JP3913962B2 - Liquid crystal display cell and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid crystal display cell having a substrate with a transparent electrode on which a transparent electrode protective film is formed, the protective film being excellent in the adhesion property with the electrode film and alignment film, rapidly removing electrostatic charges generating in the alignment film when the alignment film is subjected to a rubbing treatment, preventing electrification of the alignment film and causing no dielectric breakdown. SOLUTION: In the liquid crystal display cell having a substrate with a transparent electrode prepared by successively depositing the transparent electrode, transparent electrode protective film and alignment film on a substrate, the transparent electrode protective film contains conductive fine particles having 103 to 1012 Ω.cm volume resistivity.

Description

【００３１】
〔ただし、式中、a+bは２〜４であり、aは０〜３であり、bは１〜４であり、Ｒは−Ｃ_nＨ_2n+1（ｎ＝３または４）であり、Ｘは−ＣＨ₃、−ＯＣＨ₃、−Ｃ₂Ｈ₅または−ＯＣ₂Ｈ₅である。Ｍ₁は周期率表第ＩＢ族、第IIＡ、Ｂ族、第III Ａ、Ｂ族、第IVＡ、Ｂ族、第ＶＡ、Ｂ族、第VIＡ族、第VII Ａ族、第VIII族から選ばれる元素またはバナジル（ＶＯ）である。この内、これらの元素などとａ、ｂの好ましい組み合わせは、次表の通りである。〕
【００３２】
【表１】

【００３３】
上記アセチルアセトナトキレート化合物の具体例としては、ジブトキシ−ビスアセチルアセトナトジルコニウム、トリブトキシ−モノアセチルアセトナトジルコニウム、ビスアセチルアセトナト鉛、トリスアセチルアセトナト鉄、ジブトキシ−ビスアセチルアセトナトハフニウム、モノアセチルアセトナト−トリブトキシハフニウムなどが挙げられる。
【００３４】
本発明においては、マトリックス前駆体として上述したアルコキシシラン、金属アルコキシドおよびアセチルアセトナトキレート化合物のそれぞれを単独でまたは２種以上を混合して用いることもできる。
上記マトリックス前駆体成分として、さらに下記化学式（４）で表される繰り返し単位を有するポリシラザンも好ましい。
【００３５】
【化２】

【００３６】
上記式（４）において、Ｒ₁、Ｒ₂およびＲ₃は、それぞれ水素原子または炭素 原子数１〜８のアルキル基であり、アルキル基の中ではメチル基、エチル基またはプロピル基が好ましい。特にＲ₁、Ｒ₂およびＲ₃がいずれも水素原子である場合が好ましく、この場合には、加熱時に分解するアルキル基がなく、加熱時に膜の収縮が少なく、このため収縮ストレス時にクラックが生じることが少なくなり、クラックのほとんどない透明電極保護膜が得られる。
【００３７】
また、上記式（４）で表わされる繰り返し単位を有するポリシラザンは、直鎖状であっても、環状であってもよく、直鎖状のポリシラザンと環状のポリシラザンとが混合して含まれていてもよい。
さらに、このようなポリシラザンの数平均分子量（ポリスチレン換算の分子量）は、５００〜１０，０００、好ましくは１，０００〜４，０００の範囲にあることが望ましい。数平均分子量が５００未満では、加熱硬化時に低分子量のポリシラザンが揮発し、得られる電極保護膜が多孔質になりやすく、また、分子量が１０，０００を越えると、塗布液の流動性が低下する傾向がある。
【００３８】
さらに、上記マトリックス前駆体成分として、一般式Ｒ_nＳｉ(ＯＲ')_4-n（式中、ｎは０〜３の整数、Ｒ、Ｒ'は、互いに同一でも異なっていてもよく、それぞれ炭素数１〜８のアルキル基、アリール基またはビニル基を表わす）で示されるアルコキシシランを加水分解重縮合して得られるシリカゾルと、このアルコキシシランの部分加水分解物との反応物も好ましい。
【００３９】
本発明において透明電極保護膜を形成する際に用いられる被膜形成用塗布液中には、上記マトリックス前駆体成分に加えて、さらに導電性微粒子が含まれている。
このような導電性微粒子として、体積抵抗率が１０³〜１０¹²Ω・ｃｍの導電性を示す微粒子であれば特に限定されるものではなく、前述したと同様の導電性微粒子を用いることができる。具体的には、酸化亜鉛、酸化アンチモン、酸化インジウムなどの導電性無機酸化物微粒子の１種または２種以上を用いることができる。なおこの導電性無機酸化物微粒子は、ＴｉＯ₂−ＳｎＯ₂などのような複合酸化物粒子、あるいは導電性微粒子の外部を絶縁性材料（ＳiＯ₂、有機樹脂など）で被覆した複合型微粒子であってもよい。
【００４０】
これらの導電性微粒子は、被膜形成用塗布液を調製する際に、粉末状またはコロイド粒子が分散したゾルの形態でマトリックスと混合されることが好ましい。またこのような形態で被膜形成用塗布液中に含まれている導電性微粒子の平均粒径は１〜５０ｎｍ、さらに好ましくは１０〜４０ｎｍの範囲である。
導電性微粒子の平均粒子径が上記範囲にあると透明電極膜の表面が１〜１０ｎｍの均一な表面粗さ（Ｒa）を有するので疎水性のポリイミド配向膜などとの密着性に優れている。なお、表面粗さ(Ra)は、JIS B0601-1982によって評価する。
【００４１】
上記のようなマトリックス前駆体および導電性微粒子とを含む被膜形成用塗布液を調製する際には、これらの溶媒または分散媒として水および／または有機溶媒を用いることが好ましい。
このような被膜形成用塗布液を調製する際の有機溶媒としては、アルコール類、エーテル類、ケトン類などから選ばれた通常の有機溶媒が用いられる。これらの有機溶媒は単独でもしくは２種以上を混合して用いてもよい。
【００４２】
本発明で用いられる被膜形成用塗布液中には、マトリックス前駆体および導電性微粒子のような上記成分に加えて、必要に応じて他の成分が添加される。
たとえば平均粒径が５０ｎｍ以下、好ましくは１０〜４０ｎｍの範囲内にある非導電性の無機化合物微粒子が添加された被膜形成用塗布液を用いると、配向膜との密着性に優れた透明電極保護膜を形成することができる。また、これらの無機化合物微粒子の種類を選択することにより透明電極保護膜の屈折率が調節され、透明電極を形成しているＩＴＯ膜などが外部から見えなくすることもできる。
【００４３】
このような配向膜との密着性に優れた透明電極保護膜を形成する際に用いられる無機化合物微粒子としては、具体的には、ＳｉＯ₂、ＴｉＯ₂、ＺｒＯ₂、Ａｌ₂Ｏ₃などの酸化物、またはこれらの₂種以上の混合物もしくは複合酸化物が好ましく用いられる。またこの無機化合物微粒子は、球状または球状に近い形状であることが好ましい。
【００４４】
またこのような非導電性の無機化合物微粒子は、水または有機溶媒に分散したゾルの状態で用いることが好ましいが、無機化合物微粒子を被膜形成用塗布液中に単分散または単分散に近い状態で分散できればゾル以外の状態にある無機化合物微粒子を用いてもよい。
具体的には、この導電性微粒子は、被膜形成用塗布液中に含まれるマトリックス前駆体の種類、必要に応じて被膜形成用塗布液中に添加される上記のような無機化合物微粒子などの種類および量によって異なり、特に限定されないが、乾固成分の全量に対し酸化物換算で１〜５０重量％、好ましくは５〜３０重量％の範囲で含まれていることが望ましい。
【００４５】
塗布液中に非導電性の無機化合物粒子を含む場合は、乾固成分の全量に対し酸化物換算で、導電性微粒子と無機化合物粒子の合計量が５〜７０重量％の範囲にあることが好ましい。
また、被膜形成用塗布液中の固形分濃度は、３〜１５重量％の範囲にあることが好ましい。被膜形成用塗布液中のマトリックス前駆体の濃度は、酸化物換算で１〜１４重量％の範囲にあることが望ましい。
【００４６】
なお、被膜形成用塗布液中のマトリックス前駆体として上記アルコキシシラン、金属アルコキシド、アセチルアセトナトキレート化合物のような加水分解性化合物を用いた場合、この被膜形成用塗布液の水分濃度は、０.１〜４０重量％の範囲であることが好ましい。
上記のような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、フレキソ印刷などの方法で基板上に形成された透明電極の表面に塗布し、次いで透明電極表面に形成された被膜を常温〜９０℃で乾燥し、さらに２００℃以上、好ましくは３００℃以上に加熱して硬化するなどの方法により、上記特定の表面抵抗を有する透明電極保護膜が形成される。
【００４７】
さらにこの透明電極表面に形成されている透明電極保護膜には、好ましくは次のような方法で硬化促進処理が行なわれる。
すなわち、上記塗布工程または乾燥工程の後に、あるいは乾燥工程中に、未硬化段階の被膜に可視光線よりも波長の短い電磁波を照射するかあるいは未硬化段階の被膜を硬化反応を促進するガス雰囲気中に晒す。
【００４８】
このような加熱前の未硬化段階の被膜に照射する電磁波としては、具体的には紫外線、電子線、Ｘ線、γ線などが例示されるが、紫外線が好ましい。たとえば、発光強度が約２５０ｎｍと３６０ｎｍとにおいて極大となり、光強度が１０ｍＷ／ｃｍ²以上である高圧水銀ランプを紫外線源として使用し、１００ｍＪ／ｃｍ²以上、好ましくは１０００ｍＪ／ｃｍ²以上のエネルギー量の紫外線を未硬化段階の被膜に照射すると、未硬化段階の被膜の硬化反応が促進される。
【００４９】
また、加熱前の未硬化段階の被膜の硬化反応を促進するガスとしては、たとえばアンモニア、オゾンなどが例示される。またこのようなガス雰囲気による被膜の硬化促進は、未硬化段階の被膜を、ガス濃度が１００〜１００，０００ｐｐｍ、好ましくは１０００〜１０，０００ｐｐｍであるような上記活性ガス雰囲気下で、１〜６０分処理することによって達成される。
【００５０】
上述したような硬化促進処理を行うと、被膜中にマトリックス前駆体成分として用いられているアルコキシシラン、金属アルコキシド、アセチルアセトナトキレート化合物などの重合が促進されると同時に、被膜中に残存する水および溶媒の蒸発も促進される。このため、次の加熱工程において必要とされる加熱温度、加熱時間などの加熱硬化条件が緩和され、本発明に係る被膜付基材の製造を有利に進めることができる。
【００５１】
また、このガス処理は、加熱硬化後に行っても同様の効果が得られる。
【００５２】
【発明の効果】
本発明に係る液晶表示セルは、特定範囲の体積抵抗率を有する導電性微粒子を含む透明電極保護膜が透明電極付基板と配向膜との間に設けられているので、上下電極間が導通すること等もなく、また配向膜にラビング処理を行なう際に発生する静電気がこの透明電極保護膜を通してすみやかに除去されて配向膜の帯電を防止することができる。
【００５３】
本発明に係る液晶表示セルの製造方法によれば、基板上に透明電極、特定範囲の体積抵抗率を有する導電性微粒子を含む透明電極保護膜および配向膜が互いに密着性よく順次積層された透明電極付基板を備えた液晶表示セルが得られる。
このため本発明によれば、配向膜の帯電に起因する配向膜の破壊および液晶表示セル中での液晶の配向不良が防止される。
【００５４】
さらに、本発明では、透明電極保護膜が特定範囲の平均粒子径を有する導電性微粒子と必要に応じて特定範囲の平均粒子径を有する非導電性無機化合物粒子を含んでいるので表面粗さが微細且つ均一である。このため透明電極保護膜の表面に形成される配向膜は密着性に優れ、しかも、液晶を異常配向させるほどの傷のない配向膜が得られる。したがって本発明によれば、表示画像の色むらが改善された液晶表示セルが提供される。
【００５５】
また、本発明に係る液晶表示セルは、透明電極保護膜の抵抗が従来の絶縁膜に比べて小さいため、表示回路のインピーダンスが下がり、その結果、液晶セルの駆動電圧を下げることもできる。
【００５６】
【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。
【００５７】
【実施例１】
シリカゾルＡ（ヘキシレングリコール中に平均粒径５nmのシリカ微粒子をＳｉＯ₂濃度で１０重量％含むシリカゾル）を６０ｇ、エチルシリケート２８（多摩化学工業社製エチルシリケート、ＳｉＯ₂濃度：２８重量％）２１．４ｇ混合し１０分攪拌した後、ヘキシレングリコール１８５ｇ、６１％硝酸０．２ｇおよび純水１４ｇを添加し，さらにヘキシレングリコール中に平均粒径２０nmのＳｂ₂Ｏ₅・ｎＨ₂Ｏ微粒子を固形分濃度で１０重量％含む導電性微粒子分散ゾル１２０ｇを加えて３時間撹拌し液Ｂを調製した。ジイソプロポキシ-ジオクチルオキシチタニウムのイソプロピルアルコール溶液（ＴｉＯ₂濃度：１０重量％）３００ｇ、トリブトキシ-モノアセチルアセトナトジルコニウムのブタノール溶液（ＺｒＯ₂濃度：１３．５%）４４．４ｇ、ヘキシレングリコール２５５ｇの混合物を液Ｂに加えて４８時間攪拌し、無機酸化物換算で固形分濃度６重量％の透明電極保護膜形成用塗布液を得た。
【００５８】
ガラス基板上にＩＴＯからなる透明電極をドットマトリックスセルが構成できるようにパターン状に形成された透明電極付基板（旭硝子社製３０Ωタイプ）上に、得られた透明電極保護膜形成用塗布液をフレキソ印刷法で塗布し、得られた塗膜を１００℃で乾燥した後、高圧水銀ランプで６，０００ｍＪ／ｃｍ²の紫外線を照射し、次いで３００℃で３０分間焼成することにより透明電極保護膜（１）を形成した。得られた透明電極保護膜（１）の膜厚は触針式段差計サーフコム（東京精密社製）で測定した。
【００５９】
結果を表２に示す。
この透明電極保護膜（１）上にポリイミド樹脂で膜厚約５０nmの配向膜を形成した後、得られた配向膜に２５℃、相対湿度約３０％の条件下でラビング処理を行なった。
こうしてガラス基板上に透明電極、透明電極保護膜（１）および配向膜が順次積層され、かつ配向膜がラビング処理された一対の透明電極付基板を得た。
【００６０】
得られた一対の透明電極付基板を、透明電極同士が互いに対向するように複数のスペーサー粒子を介して離間させたままシーリング剤で固定し、ＳＴＮ液晶を封入した後に液晶の封入口をＵＶ硬化樹脂で封止し、その後１２０℃で１時間の加温処理を経て液晶表示セルを作成した。
線痕の測定
得られた液晶表示セルに静電ガンを用いて静電気を液晶表示セルに印加し（液晶表示セルを帯電させ）、表示画面上に透明電極配線に沿って現れる線状軌跡（線痕）の消失程度の確認を実施した。この線痕は、一部の透明電極配線に静電気が導入されることで、透明電極―絶縁膜―配向膜−液晶層の各誘電体層やそれらの界面に静電気が帯電し、その電荷の影響をうけて液晶が異常配向することによって生じる。
【００６１】
その結果を表２に併記する。
なお上記線痕については、次のような評価を行なった。
○ …線痕が２秒以内で消失
△ …線痕が２秒から３０秒で消失
× …線痕が３０秒以上で消失
ラビング傷の有無の観察
また、得られた液晶表示セルにＤＣ電圧を印加し液晶表示セルに観察されるラビング方向に沿った傷の有無を調べた。この傷は透明電極保護膜と配向膜との密着性を知る上での目安となる。すなわち、透明電極保護膜と配向膜との密着性が悪いと、配向膜にラビング処理を行なう際に配向膜に傷が付くことがある。配向膜に傷があると、液晶表示装置の作動中にこの傷が表示画面に観察され、表示上の不具合になることがあり、これはＤＣ電圧の印加により目視観察で容易に判定できる。
【００６２】
上下伝導性の評価
上下導通性等の評価については，まず上記のドットマトリックスタイプ液晶表示セルの作成工程中において、透明電極保護膜と配向膜を有する基材上に通常の絶縁性スペーサー粒子を散布した後に、その平均粒径より１.５μmほど大きい弾性型のAuメッキスペーサ粒子（ＥW-P触媒化成工業製）を５〜１０個／mm²程度散布し，その後は通常のプロセスで液晶表示セルを作成した。所定の電圧で表示画素部を全面点灯させた場合に、セル内部に混入させたAuメッキスペーサ−粒子に起因する上下透明電極の短絡による表示不良の程度を確認した。
【００６３】

表面抵抗および耐電圧の半減期の測定
また、透明電極を形成しないアルカリパッシベーション膜（ＳｉＯ₂スパッタ）付ガラス基板上に上記した成膜方法で透明電極保護膜（２）を形成し，その基材の表面抵抗を表面抵抗計ハイレスタ（三菱油化社製）を用いて測定した。また、同一基材の帯電圧の半減期を帯電減衰装置（静電式スイープメモリーKM-511，春日電気（株）社製）を用いて測定した。
【００６４】
屈折率の測定
さらに、シリコンウェハー上に同様な成膜方法で透明電極保護膜（３）を形成させ，エリプソメータを用いてその屈折率を測定した。
結果を表２に示す。
【００６５】
【実施例２】
シリカゾルＣ（ヘキシレングリコール中に平均粒径４５ｎｍのシリカ微粒子をＳｉＯ₂濃度で１０重量％含むシリカゾル）を３０ｇ、エチルシリケート２８（ＳｉＯ₂濃度：２８重量％）を９６．４ｇ、γ-グリシドキシプロピルトリメトキシシラン（ＳｉＯ₂濃度：２５．４重量％）７０．９ｇを混合し２０分攪拌した後に、ヘキシレングリコール６６４．５ｇ、濃度６１重量％の硝酸０．２ｇ、純水１８ｇおよびヘキシレングリコール中に平均粒径２０ｎｍのＳｂ₂Ｏ₅・nＨ₂Ｏ微粒子を固形分濃度で１０重量％含む導電性微粒子分散ゾル１２０ｇを加えて１２時間撹拌し、無機酸化物換算で固形分濃度６重量％の透明電極保護膜形成用塗布液を得た。
【００６６】
得られた透明電極保護膜形成用塗布液を用いて、ガラス基板上にＩＴＯからなる透明電極がパターン状に形成された透明電極付基板（旭硝子(株)製：３０Ωタイプ）の電極面上に、フレキソ印刷法で塗布し、得られた塗膜を１００℃で乾燥した後、２００℃で３０分間焼成することにより透明電極保護膜（１）を形成した。
【００６７】
さらに、透明電極パターン上に上記の成膜条件で形成された透明保護膜付き基材を用いて、実施例１と同様な手法で液晶表示セルを作成し、静電気による線痕状態とラビング傷および上下電極の導通についての評価を行った。
また、アルカリパッシベーション膜付きガラス基板、シリコンウェハーにも上記の成膜条件で透明電極保護膜（２）および（３）を形成した。
【００６８】
得られた透明電極保護膜の膜厚（電極保護膜の膜の厚さは保護膜（１）〜（３）でいずれも同一）、表面抵抗、耐電圧の半減期および屈折率を実施例１と同様な手法で測定した。
それらの結果を表２に示す。
【００６９】
【実施例３】
チタニアゾル（ヘキシレングリコール中に平均粒径２０ｎｍのチタニア微粒子をＴｉＯ₂濃度で１０重量％含むチタニアゾル）３０ｇ、エチルシリケート４０（ＳｉＯ₂濃度：４０重量％）３０ｇ、チタンオクチレングリコレートのＩＰＡ溶液（ＴｉＯ₂濃度：９重量％）４００ｇを混合し２０分攪拌した後に、ヘキシレングリコール４３５．８ｇ、濃度６１重量％の硝酸０．２ｇ、および純水１４ｇを添加し、さらにヘキシレングリコール中に平均粒径２０ｎｍのＳｂ₂Ｏ₅・nＨ₂Ｏ微粒子を固形分濃度で１０重量％含む導電性微粒子分散ゾル９０ｇを加えて１２時間撹拌し、固形分濃度６重量％の透明電極保護膜形成用塗布液を得た。
【００７０】
得られた透明電極保護膜形成用塗布液を、ガラス基板上にＩＴＯからなる透明電極がパターン状に形成された透明電極付基板（旭硝子（株）製：３０Ωタイプ）の電極面上に、フレキソ印刷法で塗布し、得られた塗膜を１００℃で乾燥した後、高圧水銀ランプで６，０００ｍＪ／ｃｍ²の紫外線を照射し、次いで３００℃で３０分間焼成することにより透明電極保護膜（１）を形成した。
【００７１】
さらに、透明電極パターン上に上記の成膜条件で形成された透明保護膜付き基材を用いて、実施例１と同様な手法で液晶表示セルを作成し、静電気による線痕状態とラビング傷および上下電極の導通についての評価を行った。
また、アルカリパッシベーション膜付きガラス基板、シリコンウェハーにも上記の成膜条件で透明電極保護膜（２）および（３）を形成した。
【００７２】
得られた透明電極保護膜の膜厚（電極保護膜の膜の厚さは保護膜（１）〜（３）でいずれも同一）、表面抵抗、耐電圧の半減期および屈折率を実施例１と同様な手法で測定した。
それらの結果を表２に示す。
【００７３】
【参考例４】
エチルシリケート２８（ＳｉＯ₂濃度：２８重量％）１５０ｇにブチルセロソルブ４０ｇ、ヘキシレングリコール３０４．４ｇ、濃度６１重量％の硝酸０．４ｇおよび純水１５ｇを添加し、ヘキシレングリコール中に平均粒径２０ｎｍのＳｂ₂Ｏ５・nＨ₂Ｏ微粒子を固形分濃度で１０重量％含む導電性微粒子分散ゾル９０ｇを加えて３時間撹拌し液Ｄを調製した。ジイソプロポキシ-ジオクチルオキシチタニウムのイソプロピルアルコール溶液（ＴｉＯ₂濃度：１０重量％）６０ｇ、トリブトキシ-モノアセチルアセトナトジルコニウムのブタノール溶液（ＺｒＯ₂濃度：１３．５重量％）２２．２ｇ、ヘキシレングリコール３１８ｇの混合物を液Ｄに加えて４８時間攪拌し、無機酸化物換算で固形分濃度６重量％の透明電極保護膜形成用塗布液を得た。
【００７４】
得られた透明電極保護膜形成用塗布液を、ガラス基板上にＩＴＯからなる透明電極がパターン状に形成された透明電極付基板（旭硝子(株)製：３０Ωタイプ）の電極面上に、フレキソ印刷法で塗布し、得られた塗膜を１００℃で乾燥した後、高圧水銀ランプで６,０００ｍＪ／ｃｍ²の紫外線を照射し、次いで３００℃で３０分間焼成することにより透明電極保護膜（１）を形成した。
【００７５】
さらに、透明電極パターン上に上記の成膜条件で形成された透明保護膜付き基材を用いて、実施例１と同様な手法で液晶表示セルを作成し、静電気による線痕状態とラビング傷および上下電極の導通についての評価を行った。
また、アルカリパッシベーション膜付きガラス基板、シリコンウェハーにも上記の成膜条件で透明電極保護膜（２）および（３）を形成した。
【００７６】
得られた透明電極保護膜の膜厚（電極保護膜の膜の厚さは保護膜（１）〜（３）でいずれも同一）、表面抵抗、耐電圧の半減期および屈折率を実施例１と同様な手法で測定した。
それらの結果を表２に示す。
【００７７】
【参考例５】
エチルシリケート２８（ＳｉＯ₂濃度：２８重量％）と１０７．１ｇ、γ-グリシドキシプロピルトリメトキシシラン（ＳｉＯ₂濃度：２５．４重量％）７０．９ｇとを混合し、ヘキシレングリコール６７６．８ｇ、６１％硝酸０．２ｇ、および純水２５ｇを添加した後、３時間攪拌しＥ液を調製した。珪酸液とアンチモン酸カリウムを原料としてあらかじめ調製したＳｂ₂Ｏ₅−ＳｉＯ₂複合型ゾル（平均粒径１５ｎｍ、固形分濃度で１０重量％、ヘキシレングリコール含む導電性微粒子分散ゾル）１２０ｇをＥ液に加えて１２時間撹拌し、無機酸化物換算で固形分濃度６重量％の透明電極保護膜形成用塗布液を得た。
【００７８】
得られた透明電極保護膜形成用塗布液を用いて、ガラス基板上にＩＴＯからなる透明電極がパターン状に形成された透明電極付基板（旭硝子(株)製：３０Ωタイプ）の電極面上に、フレキソ印刷法で塗布し、得られた塗膜を１００℃で乾燥した後、２００℃で３０分間焼成することにより透明電極保護膜（１）を形成した。
【００７９】
さらに、透明電極パターン上に上記の成膜条件で形成された透明保護膜付き基材を用いて、実施例１と同様な手法で液晶表示セルを作成し、静電気による線痕状態とラビング傷および上下電極の導通についての評価を行った。
また、アルカリパッシベーション膜付きガラス基板、シリコンウェハーにも上記の成膜条件で透明電極保護膜（２）および（３）を形成した。
【００８０】
得られた透明電極保護膜の膜厚（電極保護膜の膜の厚さは保護膜（１）〜（３）でいずれも同一）、表面抵抗、耐電圧の半減期および屈折率を実施例１と同様な手法で測定した。
それらの結果を表２に示す。
【００８１】
【比較例１】
エチルシリケート２８（ＳｉＯ₂濃度：２８重量％）８５．７ｇ、ジプロピレングリコール１００ｇ、ヘキシレングリコール２０２ｇ、濃度６１重量％の硝酸０．２ｇおよび純水１２ｇを混合した後、３時間撹拌し液Ｆを調製した。テトラノルマルブチルチタネート（ＴｉＯ₂濃度：２３．５重量％）１２７．７ｇ、ジルコニウムノルマルプロポキシド（ＺｒＯ₂濃度：２８％）２１．４ｇ、ヘキシレングリコール４５１ｇの混合物を液Ｆに加えて４８時間攪拌し、無機酸化物換算で固形分濃度６重量％の透明電極保護膜形成用塗布液を得た。
【００８２】
得られた透明電極保護膜形成用塗布液を、ガラス基板上にＩＴＯからなる透明電極がパターン状に形成された透明電極付基板（旭硝子（株）製：３０Ωタイプ）の電極面上に、フレキソ印刷法で塗布し、得られた塗膜を１００℃で乾燥した後、高圧水銀ランプで６、０００ｍＪ／ｃｍ²の紫外線を照射し、次いで３００℃で３０分間焼成することにより透明電極保護膜を形成した。
【００８３】
さらに、透明電極パターン上に上記の成膜条件で形成された透明保護膜付き基材を用いて、実施例１と同様な手法で液晶表示セルを作成し、静電気による線痕状態とラビング傷および上下電極の導通についての評価を行った。
また、アルカリパッシベーション膜付きガラス基板、シリコンウェハーにも上記の成膜条件で透明電極保護膜（２）および（３）を形成した。
【００８４】
得られた透明電極保護膜の膜厚（電極保護膜の膜の厚さは保護膜（１）〜（３）でいずれも同一）、表面抵抗、耐電圧の半減期および屈折率を実施例１と同様な手法で測定した。
それらの結果を表２に示す。
【００８５】
【比較例２】
エチルシリケート２８（ＳｉＯ₂濃度：２８重量％）８５．７ｇ、ヘキシレングリコール３７４ｇ、６１％硝酸０．３ｇおよび純水２０ｇを混合した後に１時間攪拌を行い、ヘキシレングリコール中に平均粒径１０nmの酸化スズ微粒子を固形分濃度で１０重量％分散して含む導電性微粒子分散ゾル１２０ｇを加えて１２時間撹拌し液Ｇを調製した。ジイソプロポキシ-ジオクチルオキシチタニウムのイソプロピルアルコール溶液（ＴｉＯ₂濃度：１０重量％）２４０ｇ、ヘキシレングリコール１６０ｇの混合物を液Ｆに加えて４８時間攪拌し、無機酸化物換算で固形分濃度６重量％の透明電極保護膜形成用塗布液を得た。
【００８６】
得られた透明電極保護膜形成用塗布液を、ガラス基板上にＩＴＯからなる透明電極がパターン状に形成された透明電極付基板（旭硝子（株）製：３０Ωタイプ）の電極面上に、フレキソ印刷法で塗布し、得られた塗膜を１００℃で乾燥した後、高圧水銀ランプで６、０００ｍＪ／ｃｍ²の紫外線を照射し、次いで３００℃で３０分間焼成することにより透明電極保護膜（１）を形成した。
【００８７】
さらに、透明電極パターン上に上記の成膜条件で形成された透明保護膜付き基材を用いて、実施例１と同様な手法で液晶表示セルを作成し、静電気による線痕状態とラビング傷および上下電極の導通についての評価を行った。
また、アルカリパッシベーション膜付きガラス基板、シリコンウェハーにも上記の成膜条件で透明電極保護膜（２）および（３）を形成した。
【００８８】
得られた透明電極保護膜の膜厚（電極保護膜の膜の厚さは保護膜（１）〜（３）でいずれも同一）、表面抵抗、耐電圧の半減期および屈折率を実施例１と同様な手法で測定した。
それらの結果を表２に示す。
【００８９】
【比較例３】
シリカゾルＡ（ヘキシレングリコール中に平均粒径５nmのシリカ微粒子をＳｉＯ₂濃度で１０重量％含むシリカゾル）６０ｇ、エチルシリケートエチルシリケート２８（ＳｉＯ₂濃度：２８重量％）８５．７ｇ、メチルトリメトキシシラン（ＳｉＯ₂濃度：４４重量％）４０．９ｇの混合液に、ヘキシレングリコール６７３．１ｇ、濃度６１重量％の硝酸０．３ｇ、純水２０ｇ、およびヘキシレングリコール中に平均粒径１０ｎｍのアンチモンがドープされた酸化スズ微粒子を固形分濃度で１０重量％分散して含む導電性微粒子分散ゾル１２０ｇを加えて１２時間撹拌し、無機酸化物換算で固形分濃度６重量％の透明電極保護膜形成用塗布液を得た。
【００９０】
得られた透明電極保護膜形成用塗布液を用いて、ガラス基板上にＩＴＯからなる透明電極がパターン状に形成された透明電極付基板（旭硝子（株）製：３０Ωタイプ）の電極面上に、フレキソ印刷法で塗布し、得られた塗膜を１００℃で乾燥した後、２００℃で３０分間焼成することにより透明電極保護膜（１）を形成した。
【００９１】
さらに、透明電極パターン上に上記の成膜条件で形成された透明保護膜付き基材を用いて、実施例１と同様な手法で液晶表示セルを作成し、静電気による線痕状態とラビング傷および上下電極の導通についての評価を行った。
また、アルカリパッシベーション膜付きガラス基板、シリコンウェハーにも上記の成膜条件で透明電極保護膜（２）および（３）を形成した。
【００９２】
得られた透明電極保護膜の膜厚（電極保護膜の膜の厚さは保護膜（１）〜（３）でいずれも同一）、表面抵抗、耐電圧の半減期および屈折率を実施例１と同様な手法で測定した。
それらの結果を表２に示す。
【００９３】
【比較例４】
シリカゾルＨ（ヘキシレングリコール中に平均粒径２５ｎｍのシリカ微粒子をＳｉＯ₂濃度で１０重量％含むシリカゾル）１２０ｇ、エチルシリケート２８（ＳｉＯ₂濃度：２８重量％）６４．３ｇ、γ-グリシドキシプロピルトリメトキシシラン（ＳｉＯ₂濃度：２５．４重量％）１１８．１ｇの混合物に、ヘキシレングリコール６８２．４ｇ、濃度６１重量％の硝酸０．２ｇおよび純水１５ｇを添加し１２時間撹拌した後、固形分濃度６重量％の透明電極保護膜形成用塗布液を得た。
【００９４】
得られた透明電極保護膜形成用塗布液を用いて、ガラス基板上にＩＴＯからなる透明電極がパターン状に形成された透明電極付基板（旭硝子（株）製：３０Ωタイプ）の電極面上に、フレキソ印刷法で塗布し、得られた塗膜を１００℃で乾燥した後、２００℃で３０分間焼成することにより透明電極保護膜（１）を形成した。
【００９５】
さらに、透明電極パターン上に上記の成膜条件で形成された透明保護膜付き基材を用いて、実施例１と同様な手法で液晶表示セルを作成し、静電気による線痕状態とラビング傷および上下電極の導通についての評価を行った。
また、アルカリパッシベーション膜付きガラス基板、シリコンウェハーにも上記の成膜条件で透明電極保護膜（２）および（３）を形成した。
【００９６】
得られた透明電極保護膜の膜厚（電極保護膜の膜の厚さは保護膜（１）〜（３）でいずれも同一）、表面抵抗、耐電圧の半減期および屈折率を実施例１と同様な手法で測定した。
【００９７】
【表２】

【図面の簡単な説明】
【図１】本発明に係る液晶表示セルを模式的に表す断面図である。
【図２】単分散性の悪い導電性微粒子の保護膜中での分布状態を示す模式図を示す。
【符号の説明】
１…液晶表示セル
２、２'…透明電極付基板
３…スペーサー粒子
４…液晶
２１…透明基板
２２…透明電極膜
２３…透明電極保護膜
２４…配向膜
ｄ…間隔[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a liquid crystal display cell including a substrate with a transparent electrode in which a transparent electrode, a transparent electrode protective film, and an alignment film are sequentially laminated on the substrate, and a method for manufacturing the same. A liquid crystal display cell comprising a substrate with a transparent electrode on which a transparent electrode protective film is formed so that static electricity generated in the alignment film can be quickly removed when the film is rubbed and the alignment film can be prevented from being charged. It relates to a manufacturing method.
[0002]
TECHNICAL BACKGROUND OF THE INVENTION
Conventionally, a transparent electrode such as ITO and an alignment film made of a polymer such as polyimide are sequentially laminated on the surface of a glass substrate, and a pair of transparent electrode-attached substrates is provided so that the transparent electrode films face each other. There is known a liquid crystal display cell in which liquid crystal is sealed in a gap formed at a predetermined interval by the spacer.
[0003]
In this type of liquid crystal display cell, the alignment film may be damaged by foreign matters or spacers mixed in the liquid crystal. As a result, the upper and lower electrodes are electrically connected, and display defects may occur.
Further, static electricity is generated when the alignment film is rubbed, and the static electricity is instantaneously discharged in large quantities through the transparent electrode, and the alignment film may be heated and destroyed in the discharge process.
[0004]
For this reason, conventionally, it has been proposed to form an insulating protective film between the transparent electrode and the alignment film on the substrate with the transparent electrode of the liquid crystal display cell as described above (Japanese Patent Laid-Open No. Sho 60-60). No. 260021, JP-A-1-150116, JP-A-2-221923, etc.).
However, if such an insulating film is formed between the transparent electrode and the alignment film, static electricity charged in the alignment film during rubbing cannot be removed, and static electricity remains in the alignment film. For this reason, a liquid crystal display cell including a substrate with a transparent electrode in which a transparent electrode, an insulating film, and an alignment film are sequentially laminated on the substrate has a problem that a display defect occurs.
[0005]
Japanese Patent Laid-Open No. 4-37714 discloses that surface resistance is 10 by sputtering tin oxide on the transparent electrode forming surface or by applying a coating solution containing tin oxide-based fine particles.⁸-10¹³It is disclosed that a thin film layer of Ω / □ is formed.
Furthermore, the applicant of the present application disclosed in Japanese Patent Laid-Open No. 5-232459 contains conductive fine particles and inorganic compound particles, and has a surface resistance of 10⁹-10¹³It has been proposed that a transparent electrode protective film of Ω / □ solves the above problems and has excellent adhesion to the electrode film and the alignment film.
[0006]
By the way, when an insulating thin film is formed on a transparent electrode of a liquid crystal panel, the film thickness is 150 nm or less, preferably 100 nm or less, from the viewpoint of preventing delay of electric signals and reducing voltage loss (reducing power consumption). There is a need. The surface resistance is 10⁸-10¹²Similarly, when an Ω / □ insulating thin film is formed, the upper limit of the film thickness is restricted.
[0007]
The tin oxide disclosed in the above-mentioned JP-A-4-37714 is generally 10²It exhibits a volume resistance of about Ω · cm or less and high electrical conductivity. Using such conductive fine particles (such as tin oxide), the surface resistance is 10⁸-10¹²When an insulating thin film having a film thickness of Ω / □ is formed and the conductive fine particles in the thin film are dispersed in the thin film, for example, as shown in FIG. In some cases, the monodispersity is not sufficient, so that the insulation is insufficient, and vertical conduction (electric leakage) is likely to occur.
[0008]
Furthermore, a liquid crystal display device in which an insulating thin film is formed from fine particles having high electrical conductivity such as tin oxide-based fine particles may contain conductive foreign matters inside the insulating thin film during the manufacturing process. There is also a problem in that the liquid crystal display device malfunctions due to an electrical short circuit between the upper and lower transparent electrodes caused by the conductive foreign matter.
[0009]
OBJECT OF THE INVENTION
The present invention is intended to solve the above-described problems in the prior art, and has excellent adhesion to the electrode film and the alignment film, and static electricity generated in the alignment film when the alignment film is rubbed. To provide a liquid crystal display cell including a substrate with a transparent electrode on which a transparent electrode protective film on which an alignment film can be prevented and charging of an alignment film can be prevented without causing an insulation failure, and a method for manufacturing the same It is an object.
[0010]
SUMMARY OF THE INVENTION
  The liquid crystal display cell according to the present invention is a liquid crystal display cell comprising a substrate with a transparent electrode in which a transparent electrode, a transparent electrode protective film and an alignment film are sequentially laminated on the substrate.Film thickness 20 ~ 150nm In the range ofVolume resistivity is 10^Three-10¹²In the range of Ω · cmYes, antimonic acid (S b ₂ O _Five ・ NH ₂ O: n is 0 . 02-4), and the average particle size is 1-50 nm ofConductive fine particles1 to 50% by weight,
  And an average particle size of 2 to 200 nm Non-conductive inorganic compound particles of conductive fine particles and SiO ₂ TiO ₂ , ZrO ₂ , Al ₂ O _Three The total amount of the conductive fine particles and the non-conductive inorganic compound particles is 5 to 70% by weight in terms of oxides. In the amount of%It is characterized by comprising.
[0011]
  The liquid crystal display cell manufacturing method according to the present invention is formed on a substrate when manufacturing a liquid crystal display cell including a substrate with a transparent electrode in which a transparent electrode, a transparent electrode protective film, and an alignment film are sequentially laminated on the substrate. On the surface of the transparent electrode, the volume resistivity is 10^Three-10¹²In the range of Ω · cmYes, antimonic acid (S b ₂ O _Five ・ NH ₂ O: n is 0 . 02-4)Conductive fine particles1 to 50% by weight in terms of oxide with respect to the total amount of dry components, SiO ₂ TiO ₂ , ZrO ₂ , Al ₂ O _Three Such as oxide, or these 2 The amount of the conductive fine particles and the non-conductive inorganic compound particles is 5 to 70% by weight in terms of oxide with respect to the total amount of the dry solid components of the non-conductive inorganic compound particles composed of a mixture of at least seeds or the composite oxide. ,And matrix precursorsIn an amount of 1 to 14% by weight in terms of oxideIt is characterized by including a step of applying the contained coating forming coating solution and curing the resulting coating to form a transparent electrode protective film.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the liquid crystal display cell and the manufacturing method thereof according to the present invention will be specifically described.
First, a liquid crystal display cell according to the present invention will be specifically described with reference to the drawings.
FIG. 1 is a cross-sectional view schematically showing an example of a liquid crystal display cell according to the present invention.
[0014]
In the liquid crystal display cell 1, a transparent electrode 22 such as an ITO thin film, a transparent electrode protective film 23, and an alignment film 24 made of a polymer such as polyimide are sequentially laminated on a transparent substrate 21 such as glass or plastic. A pair of transparent electrode-equipped substrates 2 and 2 ′ is provided. The pair of substrates 2 and 2 ′ with transparent electrodes are arranged with a plurality of spacer particles 3 with a gap d of a predetermined interval so that the transparent electrodes 22 and 22 face each other. Further, the liquid crystal 4 is sealed in the gap d.
[0015]
In the substrate with transparent electrode 2 according to the present invention, the volume resistivity is 10 between the transparent electrode 22 and the alignment film 24 of the substrate with transparent electrode 2.^Three-10¹²Ω · cm, preferably 10^Five-10^TenA transparent electrode protective film 23 containing conductive fine particles in the range of Ω · cm is formed. The transparent electrode protective film 23 containing such conductive fine particles has an insulation property that does not allow conduction between the upper and lower electrodes even if the alignment film is damaged by foreign matters or spacers mixed in the liquid crystal 4. The static electricity generated when the alignment film 24 is rubbed is quickly removed without charging the alignment film 24, and the display film has conductivity sufficient to prevent unevenness of the display image due to the static electricity charged on the alignment film 24. is doing.
[0016]
The volume resistivity of the conductive fine particles contained in the transparent electrode protective film 23 is 10¹²If it exceeds Ω · cm, the surface resistance of the transparent electrode protective film is 10¹³In some cases, Ω / □ may be exceeded, and it becomes difficult to remove static electricity charged in the alignment film 24. On the other hand, the volume resistivity of the conductive fine particles contained in the transparent electrode protective film 23 is 10^ThreeIf it is less than Ω · cm, the surface resistance of the transparent electrode protective film described later is 10⁹-10¹³Even in the range of Ω / □, depending on the distribution state of the conductive fine particles in the protective film, the insulating property may be insufficient, and the upper and lower transparent electrodes may be electrically connected. For example, in the case of a dot matrix display cell between adjacent segment electrodes, conduction between adjacent line electrodes or a short circuit between upper and lower electrodes occurs when the alignment film is damaged, resulting in normal display. It may not be possible.
[0017]
The film thickness of the transparent electrode protective film 23 is preferably in the range of 20 to 150 nm, more preferably in the range of 30 to 100 nm.
If the film thickness of the transparent electrode protective film is in the above range, the effect of the liquid crystal display device on the delay of the electric signal and the decrease in the driving voltage loss is improved, and an excellent liquid crystal display device is obtained. Such conductive fine particles have a volume resistivity of 10^Three-10¹²If it exists in the range of (omega | ohm) * cm, there will be no restriction | limiting in particular, It can use.
[0018]
Specifically, at least one kind of conductive inorganic oxide fine particles such as zinc oxide, antimony oxide, and indium oxide can be used. The conductive inorganic oxide fine particles are made of TiO.₂-SnO₂Insulating material (SiO 2)₂Or composite type fine particles coated with an organic resin or the like.
[0019]
Among these conductive inorganic oxide fine particles, among antimony oxides, antimony pentoxide, especially antimonic acid (Sb) having a crystal water and having a pyrochlore structure.₂O_Five・ NH₂O: n is 0.02 to 4), and the upper and lower electrodes do not conduct even when the alignment film is damaged, and the static electricity generated when the alignment film is rubbed is not charged. In addition, since it has ion exchange capability, it can absorb and reduce mobile ions (ionic impurities) in the liquid crystal, so that the TFT-type liquid crystal display device can have high voltage retention characteristics. In addition, in the STN type liquid crystal display device, display defects due to movable ions can be suppressed, and power consumption can be reduced. The antimonic acid is described in detail in Journal of Chemical Society of Japan (No. 4, page 488, 1983).
[0020]
The conductive fine particles have an average particle diameter in the range of 1 to 50 nm, more preferably 10 to 40 nm.
When the average particle diameter of the conductive fine particles is within the above range, the surface of the transparent electrode film has a uniform surface roughness (Ra) of 1 to 10 nm, so that it has excellent adhesion to a hydrophobic polyimide alignment film and the like, and has an insulating property. The transparency of the thin film is not impaired.
[0021]
The content of such conductive fine particles in the transparent electrode protective film varies depending on the type of matrix contained in the transparent electrode protective film and the type and amount of non-conductive inorganic compound particles to be described later added as necessary. Although not particularly limited, with respect to the total weight when the transparent electrode protective film is represented by oxides and nitrides, the conductive fine particles are in the range of 1 to 50% by weight, preferably 5 to 30% by weight in terms of oxides. It is desirable to include. If the conductive fine particles are contained within such a range, defects that cause electrical leakage between the transparent electrodes are reduced, and static electricity generated when the alignment film is rubbed is not charged.
[0022]
Such a transparent electrode protective film preferably further contains non-conductive inorganic compound particles.
As non-conductive inorganic compound particles, specifically, SiO₂TiO₂, ZrO₂, Al₂O_ThreeAn oxide such as, or a mixture or composite oxide of two or more of these is preferably used. The non-conductive inorganic compound particles are preferably spherical or nearly spherical. The average particle size of such non-conductive inorganic compound particles is in the range of 2 to 200 nm, more preferably 5 to 50 nm.
[0023]
When the non-conductive inorganic compound particles are included, the transparent electrode protective film is included so that the total amount of the conductive fine particles and the non-conductive inorganic compound particles is in the range of 5 to 70% by weight in terms of oxide. It is preferable. When non-conductive inorganic compound particles are included in such a range, a transparent electrode protective film excellent in adhesion to the alignment film can be obtained regardless of the content of the conductive fine particles, the average particle diameter, etc. The antistatic performance (surface resistance), refractive index, etc. of the electrode protective film can be controlled to a desired level.
[0024]
In the liquid crystal display cell according to the present invention, SiO 2 is further interposed between the glass substrate 21 and the transparent electrode film 22.₂It is also possible to use a substrate with a transparent electrode on which an alkali passivation film such as a film is formed.
The liquid crystal display cell according to the present invention as described above is manufactured by, for example, the following manufacturing method.
[0025]
The method for manufacturing a liquid crystal display cell according to the present invention has a volume resistivity of 10 on the surface of a transparent electrode formed on a substrate.^Three-10¹²The method includes a step of applying a coating forming coating solution containing conductive fine particles and a matrix precursor in the range of Ω · cm, and curing the obtained coating to form a transparent electrode protective film.
The coating solution for forming a film used for forming the transparent electrode protective film as described above is not particularly limited as long as it is a coating solution containing conductive fine particles and a matrix precursor, but water and / or an organic solvent. A coating liquid for forming a film in which a matrix precursor and conductive fine particles are dispersed is preferable.
[0026]
The matrix precursor used in preparing the coating liquid for forming a film is not particularly limited as long as it has film-forming properties. However, one of these components or the following compound or a condensate thereof is used as a component: It is preferable to consist of two or more.
As the matrix precursor component as described above, the following chemical formula (1)
R_aSi (OR ')_4-a                                  ... (1)
Wherein R is -C_nH_{2n + 1}And R ′ is —C_nH_{2n + 1}Or -C₂H_FourOC_nH_{2n + 1}A is an integer of 0 to 3, and n is an integer of 1 to 4. )
It is preferable to use an alkoxysilane represented by
[0027]
Specific examples of the alkoxysilane include tetramethoxysilane, tetraethoxysilane, monomethyltrimethoxysilane, monoethyltriethoxysilane, monoethyltrimethoxysilane, monomethyltriethoxysilane, and the like.
The alkoxysilane may be used as it is, or may be used after partial hydrolysis. Such partial hydrolysis of alkoxysilane is carried out according to a conventional method, for example, a method in which alkoxysilane is mixed with alcohol such as methanol or ethanol, and water and an acid are added to perform partial hydrolysis. Can do.
[0028]
Further, as the matrix precursor component, a metal alkoxide represented by the following chemical formula (2) or a condensate thereof can also be suitably used.
M (OR)_n                                          ... (2)
Wherein M is a metal atom, R is an alkyl group or —C_mH_2mOC_lH_{2l + 1}(M is 3 to 10, l is 1 to 4, and n is the same integer as the valence of M.)
In the above formula (2), M is not particularly limited as long as it is a metal, but preferable M is Be, Al, Sc, Ti, V, Cr, Fe, Ni, Zn, Ga, Ge, As, Se, Y, Zr, Nb, In, Sn, Sb, Te, Hf, Ta, W, Pb, Bi, Ce, or Cu.
[0029]
As such a metal alkoxide, specifically, tetrabutoxyzirconium, diisopropoxy-dioctyloxytitanium, diethoxylead and the like are preferably used.
Furthermore, an acetylacetonato chelate compound represented by the following chemical formula (3) or a condensate thereof is also preferable as the matrix precursor component.
[0030]
[Chemical 1]

[0031]
[Wherein, a + b is 2 to 4, a is 0 to 3, b is 1 to 4, and R is —C_nH_{2n + 1}(N = 3 or 4) and X is —CH_Three, -OCH_Three, -C₂H_FiveOr -OC₂H_FiveIt is. M₁Is an element selected from Group IB, Group IIA, Group B, Group IIIA, Group B, Group IVA, Group B, Group VA, Group B, Group VIA, Group VIIA, Group VIII or Vanadyl (VO). Among these, preferred combinations of these elements and a and b are as shown in the following table. ]
[0032]
[Table 1]

[0033]
Specific examples of the acetylacetonato chelate compound include dibutoxy-bisacetylacetonatozirconium, tributoxy-monoacetylacetonatozirconium, bisacetylacetonatolead, trisacetylacetonatoiron, dibutoxy-bisacetylacetonatohafnium, monoacetyl And acetonato-tributoxyhafnium.
[0034]
In the present invention, the above-mentioned alkoxysilane, metal alkoxide and acetylacetonato chelate compound can be used alone or in admixture of two or more as the matrix precursor.
As the matrix precursor component, polysilazane having a repeating unit represented by the following chemical formula (4) is also preferable.
[0035]
[Chemical 2]

[0036]
In the above formula (4), R₁, R₂And R_ThreeAre each a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, and among the alkyl groups, a methyl group, an ethyl group or a propyl group is preferred. Especially R₁, R₂And R_ThreeAre preferably hydrogen atoms. In this case, there is no alkyl group that decomposes during heating, and there is little shrinkage of the film during heating, so that cracks are less likely to occur during shrinkage stress, and there are almost no cracks. A transparent electrode protective film is obtained.
[0037]
The polysilazane having a repeating unit represented by the above formula (4) may be linear or cyclic, and contains a mixture of linear polysilazane and cyclic polysilazane. Also good.
Furthermore, the number average molecular weight (polystyrene equivalent molecular weight) of such polysilazane is desirably in the range of 500 to 10,000, preferably 1,000 to 4,000. When the number average molecular weight is less than 500, the low molecular weight polysilazane volatilizes at the time of heat curing, and the resulting electrode protective film is likely to be porous, and when the molecular weight exceeds 10,000, the fluidity of the coating solution decreases. Tend.
[0038]
Further, as the matrix precursor component, the general formula R_nSi (OR ')_4-n(Wherein n is an integer of 0 to 3, and R and R ′ may be the same or different from each other, and each represents an alkyl group, aryl group or vinyl group having 1 to 8 carbon atoms) A reaction product of a silica sol obtained by hydrolytic polycondensation of this and a partial hydrolyzate of this alkoxysilane is also preferred.
[0039]
In the coating liquid for forming a film used for forming the transparent electrode protective film in the present invention, conductive fine particles are further contained in addition to the matrix precursor component.
As such conductive fine particles, the volume resistivity is 10^Three-10¹²There is no particular limitation as long as it is a fine particle exhibiting conductivity of Ω · cm, and conductive fine particles similar to those described above can be used. Specifically, one kind or two or more kinds of conductive inorganic oxide fine particles such as zinc oxide, antimony oxide, and indium oxide can be used. The conductive inorganic oxide fine particles are made of TiO.₂-SnO₂Insulating materials (SiO₂Or composite type fine particles coated with an organic resin or the like.
[0040]
These conductive fine particles are preferably mixed with the matrix in the form of a sol in which powder or colloidal particles are dispersed when preparing a coating liquid for forming a film. Moreover, the average particle diameter of the electroconductive fine particles contained in the coating liquid for forming a film in such a form is in the range of 1 to 50 nm, more preferably 10 to 40 nm.
When the average particle diameter of the conductive fine particles is within the above range, the surface of the transparent electrode film has a uniform surface roughness (Ra) of 1 to 10 nm, and thus has excellent adhesion to a hydrophobic polyimide alignment film or the like. The surface roughness (Ra) is evaluated according to JIS B0601-1982.
[0041]
When preparing a coating liquid for forming a film containing the matrix precursor and the conductive fine particles as described above, it is preferable to use water and / or an organic solvent as the solvent or dispersion medium.
As an organic solvent for preparing such a coating liquid for forming a film, an ordinary organic solvent selected from alcohols, ethers, ketones and the like is used. These organic solvents may be used alone or in admixture of two or more.
[0042]
In addition to the above components such as the matrix precursor and conductive fine particles, other components are added to the coating liquid for forming a film used in the present invention as necessary.
For example, when a coating liquid for forming a film to which non-conductive inorganic compound fine particles having an average particle diameter of 50 nm or less, preferably 10 to 40 nm are added, is used, the transparent electrode can be protected with excellent adhesion to the alignment film. A film can be formed. Further, by selecting the kind of these inorganic compound fine particles, the refractive index of the transparent electrode protective film is adjusted, and the ITO film or the like forming the transparent electrode can be made invisible from the outside.
[0043]
As inorganic compound fine particles used when forming a transparent electrode protective film excellent in adhesion to such an alignment film, specifically, SiO₂TiO₂, ZrO₂, Al₂O_ThreeSuch as oxide, or these₂A mixture of two or more species or a composite oxide is preferably used. The inorganic compound fine particles are preferably spherical or nearly spherical.
[0044]
Further, such non-conductive inorganic compound fine particles are preferably used in the form of a sol dispersed in water or an organic solvent, but the inorganic compound fine particles are monodispersed or nearly monodispersed in the coating solution. Inorganic compound fine particles in a state other than sol may be used as long as they can be dispersed.
Specifically, the conductive fine particles include the kind of matrix precursor contained in the coating liquid for coating formation, and the kind of inorganic compound fine particles as described above added to the coating liquid for coating formation as necessary. Although it varies depending on the amount and is not particularly limited, it is desirably contained in the range of 1 to 50% by weight, preferably 5 to 30% by weight, in terms of oxide, with respect to the total amount of the dry-solid component.
[0045]
When non-conductive inorganic compound particles are included in the coating solution, the total amount of conductive fine particles and inorganic compound particles may be in the range of 5 to 70% by weight in terms of oxide with respect to the total amount of the dry-solid component. preferable.
Moreover, it is preferable that the solid content density | concentration in the coating liquid for film formation exists in the range of 3 to 15 weight%. The concentration of the matrix precursor in the coating liquid for forming a film is desirably in the range of 1 to 14% by weight in terms of oxide.
[0046]
When a hydrolyzable compound such as alkoxysilane, metal alkoxide, or acetylacetonato chelate compound is used as the matrix precursor in the coating solution for coating formation, the moisture concentration of the coating solution for coating formation is 0. A range of 1 to 40% by weight is preferred.
The coating solution for film formation as described above is applied to the surface of the transparent electrode formed on the substrate by a method such as dipping method, spinner method, spray method, roll coater method, flexographic printing, and then formed on the surface of the transparent electrode. The transparent electrode protective film having the specific surface resistance is formed by a method of drying the coated film at room temperature to 90 ° C., and further curing by heating to 200 ° C. or higher, preferably 300 ° C. or higher.
[0047]
Further, the transparent electrode protective film formed on the surface of the transparent electrode is preferably subjected to curing acceleration treatment by the following method.
That is, after the coating step or the drying step, or during the drying step, the uncured film is irradiated with an electromagnetic wave having a wavelength shorter than that of visible light, or the uncured film is accelerated in the curing reaction. Expose to.
[0048]
Specific examples of the electromagnetic wave applied to the uncured coating film before heating include ultraviolet rays, electron beams, X-rays, and γ rays, but ultraviolet rays are preferable. For example, the emission intensity becomes maximum at about 250 nm and 360 nm, and the light intensity is 10 mW / cm.²Using the above high-pressure mercury lamp as an ultraviolet ray source, 100 mJ / cm²Or more, preferably 1000 mJ / cm²When the uncured film is irradiated with ultraviolet rays having the above energy amount, the curing reaction of the uncured film is accelerated.
[0049]
Examples of the gas that accelerates the curing reaction of the uncured film before heating include ammonia and ozone. Moreover, the hardening of the coating film in such a gas atmosphere is carried out in the above active gas atmosphere in which the gas concentration is 100 to 100,000 ppm, preferably 1000 to 10,000 ppm. Achieved by minute processing.
[0050]
When the curing acceleration treatment as described above is performed, polymerization of alkoxysilane, metal alkoxide, acetylacetonato chelate compound and the like used as a matrix precursor component in the coating is promoted, and at the same time, water remaining in the coating And the evaporation of the solvent is also promoted. For this reason, the heating and curing conditions such as the heating temperature and heating time required in the next heating step are alleviated, and the production of the coated substrate according to the present invention can be advantageously advanced.
[0051]
Moreover, even if this gas treatment is performed after heat curing, the same effect can be obtained.
[0052]
【The invention's effect】
In the liquid crystal display cell according to the present invention, the transparent electrode protective film containing conductive fine particles having a volume resistivity in a specific range is provided between the substrate with a transparent electrode and the alignment film, so that the upper and lower electrodes are electrically connected. In addition, static electricity generated when the alignment film is rubbed can be quickly removed through the transparent electrode protective film to prevent the alignment film from being charged.
[0053]
According to the method for manufacturing a liquid crystal display cell according to the present invention, a transparent electrode, a transparent electrode protective film containing conductive fine particles having a volume resistivity in a specific range, and an alignment film are sequentially laminated with good adhesion to each other. A liquid crystal display cell provided with a substrate with electrodes is obtained.
Therefore, according to the present invention, it is possible to prevent the alignment film from being damaged and the alignment failure of the liquid crystal in the liquid crystal display cell due to the charging of the alignment film.
[0054]
Furthermore, in the present invention, since the transparent electrode protective film contains conductive fine particles having an average particle diameter in a specific range and non-conductive inorganic compound particles having an average particle diameter in a specific range as necessary, the surface roughness is Fine and uniform. For this reason, the alignment film formed on the surface of the transparent electrode protective film is excellent in adhesiveness, and an alignment film having no damage enough to abnormally align the liquid crystal is obtained. Therefore, according to the present invention, a liquid crystal display cell with improved color unevenness of a display image is provided.
[0055]
Further, the liquid crystal display cell according to the present invention has a lower resistance of the transparent electrode protective film than that of the conventional insulating film, so that the impedance of the display circuit is lowered, and as a result, the driving voltage of the liquid crystal cell can be lowered.
[0056]
【Example】
EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to these Examples.
[0057]
[Example 1]
Silica sol A (silica fine particles with an average particle diameter of 5 nm in hexylene glycol₂60 g of silica sol containing 10% by weight of concentration), ethyl silicate 28 (ethyl silicate manufactured by Tama Chemical Industries, SiO₂(Concentration: 28% by weight) After mixing 21.4 g and stirring for 10 minutes, 185 g of hexylene glycol, 0.2 g of 61% nitric acid and 14 g of pure water were added, and Sb having an average particle diameter of 20 nm was added to hexylene glycol.₂O_Five・ NH₂120 g of conductive fine particle-dispersed sol containing 10% by weight of O fine particles in solid concentration was added and stirred for 3 hours to prepare Liquid B. Diisopropylpropoxy-dioctyloxytitanium in isopropyl alcohol solution (TiO₂Concentration: 10% by weight) 300 g, butanol solution of tributoxy-monoacetylacetonatozirconium (ZrO₂(Concentration: 13.5%) A mixture of 44.4 g and 255 g of hexylene glycol was added to liquid B and stirred for 48 hours to obtain a coating solution for forming a transparent electrode protective film having a solid content concentration of 6% by weight in terms of inorganic oxide. It was.
[0058]
On the glass substrate, a transparent electrode made of ITO is formed on a substrate with a transparent electrode (30Ω type manufactured by Asahi Glass Co., Ltd.) formed in a pattern so that a dot matrix cell can be formed. After applying by flexographic printing method and drying the obtained coating film at 100 ° C., it is 6,000 mJ / cm with a high pressure mercury lamp.²The transparent electrode protective film (1) was formed by irradiating the ultraviolet rays and then baking at 300 ° C. for 30 minutes. The film thickness of the obtained transparent electrode protective film (1) was measured with a stylus type step gauge Surfcom (manufactured by Tokyo Seimitsu Co., Ltd.).
[0059]
The results are shown in Table 2.
After forming an alignment film with a film thickness of about 50 nm on the transparent electrode protective film (1) with a polyimide resin, the obtained alignment film was rubbed under conditions of 25 ° C. and a relative humidity of about 30%.
In this way, a transparent electrode, a transparent electrode protective film (1), and an alignment film were sequentially laminated on the glass substrate, and a pair of substrates with a transparent electrode were obtained in which the alignment film was rubbed.
[0060]
The obtained pair of substrates with transparent electrodes are fixed with a sealing agent while being spaced apart via a plurality of spacer particles so that the transparent electrodes face each other, and after sealing the STN liquid crystal, the liquid crystal sealing port is UV cured. After sealing with resin, a liquid crystal display cell was prepared through a heating treatment at 120 ° C. for 1 hour.
Measurement of line marks
Static electricity is applied to the liquid crystal display cell using an electrostatic gun on the obtained liquid crystal display cell (the liquid crystal display cell is charged), and the disappearance of the linear trajectory (line trace) appearing along the transparent electrode wiring on the display screen. The degree was confirmed. This line mark causes static electricity to be introduced into some transparent electrode wirings, and the static electricity is charged to each dielectric layer of transparent electrode-insulating film-alignment film-liquid crystal layer and their interface. This is caused by abnormal orientation of the liquid crystal.
[0061]
The results are also shown in Table 2.
In addition, about the said line mark, the following evaluation was performed.
○ ... The mark disappears within 2 seconds
Δ: Marks disappear in 2 to 30 seconds
× ... The line mark disappears after 30 seconds
Observation of rubbing scratches
Further, a DC voltage was applied to the obtained liquid crystal display cell, and the presence or absence of scratches along the rubbing direction observed in the liquid crystal display cell was examined. This scratch becomes a standard for knowing the adhesion between the transparent electrode protective film and the alignment film. That is, if the adhesion between the transparent electrode protective film and the alignment film is poor, the alignment film may be damaged when the alignment film is rubbed. If there is a scratch on the alignment film, this scratch may be observed on the display screen during the operation of the liquid crystal display device, resulting in a display defect. This can be easily determined by visual observation by applying a DC voltage.
[0062]
Evaluation of vertical conductivity
For the evaluation of vertical conductivity, etc., first, in the process of making the above-described dot matrix type liquid crystal display cell, after spraying ordinary insulating spacer particles on a substrate having a transparent electrode protective film and an alignment film, the average is obtained. 5-10 particles / mm of elastic Au plating spacer particles (made by EW-P Catalyst Kasei Kogyo Co., Ltd.) larger than the particle size by 1.5 μm²After that, liquid crystal display cells were made by a normal process. When the entire display pixel portion was lit at a predetermined voltage, the degree of display failure due to a short circuit between the upper and lower transparent electrodes caused by the Au plating spacer particles mixed in the cell was confirmed.
[0063]

Measurement of half-life of surface resistance and withstand voltage
In addition, an alkali passivation film (SiO 2 that does not form a transparent electrode)₂The transparent electrode protective film (2) was formed on the glass substrate with sputter) by the film forming method described above, and the surface resistance of the base material was measured using a surface resistance meter Hiresta (manufactured by Mitsubishi Yuka Co., Ltd.). Moreover, the half life of the charged voltage of the same base material was measured using a charge attenuation device (electrostatic sweep memory KM-511, manufactured by Kasuga Electric Co., Ltd.).
[0064]
Refractive index measurement
Further, a transparent electrode protective film (3) was formed on the silicon wafer by the same film forming method, and the refractive index was measured using an ellipsometer.
The results are shown in Table 2.
[0065]
[Example 2]
Silica sol C (silica fine particles having an average particle size of 45 nm in hexylene glycol₂30 g of silica sol containing 10% by weight in concentration, ethyl silicate 28 (SiO 2₂96.4 g of γ-glycidoxypropyltrimethoxysilane (concentration: 28% by weight)₂(Concentration: 25.4 wt%) After mixing 70.9 g and stirring for 20 minutes, 664.5 g of hexylene glycol, 0.2 g of nitric acid with a concentration of 61 wt%, 18 g of pure water and hexylene glycol had an average particle size of 20 nm. Sb₂O_Five・ NH₂120 g of conductive fine particle dispersion sol containing 10% by weight of O fine particles in solid content concentration was added and stirred for 12 hours to obtain a coating solution for forming a transparent electrode protective film having a solid content concentration of 6% by weight in terms of inorganic oxide.
[0066]
On the electrode surface of the substrate with a transparent electrode (manufactured by Asahi Glass Co., Ltd .: 30Ω type) in which the transparent electrode made of ITO is formed in a pattern on the glass substrate using the obtained coating solution for forming a transparent electrode protective film. The transparent electrode protective film (1) was formed by applying by the flexographic printing method, drying the obtained coating film at 100 ° C., and baking at 200 ° C. for 30 minutes.
[0067]
Furthermore, using the substrate with a transparent protective film formed on the transparent electrode pattern under the above film forming conditions, a liquid crystal display cell was prepared in the same manner as in Example 1, and the state of the line marks and rubbing scratches caused by static electricity Evaluation was made on the conduction between the upper and lower electrodes.
Moreover, the transparent electrode protective films (2) and (3) were formed on the glass substrate with an alkali passivation film and the silicon wafer under the above film forming conditions.
[0068]
Example 1 shows the thickness of the transparent electrode protective film obtained (the thickness of the electrode protective film is the same for the protective films (1) to (3)), surface resistance, half-life of withstand voltage, and refractive index. It was measured by the same method.
The results are shown in Table 2.
[0069]
[Example 3]
Titania sol (titania fine particles with an average particle diameter of 20 nm in hexylene glycol₂30 g of titania sol containing 10% by weight), ethyl silicate 40 (SiO 2₂Concentration: 40% by weight) 30 g, IPA solution of titanium octylene glycolate (TiO₂(Concentration: 9% by weight) After mixing 400 g and stirring for 20 minutes, 435.8 g of hexylene glycol, 0.2 g of nitric acid having a concentration of 61% by weight, and 14 g of pure water were added, and the average particle size was further added to hexylene glycol. 20 nm Sb₂O_Five・ NH₂90 g of conductive fine particle-dispersed sol containing 10% by weight of O fine particles in solid content concentration was added and stirred for 12 hours to obtain a coating solution for forming a transparent electrode protective film having a solid content concentration of 6% by weight.
[0070]
The obtained coating solution for forming a transparent electrode protective film is applied on the electrode surface of a transparent electrode substrate (Asahi Glass Co., Ltd .: 30Ω type) on which a transparent electrode made of ITO is formed in a pattern on a glass substrate. After coating by the printing method and drying the obtained coating film at 100 ° C., it is 6,000 mJ / cm with a high-pressure mercury lamp.²The transparent electrode protective film (1) was formed by irradiating the ultraviolet rays and then baking at 300 ° C. for 30 minutes.
[0071]
Furthermore, using the substrate with a transparent protective film formed on the transparent electrode pattern under the above film forming conditions, a liquid crystal display cell was prepared in the same manner as in Example 1, and the state of the line marks and rubbing scratches caused by static electricity Evaluation was made on the conduction between the upper and lower electrodes.
Moreover, the transparent electrode protective films (2) and (3) were formed on the glass substrate with an alkali passivation film and the silicon wafer under the above film forming conditions.
[0072]
Example 1 shows the thickness of the transparent electrode protective film obtained (the thickness of the electrode protective film is the same for the protective films (1) to (3)), surface resistance, half-life of withstand voltage, and refractive index. It was measured by the same method.
The results are shown in Table 2.
[0073]
[Reference example4]
  Ethyl silicate 28 (SiO₂(Concentration: 28% by weight) To 150 g, 40 g of butyl cellosolve, 304.4 g of hexylene glycol, 0.4 g of nitric acid having a concentration of 61% by weight and 15 g of pure water were added, and Sb having an average particle diameter of 20 nm was added to hexylene glycol.₂O5 ・ nH₂90 g of conductive fine particle-dispersed sol containing 10% by weight of O fine particles in solid content concentration was added and stirred for 3 hours to prepare Liquid D. Diisopropylpropoxy-dioctyloxytitanium in isopropyl alcohol solution (TiO₂Concentration: 10% by weight) 60 g, butanol solution of tributoxy-monoacetylacetonatozirconium (ZrO₂(Concentration: 13.5% by weight) A mixture of 22.2 g and 318 g of hexylene glycol was added to liquid D and stirred for 48 hours, and a coating solution for forming a transparent electrode protective film having a solid content concentration of 6% by weight in terms of inorganic oxide was obtained. Obtained.
[0074]
The obtained coating solution for forming a transparent electrode protective film is formed on a glass substrate with a flexo electrode on the electrode surface of a substrate with a transparent electrode (Asahi Glass Co., Ltd .: 30Ω type) on which a transparent electrode made of ITO is formed in a pattern. After coating by the printing method and drying the obtained coating film at 100 ° C., it is 6,000 mJ / cm with a high-pressure mercury lamp.²The transparent electrode protective film (1) was formed by irradiating the ultraviolet rays and then baking at 300 ° C. for 30 minutes.
[0075]
Furthermore, using the substrate with a transparent protective film formed on the transparent electrode pattern under the above film forming conditions, a liquid crystal display cell was prepared in the same manner as in Example 1, and the state of the line marks and rubbing scratches caused by static electricity Evaluation was made on the conduction between the upper and lower electrodes.
Moreover, the transparent electrode protective films (2) and (3) were formed on the glass substrate with an alkali passivation film and the silicon wafer under the above film forming conditions.
[0076]
Example 1 shows the thickness of the transparent electrode protective film obtained (the thickness of the electrode protective film is the same for the protective films (1) to (3)), surface resistance, half-life of withstand voltage, and refractive index. It was measured by the same method.
The results are shown in Table 2.
[0077]
[referenceExample 5]
  Ethyl silicate 28 (SiO₂Concentration: 28% by weight) and 107.1 g, γ-glycidoxypropyltrimethoxysilane (SiO₂(Concentration: 25.4% by weight) was mixed with 70.9 g, hexylene glycol (676.8 g), 61% nitric acid (0.2 g) and pure water (25 g) were added, followed by stirring for 3 hours to prepare solution E. Sb prepared in advance using silicic acid solution and potassium antimonate as raw materials₂O_Five-SiO₂120 g of composite type sol (average particle size 15 nm, solid content concentration 10% by weight, conductive fine particle dispersion sol containing hexylene glycol) is added to E solution and stirred for 12 hours, and the solid content concentration 6% by weight in terms of inorganic oxide A coating solution for forming a transparent electrode protective film was obtained.
[0078]
On the electrode surface of the substrate with a transparent electrode (manufactured by Asahi Glass Co., Ltd .: 30Ω type) in which the transparent electrode made of ITO is formed in a pattern on the glass substrate using the obtained coating solution for forming a transparent electrode protective film. The transparent electrode protective film (1) was formed by applying by the flexographic printing method, drying the obtained coating film at 100 ° C., and baking at 200 ° C. for 30 minutes.
[0079]
Furthermore, using the substrate with a transparent protective film formed on the transparent electrode pattern under the above film forming conditions, a liquid crystal display cell was prepared in the same manner as in Example 1, and the state of the line marks and rubbing scratches caused by static electricity Evaluation was made on the conduction between the upper and lower electrodes.
Moreover, the transparent electrode protective films (2) and (3) were formed on the glass substrate with an alkali passivation film and the silicon wafer under the above film forming conditions.
[0080]
Example 1 shows the thickness of the transparent electrode protective film obtained (the thickness of the electrode protective film is the same for the protective films (1) to (3)), surface resistance, half-life of withstand voltage, and refractive index. It was measured by the same method.
The results are shown in Table 2.
[0081]
[Comparative Example 1]
Ethyl silicate 28 (SiO₂(Concentration: 28 wt%) 85.7 g, dipropylene glycol 100 g, hexylene glycol 202 g, nitric acid 0.2 g of 61 wt% concentration and pure water 12 g were mixed and stirred for 3 hours to prepare Liquid F. Tetranormal butyl titanate (TiO₂Concentration: 23.5 wt%) 127.7 g, zirconium normal propoxide (ZrO₂(Concentration: 28%) A mixture of 21.4 g and 451 g of hexylene glycol was added to the liquid F and stirred for 48 hours to obtain a coating solution for forming a transparent electrode protective film having a solid content concentration of 6% by weight in terms of inorganic oxide.
[0082]
The obtained coating solution for forming a transparent electrode protective film is applied on the electrode surface of a transparent electrode substrate (Asahi Glass Co., Ltd .: 30Ω type) on which a transparent electrode made of ITO is formed in a pattern on a glass substrate. After coating by the printing method and drying the obtained coating film at 100 ° C., it is 6,000 mJ / cm with a high-pressure mercury lamp.²Was then irradiated at 300 ° C. for 30 minutes to form a transparent electrode protective film.
[0083]
Furthermore, using the substrate with a transparent protective film formed on the transparent electrode pattern under the above film forming conditions, a liquid crystal display cell was prepared in the same manner as in Example 1, and the state of the line marks and rubbing scratches caused by static electricity Evaluation was made on the conduction between the upper and lower electrodes.
Moreover, the transparent electrode protective films (2) and (3) were formed on the glass substrate with an alkali passivation film and the silicon wafer under the above film forming conditions.
[0084]
Example 1 shows the thickness of the transparent electrode protective film obtained (the thickness of the electrode protective film is the same for the protective films (1) to (3)), surface resistance, half-life of withstand voltage, and refractive index. It was measured by the same method.
The results are shown in Table 2.
[0085]
[Comparative Example 2]
Ethyl silicate 28 (SiO₂(Concentration: 28% by weight) After mixing 85.7 g, 374 g hexylene glycol, 0.3 g 61% nitric acid and 20 g pure water, the mixture was stirred for 1 hour to solidify tin oxide fine particles having an average particle diameter of 10 nm in hexylene glycol. 120 g of conductive fine particle-dispersed sol containing 10% by weight dispersed in a partial concentration was added and stirred for 12 hours to prepare Liquid G. Diisopropylpropoxy-dioctyloxytitanium in isopropyl alcohol solution (TiO₂(Concentration: 10% by weight) A mixture of 240 g and 160 g of hexylene glycol was added to the liquid F and stirred for 48 hours to obtain a coating solution for forming a transparent electrode protective film having a solid content concentration of 6% by weight in terms of inorganic oxide.
[0086]
The obtained coating solution for forming a transparent electrode protective film is applied on the electrode surface of a transparent electrode substrate (Asahi Glass Co., Ltd .: 30Ω type) on which a transparent electrode made of ITO is formed in a pattern on a glass substrate. After coating by the printing method and drying the obtained coating film at 100 ° C., it is 6,000 mJ / cm with a high-pressure mercury lamp.²The transparent electrode protective film (1) was formed by irradiating the ultraviolet rays and then baking at 300 ° C. for 30 minutes.
[0087]
Furthermore, using the substrate with a transparent protective film formed on the transparent electrode pattern under the above film forming conditions, a liquid crystal display cell was prepared in the same manner as in Example 1, and the state of the line marks and rubbing scratches caused by static electricity Evaluation was made on the conduction between the upper and lower electrodes.
Moreover, the transparent electrode protective films (2) and (3) were formed on the glass substrate with an alkali passivation film and the silicon wafer under the above film forming conditions.
[0088]
Example 1 shows the thickness of the transparent electrode protective film obtained (the thickness of the electrode protective film is the same for the protective films (1) to (3)), surface resistance, half-life of withstand voltage, and refractive index. It was measured by the same method.
The results are shown in Table 2.
[0089]
[Comparative Example 3]
Silica sol A (silica fine particles with an average particle diameter of 5 nm in hexylene glycol₂60 g of silica sol containing 10% by weight of concentration), ethyl silicate ethyl silicate 28 (SiO₂Concentration: 28% by weight) 85.7 g, methyltrimethoxysilane (SiO₂(Concentration: 44 wt%) 40.9 g of a mixed solution is doped with 673.1 g of hexylene glycol, 0.3 g of nitric acid with a concentration of 61 wt%, 20 g of pure water, and antimony with an average particle diameter of 10 nm in hexylene glycol. 120 g of conductive fine particle-dispersed sol containing 10% by weight of tin oxide fine particles dispersed in a solid content concentration and stirred for 12 hours, and a coating solution for forming a transparent electrode protective film having a solid content concentration of 6% by weight in terms of inorganic oxide Got.
[0090]
Using the obtained coating solution for forming a transparent electrode protective film, on the electrode surface of a substrate with a transparent electrode (manufactured by Asahi Glass Co., Ltd .: 30Ω type) in which a transparent electrode made of ITO is formed in a pattern on a glass substrate. The transparent electrode protective film (1) was formed by applying by the flexographic printing method, drying the obtained coating film at 100 ° C., and baking at 200 ° C. for 30 minutes.
[0091]
Furthermore, using the substrate with a transparent protective film formed on the transparent electrode pattern under the above film forming conditions, a liquid crystal display cell was prepared in the same manner as in Example 1, and the state of the line marks and rubbing scratches caused by static electricity Evaluation was made on the conduction between the upper and lower electrodes.
Moreover, the transparent electrode protective films (2) and (3) were formed on the glass substrate with an alkali passivation film and the silicon wafer under the above film forming conditions.
[0092]
Example 1 shows the thickness of the transparent electrode protective film obtained (the thickness of the electrode protective film is the same for the protective films (1) to (3)), surface resistance, half-life of withstand voltage, and refractive index. It was measured by the same method.
The results are shown in Table 2.
[0093]
[Comparative Example 4]
Silica sol H (silica fine particles having an average particle diameter of 25 nm in hexylene glycol₂120 g of silica sol containing 10% by weight in concentration, ethyl silicate 28 (SiO 2₂Concentration: 28 wt%) 64.3 g, γ-glycidoxypropyltrimethoxysilane (SiO₂(Concentration: 25.4 wt%) To a mixture of 118.1 g, 682.4 g of hexylene glycol, 0.2 g of nitric acid having a concentration of 61 wt% and 15 g of pure water were added and stirred for 12 hours, and then the solid content concentration was 6 wt%. A coating solution for forming a transparent electrode protective film was obtained.
[0094]
Using the obtained coating solution for forming a transparent electrode protective film, on the electrode surface of a substrate with a transparent electrode (manufactured by Asahi Glass Co., Ltd .: 30Ω type) in which a transparent electrode made of ITO is formed in a pattern on a glass substrate. The transparent electrode protective film (1) was formed by applying by the flexographic printing method, drying the obtained coating film at 100 ° C., and baking at 200 ° C. for 30 minutes.
[0095]
Furthermore, using the substrate with a transparent protective film formed on the transparent electrode pattern under the above film forming conditions, a liquid crystal display cell was prepared in the same manner as in Example 1, and the state of the line marks and rubbing scratches caused by static electricity Evaluation was made on the conduction between the upper and lower electrodes.
Moreover, the transparent electrode protective films (2) and (3) were formed on the glass substrate with an alkali passivation film and the silicon wafer under the above film forming conditions.
[0096]
Example 1 shows the thickness of the transparent electrode protective film obtained (the thickness of the electrode protective film is the same for the protective films (1) to (3)), surface resistance, half-life of withstand voltage, and refractive index. It was measured by the same method.
[0097]
[Table 2]

[Brief description of the drawings]
FIG. 1 is a cross-sectional view schematically showing a liquid crystal display cell according to the present invention.
FIG. 2 is a schematic diagram showing a distribution state of conductive fine particles having poor monodispersibility in a protective film.
[Explanation of symbols]
1 ... Liquid crystal display cell
2, 2 '... Substrate with transparent electrode
3. Spacer particles
4 ... Liquid crystal
21 ... Transparent substrate
22 ... Transparent electrode film
23 ... Transparent electrode protective film
24 ... Alignment film
d ... Interval

Claims (2)

In a liquid crystal display cell comprising a substrate with a transparent electrode in which a transparent electrode, a transparent electrode protective film and an alignment film are sequentially laminated on the substrate,
The transparent electrode protective film has a thickness of 20 to 150 nm , a volume resistivity of 10 ³ to 10 ¹² Ω · cm, and antimonic acid (S b ₂ O ₅ · nH ₂ O: n 0.02 to 4) consists of,
1 to 50% by weight of conductive fine particles having an average particle size of 1 to 50 nm ,
And non-conductive inorganic compound particles having an average particle diameter of 2 to 200 nm may be conductive fine particles, oxides such as SiO ₂ , TiO ₂ , ZrO ₂ , Al ₂ O ₃ , or a mixture of two or more thereof.
Is a liquid crystal comprising non-conductive inorganic compound particles made of a composite oxide in a total amount of conductive fine particles and non-conductive inorganic compound particles in an amount of 5 to 70% by weight in terms of oxide. Display cell. When manufacturing a liquid crystal display cell including a substrate with a transparent electrode in which a transparent electrode, a transparent electrode protective film, and an alignment film are sequentially laminated on the substrate, the volume resistivity is applied to the surface of the transparent electrode formed on the substrate. 10 ³ to 10 ¹² Ω · cm , antimonic acid (S b ₂ O ₅ · nH ₂ O: n is
0.1 to 50 weight conductive particles consisting of 02-4) in terms of oxide relative to the total amount of dryness components
%, SiO ₂ , TiO ₂ , ZrO ₂ , Al ₂ O _3, etc., or a mixture or composite oxide of two or more thereof, and non-conductive inorganic compound particles having an average particle size of 2 to 200 nm The total amount of the conductive fine particles and the non-conductive inorganic compound particles is 5 to 70% by weight in terms of oxide, and the matrix precursor is 1 to 14% by weight in terms of oxide with respect to the total amount of the dry-solid component . The manufacturing method of the liquid crystal display cell characterized by including the process of apply | coating the coating liquid for film formation contained by quantity, and hardening the obtained coating film and forming a transparent electrode protective film.

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