably 150 to 300 ° C. If it is less than 100 degreeC, a matrix formation component may not fully harden | cure. Moreover, although the upper limit of heat processing temperature changes with kinds of base material, it should just be below the transition point of a base material.
[0089]
(2) Electromagnetic curing
The matrix component is cured by irradiating the coating film with an electromagnetic wave having a wavelength shorter than that of visible light after the coating process or the drying process or during the drying process. As the electromagnetic wave to be irradiated to promote the curing of the matrix forming component, ultraviolet rays, electron beams, X-rays, γ rays, etc. are used depending on the type of the matrix forming component. For example, in order to accelerate the curing of the ultraviolet curable matrix forming component, for example, the emission intensity becomes maximum at about 250 nm and 360 nm, and the light intensity becomes 10 mW / m.2Using the above high-pressure mercury lamp as the UV source, 100 mJ / cm2The ultraviolet ray having the above energy amount is irradiated.
[0090]
(3) Gas curing
The matrix-forming component is cured by exposing the coating to a gas atmosphere that promotes the curing reaction of the matrix-forming component after or during the coating or drying step. Among the matrix forming components, there is a matrix forming component whose curing is accelerated by an active gas such as ammonia. A transparent conductive film containing such a matrix forming component is used at a gas concentration of 100 to 100,000 ppm, preferably 1000 to 10,000 ppm. Curing of the matrix-forming component can be greatly accelerated by treating for 1 to 60 minutes under a certain curing-promoting gas atmosphere.
[0091]
The film thickness of the transparent conductive film formed by the method as described above is preferably in the range of about 50 to 200 nm, and preferably in the range of 10 to 150 nm. A coated substrate can be obtained.
Transparent coating
In the substrate with a transparent conductive film according to the present invention, a transparent film having a refractive index lower than that of the transparent conductive film is formed on such a transparent conductive film.
[0092]
The film thickness of the formed transparent film is 50 to 300 nm, preferably 80 to 200 nm.
Such a transparent film is formed from, for example, inorganic oxides such as silica, titania and zirconia, and composite oxides thereof. In the present invention, a silica-based film made of a hydrolyzable polycondensate of a hydrolyzable organosilicon compound or a silicate polycondensate obtained by dealkalizing an alkali metal silicate aqueous solution is particularly preferable as the transparent film. The base material with a transparent conductive film on which such a transparent film is formed is excellent in antireflection performance.
[0093]
The transparent film may contain additives such as fine particles made of a low refractive index material such as magnesium fluoride, if necessary.
In the present invention, a transparent film having a refractive index lower than that of the fine particle layer is formed on the transparent conductive film formed as described above.
[0094]
The film thickness of the transparent coating is preferably in the range of 50 to 300 nm, and preferably in the range of 80 to 200 nm. When the film thickness is in such a range, excellent antireflection properties are exhibited. The method for forming the transparent film is not particularly limited, and depending on the material of the transparent film, a dry thin film forming method such as a vacuum evaporation method, a sputtering method, or an ion plating method, or the dipping method or spinner method as described above. A wet thin film forming method such as a spray method, a roll coater method, or a flexographic printing method can be employed.
[0095]
When the transparent film is formed by a wet thin film forming method, a conventionally known transparent film forming coating solution, for example, an inorganic oxide precursor such as silica, titania, zirconia, or a composite oxide precursor thereof is used as a transparent film forming component. It is possible to use a coating liquid for forming a transparent film contained as
[0096]
In the present invention, as a coating liquid for forming a transparent film, a hydrolytic polycondensate of a hydrolyzable organosilicon compound or a silica-based transparent film forming coating containing silicic acid obtained by dealkalizing an alkali metal silicate aqueous solution In particular, a coating liquid for forming a silica-based transparent film containing a hydrolyzed polycondensate of alkoxysilane represented by the following general formula [1] is preferable. A silica-based film formed from such a coating solution has a refractive index smaller than that of the transparent conductive film, and the obtained substrate with a transparent film is excellent in antireflection properties.
[0097]
RaSi (OR ')4-a            [1]
(In the formula, R is a vinyl group, an aryl group, an acrylic group, an alkyl group having 1 to 8 carbon atoms, a hydrogen atom or a halogen atom, and R ′ is a vinyl group, an aryl group, an acrylic group, or an alkyl group having 1 to 8 carbon atoms. An alkyl group, -C2HFourOCnH2n + 1(N = 1 to 4) or a hydrogen atom, and a is an integer of 1 to 3. )
Such alkoxysilanes include tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane, tetrabutoxysilane, tetraoctylsilane, methyltrimethoxysilane, methyltriethoxysilane, ethyltriethoxysilane, methyltriisopropoxysilane, Examples include vinyltrimethoxysilane, phenyltrimethoxysilane, and dimethyldimethoxysilane.
[0098]
When one or more of the above alkoxysilanes are hydrolyzed in the presence of an acid catalyst in, for example, a water-alcohol mixed solvent, a coating solution for forming a transparent film containing a hydrolysis polycondensate of alkoxysilane is obtained. . It is preferable that the density | concentration of the film formation component contained in such a coating liquid is 0.5 to 20 weight% in conversion of an oxide.
[0099]
The coating liquid for forming a transparent coating used in the present invention is subjected to deionization treatment in the same manner as the coating liquid for forming a transparent conductive film according to the present invention, and the ion concentration of the transparent conductive coating liquid is You may reduce to the same level as the density | concentration in the coating liquid for transparent conductive film formation.
[0100]
Furthermore, the coating liquid for forming a transparent film used in the present invention contains fine particles composed of a low refractive index material such as magnesium fluoride, and a small amount of conductivity that does not impair the transparency and antireflection performance of the transparent film. Additives such as fine particles, dyes, coloring pigments, and fine particle carbon may be contained.
[0101]
In the present invention, a film formed by applying such a coating solution for forming a transparent film is dried at a temperature of 150 ° C. or higher, heated at 150 ° C. or higher after drying, or an uncured film from visible light. Alternatively, a treatment such as irradiation with an electromagnetic wave such as ultraviolet rays having a short wavelength, electron beam, X-ray, or γ-ray, or exposure to an active gas atmosphere such as ammonia may be performed. When the treatment is performed in this manner, curing of the film-forming component is promoted, and the hardness of the obtained transparent film can be increased. Moreover, when performing the said hardening process, when apply | coating the coating liquid for transparent film formation, it is preferable to apply | coat the coating liquid for transparent film formation, hold | maintaining a transparent conductive film at about 40-90 degreeC. While holding the transparent conductive film at about 40 to 90 ° C., by applying a coating solution for forming a transparent film on the transparent conductive film, ring-shaped irregularities are formed on the surface of the transparent film, and the glare A substrate with a transparent coating with a small amount of antiglare can be obtained.
[0102]
[Display device]
The substrate with a transparent conductive film according to the present invention has a surface resistance in the range of 102 to 104 Ω / □ necessary for electromagnetic shielding, and has sufficient antireflection performance and antiglare properties in the visible light region and the near infrared region. The transparent conductive film-coated substrate having the property is suitably used as a front plate of a display device.
[0103]
The display device according to the present invention is a device that electrically displays an image such as a cathode ray tube (CRT), a fluorescent display tube (FIP), a plasma display (PDP), a liquid crystal display (LCD), and the like. A front plate made of a substrate with a transparent conductive film.
[0104]
When a conventional display device having a front plate is operated, an image is displayed on the front plate and electromagnetic waves are emitted from the front plate at the same time. This electromagnetic wave affects the human body of the observer. In the device, the front plate is 102-10FourSince it is composed of a substrate with a transparent conductive film having a surface resistance of Ω / □, it is possible to effectively shield such an electromagnetic wave and an electromagnetic field generated with the emission of the electromagnetic wave.
[0105]
In addition, when reflected light is generated on the front plate of the display device, the display image is difficult to see due to the reflected light. In the display device according to the present invention, the front plate has sufficient antireflection performance in the visible light region and the near infrared region. And since it is comprised with the base material with a transparent conductive film which has anti-glare property, such reflected light can be prevented effectively.
[0106]
Furthermore, the front plate of the cathode ray tube is composed of a substrate with a transparent conductive film according to the present invention, and a small amount of at least one of the transparent conductive film and the transparent film formed thereon is included in the transparent conductive film. When dyes or pigments are contained, these dyes or pigments each absorb light having a specific wavelength, thereby improving the contrast of a display image broadcast from the cathode ray tube.
[0107]
【The invention's effect】
According to the present invention, the conductivity and electromagnetic shielding properties are excellent, the light transmittance can be controlled, the antireflection performance and the antiglare property, and the transparent conductive film that is highly reliable can be formed. A coating liquid for forming a conductive film can be obtained.
[0108]
Further, according to the present invention, a transparent conductive film having excellent electrical conductivity and electromagnetic shielding properties, light transmittance control, antireflection performance and antiglare property, and high reliability is formed. A substrate with a transparent conductive film can be obtained.
[0109]
If such a substrate with a transparent conductive film is used as a front plate of a display device, a display device having excellent electromagnetic shielding properties and antireflection properties and antiglare properties can be obtained.
[0110]
【Example】
EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to these Examples.
[0111]
[Production Examples]
a) Preparation of conductive fine particle dispersion
Table 1 shows the composition of the conductive fine particle dispersion used in this example and the comparative example.
[0112]
Chain of conductive fine particles (P-1)
First, an aqueous solution was prepared by adding silver nitrate and an aqueous palladium nitrate solution to 100 g of pure water in advance so that the concentration was 10% by weight in terms of metal and the metal species of the composite metal was in the weight ratio shown in Table 1. In this aqueous solution, an aqueous solution containing trisodium citrate (an organic stabilizer and a reducing agent) in an amount of 0.01 part by weight per part by weight of the composite metal, the total number of moles of silver nitrate and palladium nitrate, etc. A mixed solution in which a molar number of ferrous sulfate (reducing agent) aqueous solution was mixed was added, and stirred for 1 hour in a nitrogen atmosphere to obtain a dispersion of composite metal fine particles.
[0113]
The obtained dispersion is separated by a centrifuge and then acid-washed with HCl having a concentration of 1% by weight, and polyacrylic acid is added so as to be 0.0128 parts by weight per 1 part by weight of the composite metal and dispersed in pure water. Thus, a dispersion having a concentration shown in Table 1 was prepared. Subsequently, the obtained dispersion was treated with a nanomizer system (Nanomizer Co., Ltd .: LA-33-S) to obtain a dispersion of chain conductive fine particles (P-1).
[0114]
Chain of conductive fine particles (P-2)
After adding chloroplatinic acid to 100 g of pure water in advance, adding an acetone solution of palladium acetate so that the concentration in terms of metal is 10% by weight and the metal species of the composite metal is in the weight ratio of Table 1, Trisodium citrate having a total number of moles of chloroplatinic acid and palladium acetate and an equimolar number of trisodium citrate was added and stirred for 1 hour under a nitrogen atmosphere to obtain a composite metal fine particle dispersion.
[0115]
The obtained dispersion is separated by a centrifuge and then acid-washed with HCl having a concentration of 1% by weight, and polyacrylic acid is added so as to be 0.0128 parts by weight per 1 part by weight of the composite metal and dispersed in pure water. Thus, a dispersion having a concentration shown in Table 1 was prepared. Subsequently, the obtained dispersion was subjected to a nanomizer system treatment to obtain a dispersion of chain conductive fine particles (P-2).
[0116]
Chain of conductive fine particles (P-3)
The prepared dispersion of conductive fine particles (P-1) was placed in an autoclave under a nitrogen atmosphere at 150 ° C. and 10.0 kg / cm.2The mixture was stirred for 1 hour and then treated using the nanomizer system to obtain a dispersion of chain conductive fine particles (P-3).
[0117]
Chain of conductive fine particles (P-4)
To the prepared dispersion of conductive fine particles (P-1), an aqueous silver nitrate solution is added so that the metal species of the composite metal is in the weight ratio shown in Table 1, and an aqueous ferrous sulfate solution having an equimolar number of silver nitrate is added. The mixture was stirred for 1 hour in a nitrogen atmosphere to obtain a dispersion of composite metal fine particles. The obtained dispersion was separated by a centrifuge, washed with water and dispersed in pure water to prepare dispersions having the concentrations shown in Table 1. Subsequently, the obtained dispersion was processed with a nanomizer system to obtain a dispersion of chain conductive fine particles (P-4).
[0118]
Rod-shaped conductive fine particles (P-5)
To 100 g of pure water, fibrous alumina fine particles having an average length of 50 nm and an average cross-sectional diameter of 10 nm are added in advance so as to have a weight ratio shown in Table 1 as a chain inorganic oxide. An aqueous solution to which silver nitrate and an aqueous palladium nitrate solution were added so as to have a weight ratio shown in Table 1 was prepared. In this aqueous solution, an aqueous solution containing trisodium citrate (an organic stabilizer and a reducing agent) in an amount of 0.01 part by weight per 1 part by weight of the composite metal, the concentration in terms of metal is 10% by weight, A mixed solution in which a total number of moles of silver nitrate and palladium nitrate was mixed with an equimolar number of ferrous sulfate (reducing agent) aqueous solution was added and stirred for 1 hour in a nitrogen atmosphere to obtain a dispersion of composite metal fine particles.
[0119]
The obtained dispersion is separated by a centrifuge and then acid-washed with HCl having a concentration of 1% by weight, and polyacrylic acid is added so as to be 0.0128 parts by weight per 1 part by weight of the composite metal and dispersed in pure water. Thus, a dispersion having a concentration shown in Table 1 was prepared. Subsequently, the obtained dispersion was treated with a nanomizer system (Nanomizer Co., Ltd .: LA-33-S) to obtain a dispersion of rod-shaped conductive fine particle groups (P-5).
[0120]
Rod-shaped conductive fine particles (P-6)
The dispersion of composite alumina fine particles (P-1) is mixed with the dispersion of fibrous alumina fine particles used in the conductive fine particles (P-5) so that the weight ratio shown in Table 1 is satisfied, and a nanomizer system is used. Thus, a dispersion of rod-shaped composite metal fine particles (P-6) was obtained.
[0122]
Monodisperse conductive fine particles (P-8)
An aqueous solution in which silver nitrate and an aqueous palladium nitrate solution were added to 100 g of pure water in advance so that the concentration in terms of metal was 10% by weight and the metal species of the composite metal was in the weight ratio shown in Table 1 was prepared. In this aqueous solution, an aqueous solution containing trisodium citrate (an organic stabilizer and a reducing agent) in an amount of 0.01 part by weight per part by weight of the composite metal, the total number of moles of silver nitrate and palladium nitrate, etc. A mixed solution in which a molar number of ferrous sulfate (reducing agent) aqueous solution was mixed was added, and stirred for 1 hour in a nitrogen atmosphere to obtain a dispersion of composite metal fine particles.
[0123]
The obtained dispersion was separated by a centrifugal separator, washed with water and dispersed in pure water to prepare monodisperse conductive fine particles (P-8) having the concentrations shown in Table 1.
Conductive fine particles (P-9)
An aqueous solution in which silver nitrate and an aqueous palladium nitrate solution were added to 100 g of pure water in advance so that the concentration in terms of metal was 10% by weight and the metal species of the composite metal was in the weight ratio shown in Table 1 was prepared. This aqueous solution contains an aqueous solution containing trisodium citrate (an organic stabilizer and a reducing agent) in an amount of 0.01 part by weight per part by weight of the composite metal, and the total number of moles of silver nitrate and palladium nitrate. A mixed solution in which a 3-fold mole number of ferrous sulfate (reducing agent) aqueous solution was mixed was added and stirred for 1 hour in a nitrogen atmosphere to obtain a dispersion of composite metal fine particles. The obtained dispersion is separated by a centrifuge and then acid-washed with HCl having a concentration of 1% by weight, and polyacrylic acid is added so as to be 0.0128 parts by weight per 1 part by weight of the composite metal and dispersed in pure water. Thus, a dispersion having a concentration shown in Table 1 was prepared. Next, the obtained dispersion was pulverized with a nanomizer to obtain a dispersion of composite metal fine particles (P-9). The shape of the obtained composite metal fine particles (P-9) was a chain of conductive fine particles.
[0124]
Conductive fine particles (P-10)
An aqueous solution in which silver nitrate and an aqueous palladium nitrate solution were added to 100 g of pure water in advance so that the concentration in terms of metal was 10% by weight and the metal species of the composite metal was in the weight ratio shown in Table 1 was prepared. This aqueous solution contains an aqueous solution containing trisodium citrate (an organic stabilizer and a reducing agent) in an amount of 0.01 part by weight per part by weight of the composite metal, and the total number of moles of silver nitrate and palladium nitrate. A mixed solution prepared by mixing 3 times mole number of ferrous sulfate (reducing agent) aqueous solution was added and stirred for 1 hour in a nitrogen atmosphere to obtain a dispersion of composite metal fine particles. The obtained dispersion is separated by a centrifuge and then acid-washed with HCl having a concentration of 1% by weight. Polyacrylic acid is added to 0.03 part by weight per part by weight of the composite metal, and purified water is added. Dispersions having the concentrations shown in Table 1 were prepared by dispersing. Next, the obtained dispersion was pulverized with a nanomizer to obtain a dispersion of composite metal fine particles (P-10). The shape of the obtained composite metal fine particles (P-10) was a chain conductive fine particle group.
[0125]
Conductive fine particles ( P-11 )
An aqueous solution in which silver nitrate and an aqueous palladium nitrate solution were added to 100 g of pure water in advance so that the concentration in terms of metal was 10% by weight and the metal species of the composite metal was in the weight ratio shown in Table 1 was prepared. This aqueous solution contains an aqueous solution containing trisodium citrate (an organic stabilizer and a reducing agent) in an amount of 0.01 part by weight per part by weight of the composite metal, and the total number of moles of silver nitrate and palladium nitrate. A mixed solution in which a 3-fold mole number of ferrous sulfate (reducing agent) aqueous solution was mixed was added and stirred for 1 hour in a nitrogen atmosphere to obtain a dispersion of composite metal fine particles. The obtained dispersion is separated by a centrifuge and then acid-washed with HCl having a concentration of 1% by weight, and polyacrylic acid is added to 0.20 part by weight per part by weight of the composite metal. Dispersions having the concentrations shown in Table 1 were prepared by dispersing. Next, the obtained dispersion was pulverized with a nanomizer to obtain a dispersion of composite metal fine particles (P-11). The obtained composite metal fine particles (P-11) were agglomerated particles.
[0126]
Conductive oxide fine particles ( P-12 )
To 100 g of pure water, indium nitrate and tin fluoride are added in advance so that the metal conversion becomes 10% by weight and the metal species of the composite metal is in the weight ratio shown in Table 1, and 10% by weight of potassium hydroxide is added thereto. A composite metal particle precipitate was prepared. After the precipitate of the composite metal particles is washed with water, pure water is added so as to be 10% by weight in terms of metal, pure water and acetylacetone (organic dispersant) are added thereto, and the mixture is treated with a sand mill and a nanomizer system. A dispersion of monodispersed composite metal fine particles (P-12) was obtained.
[0127]
Conductive carbon fine particles (P-13)
Conductive fine particle (P-13) dispersion liquid was prepared by adding conductive carbon fine particles (manufactured by Mitsubishi Chemical Corporation: MA-100) as a colorant to 100 g of pure water so as to have the concentration shown in Table 1.
[0128]
In addition, the primary particle of the conductive fine particles of the present invention, the observation of the chain shape and the rod shape, the measurement of the particle diameter, the particle length, and the like were measured using a scanning electron microscope (JEOL Ltd .: JMS5300). Was observed.
[0129]
The aspect ratio was expressed as L / D, where L is the particle length, and D is the cross-sectional diameter of the particle. The aspect ratio of the chain conductive fine particle group was such that the particle length was L and the primary particle diameter was the cross-sectional diameter D of the particles.
[0130]
[Table 1]
Figure 0004522505
[0131]
b) Matrix-forming component liquid ( M ) Preparation of
Normal ethyl silicate (SiO2: 28 wt%) 50 g of ethanol, 194.6 g of ethanol, 1.4 g of concentrated nitric acid and 34 g of pure water were stirred at room temperature for 5 hours, and SiO 22A liquid (M) containing a matrix-forming component having a concentration of 5% by weight was prepared.
[0132]
c) Preparation of coating solution for forming transparent conductive film
(P-1) to (P-13) dispersions shown in Table 1 and (A) solution containing the above-mentioned matrix-forming components, water, t-butanol, butyl cellosolve, citric acid and N-methyl-2- Using pyrrolidone, coating liquids (C-1) to (C-14) for forming transparent conductive films shown in Table 2 were prepared.
[0133]
[Table 2]
Figure 0004522505
[0134]
d) Coating liquid for forming transparent film (B-1) Preparation of
A mixed solvent of ethanol / butanol / diacetone alcohol / isopropanol (2: 1: 1: 5 weight ratio) is added to the solution (A) containing the matrix-forming component, and SiO 2 is added.2A coating solution (B-1) for forming a transparent film having a concentration of 1% by weight was prepared.
[0135]
In addition, the coating liquid for forming a conductive film and the coating liquid for forming a transparent film used in the present invention are deionized with an amphoteric ion exchange resin (Diaion SMNUPB, manufactured by Mitsubishi Chemical Corporation). The ion concentration was adjusted.
[0136]
In addition, the alkali metal ion concentration and alkaline earth metal ion concentration in the coating solution are measured by atomic absorption, the other metal ion concentrations are measured by emission spectroscopy, and the ion concentrations of ammonium ions and anions are measured by ion chromatography. Measured by the method.
[0137]
Examples 1-9
Manufacture of panel glass with transparent conductive coating
While maintaining the surface of the CRT panel glass (14 ") at 40 ° C., the above-mentioned coating liquids (C-1) to (C-9) for forming the transparent conductive film were respectively applied with a spinner method at 100 rpm for 90 seconds. It was applied and dried.
[0138]
Next, on the transparent conductive film thus formed, the coating liquid for forming a transparent film (B-1) was similarly applied and dried under the conditions of 100 rpm and 90 seconds by the spinner method. Firing was performed under the conditions shown to obtain a substrate with a transparent conductive film.
[0139]
The surface resistance of these substrates with transparent conductive films was measured with a surface resistance meter (Mitsubishi Yuka Co., Ltd .: LORESTA), and haze was measured with a haze computer (Nippon Denshoku Co., Ltd .: 3000A). . The reflectivity was measured using a reflectometer (manufactured by Otsuka Electronics Co., Ltd .: MCPD-2000), and the reflectivity was the reflectivity at the lowest reflectivity in the wavelength range of 400 to 700 nm.
[0140]
The results are shown in Table 3.
[0141]
[Comparative Examples 1-5]
Manufacture of panel glass with transparent conductive coating
While maintaining the surface of the CRT panel glass (14 ″) at 40 ° C., the above-mentioned coating liquids for transparent conductive film formation (C-10) to (C-14) are respectively applied at 100 rpm for 90 seconds by the spinner method. It was applied and dried.
[0142]
Next, on the transparent conductive film thus formed, the coating liquid for forming a transparent film (B-1) was similarly applied and dried under the conditions of 100 rpm and 90 seconds by the spinner method. Firing was performed under the conditions shown to obtain a substrate with a transparent conductive film.
[0143]
The surface resistance of these substrates with transparent conductive films was measured with a surface resistance meter (Mitsubishi Yuka Co., Ltd .: LORESTA), and haze was measured with a haze computer (Nippon Denshoku Co., Ltd .: 3000A). . The reflectivity was measured using a reflectometer (manufactured by Otsuka Electronics Co., Ltd .: MCPD-2000), and the reflectivity was the reflectivity at the lowest reflectivity in the wavelength range of 400 to 700 nm.
[0144]
The results are shown in Table 3.
[0145]
[Table 3]
Figure 0004522505

[Brief description of the drawings]
FIG. 1 is a schematic view showing one embodiment of a group of chain conductive fine particles contained in a coating liquid for forming a transparent conductive film according to the present invention.
FIG. 2 is a schematic view showing another embodiment of a group of chain conductive fine particles contained in a coating liquid for forming a transparent conductive film according to the present invention.
FIG. 3 is a schematic view showing another embodiment of a group of chain conductive fine particles contained in a coating liquid for forming a transparent conductive film according to the present invention.
FIG. 4 is a schematic view showing one embodiment of rod-like conductive fine particles contained in a coating liquid for forming a transparent conductive film according to the present invention.
FIG. 5 is a schematic view showing another embodiment of rod-like conductive fine particles contained in a coating liquid for forming a transparent conductive film according to the present invention.
FIG. 6 is a schematic view showing one embodiment of a group of rod-like conductive fine particles contained in a coating liquid for forming a transparent conductive film according to the present invention.

Claims (10)

導電性微粒子と極性溶媒とを含む透明導電性被膜形成用塗布液において、導電性微粒子が、平均粒子径が1〜100nmの範囲にある一次粒子が2個以上鎖状に連続して接合した鎖状構造を有する鎖状導電性微粒子群からなり、かつ、該鎖状導電性微粒子群が、金属微粒子分散スラリーまたは金属水酸化物ゲルスラリーを、有機系安定剤存在下に、メカニカル分散処理を行い得られたものであることを特徴とする透明導電性被膜形成用塗布液。In a coating liquid for forming a transparent conductive film containing conductive fine particles and a polar solvent, conductive fine particles are chains in which two or more primary particles having an average particle diameter in the range of 1 to 100 nm are continuously joined in a chain shape. Ri do from conductive fine chain particles having Jo structure, and the chain-like conductive fine group, a metal fine particle dispersed slurry or metal hydroxide gel slurry, in the presence of an organic-based stabilizer, perform a mechanical dispersion process A coating liquid for forming a transparent conductive film, which is obtained . 前記鎖状導電性微粒子群の長さが2〜200nmの範囲にあることを特徴とする請求項1に記載の透明導電性被膜形成用塗布液。  2. The coating liquid for forming a transparent conductive film according to claim 1, wherein the length of the chain conductive fine particle group is in the range of 2 to 200 nm. 前記鎖状導電性微粒子群がAu,Ag,Pd,Cu,Ni,Ru,Rh,Sn,In,Sb,Fe,Pt,Ti,Cr,Co,Al,Zn,Ta,Pb,Os,Irから選ばれる一種以上の元素からなる金属、水酸化物、酸化物、あるいは金属ドープ酸化物からなることを特徴とする請求項1または2に記載の透明導電性被膜形成用塗布液。  The chain-like conductive fine particle group is composed of Au, Ag, Pd, Cu, Ni, Ru, Rh, Sn, In, Sb, Fe, Pt, Ti, Cr, Co, Al, Zn, Ta, Pb, Os, Ir. The coating liquid for forming a transparent conductive film according to claim 1, comprising a metal, a hydroxide, an oxide, or a metal-doped oxide composed of one or more selected elements. 前記鎖状導電性微粒子群が、金属微粒子分散スラリーまたは金属水酸化物ゲルスラリーに、加圧下で加熱処理を行ったのち、メカニカル分散処理を行い得られたものであることを特徴とする請求項1〜3のいずれかに記載の透明導電性被膜形成用塗布液。  The chain conductive fine particle group is obtained by subjecting a metal fine particle dispersed slurry or a metal hydroxide gel slurry to a heat treatment under pressure, followed by a mechanical dispersion treatment. The coating liquid for transparent conductive film formation in any one of -3. さらに有機系安定剤を含むことを特徴とする請求項1〜4のいずれかに記載の透明導電性被膜形成用塗布液。  The coating liquid for forming a transparent conductive film according to any one of claims 1 to 4, further comprising an organic stabilizer. さらにマトリックス形成成分を含むことを特徴とする請求項1〜5のいずれかに記載の透明導電性被膜形成用塗布液。  Furthermore, a matrix formation component is included, The coating liquid for transparent conductive film formation in any one of Claims 1-5 characterized by the above-mentioned. 前記マトリックス形成成分がSiO2前駆体、TiO2前駆体、ZrO2前駆体または有機高分子から選ばれる少なくとも一種からなることを特徴とする請求項6に記載の透明導電性被膜形成用塗布液。The coating liquid for forming a transparent conductive film according to claim 6, wherein the matrix forming component comprises at least one selected from a SiO 2 precursor, a TiO 2 precursor, a ZrO 2 precursor, or an organic polymer. さらに、染料、着色顔料または着色粒子を含むことを特徴とする請求項1〜7のいずれかに記載の透明導電性被膜形成用塗布液。  Furthermore, the coating liquid for transparent conductive film formation in any one of Claims 1-7 containing dye, a coloring pigment, or a colored particle. 基材と、請求項1〜8のいずれかに記載の透明導電性被膜形成用塗布液を基材上に塗布してなる透明導電性被膜と、該透明導電性被膜上に設けられ、かつ該透明導電性被膜よりも屈折率が低い透明被膜とからなることを特徴とする透明導電性被膜付基材。  A substrate, a transparent conductive film formed by applying the transparent conductive film-forming coating solution according to any one of claims 1 to 8 on the substrate, the transparent conductive film, and the transparent conductive film A substrate with a transparent conductive film, comprising: a transparent film having a refractive index lower than that of the transparent conductive film. 請求項9に記載の透明導電性被膜付基材から構成される前面板を備え、透明被膜が該前面板の外表面に形成されていることを特徴とする表示装置。  A display device comprising a front plate comprising the substrate with a transparent conductive coating according to claim 9, wherein the transparent coating is formed on an outer surface of the front plate.
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JP2009084640A (en) * 2007-09-28 2009-04-23 Achilles Corp Wire-shaped metal particulate-containing composition and conductive translucent film
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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH08167320A (en) * 1994-12-13 1996-06-25 Pentel Kk Conductive composition
JPH08302246A (en) * 1995-05-09 1996-11-19 Sumitomo Osaka Cement Co Ltd Coating for forming transparent membrane having high electroconductivity and high membrane strength, formation of transparent membrane having high electroconductivity and membrane, strength, and cathode ray tube
JPH10188681A (en) * 1996-09-26 1998-07-21 Catalysts & Chem Ind Co Ltd Transparent-conductive-film forming application liquid, base material with transparent conductive film, its manufacture, and display device
JP2000124662A (en) * 1998-10-14 2000-04-28 Sumitomo Osaka Cement Co Ltd Transparent conductive film and display device

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3399270B2 (en) * 1996-12-25 2003-04-21 三菱マテリアル株式会社 Transparent conductive film and composition for forming the same

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH08167320A (en) * 1994-12-13 1996-06-25 Pentel Kk Conductive composition
JPH08302246A (en) * 1995-05-09 1996-11-19 Sumitomo Osaka Cement Co Ltd Coating for forming transparent membrane having high electroconductivity and high membrane strength, formation of transparent membrane having high electroconductivity and membrane, strength, and cathode ray tube
JPH10188681A (en) * 1996-09-26 1998-07-21 Catalysts & Chem Ind Co Ltd Transparent-conductive-film forming application liquid, base material with transparent conductive film, its manufacture, and display device
JP2000124662A (en) * 1998-10-14 2000-04-28 Sumitomo Osaka Cement Co Ltd Transparent conductive film and display device

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