JP3953588B2 - Color filter and liquid crystal display device using the same - Google Patents

Description

図８は、ダイナミック硬さ値を求める荷重試験を説明する図である。まず、図８（Ａ）のように設定荷重５．０ｍＮまでの負荷を上記負荷速度で、先端が三角錐状の三角錐圧子（図８（Ｃ））で着色層に与え、５．０ｍＮに到達後、５秒間の間荷重を保持した後、その時の荷重（５．０ｍＮ）と圧子の押し込み深さからダイナミック硬さ値を求めた（図８（Ｂ））。
【００３２】
その結果は、表１に示すとおりであり、アクリル系＜ポリビニルアルコール系＜ポリイミド系 の傾向が認められた。なお、表１中の測定単位は、ダイナミック硬さに対する値を示す。
【表 １】

【００３３】
試作１によるカラーフィルタの柱状体部分のダイナミック硬さを、上記と同一の方法で測定した。その結果は、表２に示すとおりであり、この場合にも着色層と同様にアクリル系＜ポリビニルアルコール系＜ポリイミド系 の傾向が認められた。なお、表２中の測定単位は、ダイナミック硬さに対する値を示す。
このことより、柱状体の硬さは、着色層に使用する樹脂材料によって左右されることが確認された。アクリル系に比べポリビニルアルコール系は、柱状体の強度が１．１３倍、ポリイミド系は１．２７倍の強度が得られる。
これはギャップ制御機能を有する柱状体をカラーフィルタに形成した場合、アクリル系が柱状体を一定面積に対して、１００個設ける必要があるのに対して、ポリビニルアルコール系では８８個、ポリイミド系では７８個の個数でよいことを意味する。なお、表２中、「Ｒ上」とは、赤の着色層上に形成された柱状体を意味する。
【００３４】
【表 ２】

【００３５】
〔試作２〕
試作２によるカラーフィルタの柱状体部分の強度を、超微小硬度計を使用して、以下の方法で測定した。
＜測定方法＞

【００３６】
図９は、塑性変形量、弾性変形量を求める荷重試験を説明する図である。図９（Ａ）は試験時における時間経過とその時の荷重を表しており、まず円柱状圧子を用いて一定の負荷速度で柱状体部分に設定荷重の５．０ｍＮに到達するまで負荷を与える。次に、５秒間設定荷重を保持する。さらに、一定の除荷速度（負荷速度と同じ）で除荷を行い無負荷の状態に戻す。これにより一回の測定が終了する。実際には図９（Ｂ）に示すように、負荷時には設定荷重までは押し込み深さがＤ１まで増し、除荷時には押し込み深さがＤ２まで戻る。Ｄ２は除荷後にも変形した量であるので、塑性変形量を表し、Ｄ１は設定荷重での総変形量を表す。従って、Ｄ１からＤ２を差し引けば、設定荷重での弾性変形量を算出できる。
【００３７】
表３は、Ｒ，Ｇ，Ｂの着色層上に形成した柱状体の柱サイズとその柱状体に測定条件の５ｍＮの荷重をかけた場合の測定結果を示したものである。
【００３８】
【表 ３】

なお、柱サイズ，Ｄ１，Ｄ２，弾性変形，塑性変形の単位は、μｍ
柱面積は、μｍ² 荷重は、ｍＮ である。
以下の表において同じである。
【００３９】
その結果、表３のように、着色層Ｒ上に形成された柱状体に注目すると、柱面積を大きくしていくと、総変形量（Ｄ１）が１００μｍ² と２００μｍ² を境として変化していくことがわかる。この変化は塑性変形量（Ｄ２）でも同様の変化を示しており、柱状体の柱面積が２００μｍ² 以上であれば、塑性変形量が０．０５μｍ以下となる。次に、柱面積２００μｍ² に注目して各着色層の塑性変形量をみると０．０４μｍ前後であり、ほぼ同様の値を示していることがわかる。柱状体の構成は、図４（Ｂ）に示すように各層で異なっている。すなわち、Ｒ層上に形成したものは、そのほかの着色層上に形成された柱状体に比べ着色層により柱の側面等がカバーされてはおらず、柱状体の２層構造に直接負荷がかかることとなる。従って、７５μｍ² での塑性変形量は、そのほかの層上に形成されたものに比べＲ層上に形成された柱状体の方が悪い。しかしながら上述のように２００μｍ² 以上で形成されたものは柱状体の構成の違いにかかわらず、ほぼ同様の値を示している。
【００４０】
このことから、２００μｍ² 以上の柱面積を有することで、塑性変形量を０．０５μｍ以下におさえることが説明できる。すなわち、柱状体の底面断面積が、２００μｍ² 以上であれば、塑性変形量は柱状体の構成の影響を受けずに、０．０５μｍ以下におさえることができる。
面積２００μｍ² の柱状体を正方形に形成する場合には、一辺が、１４μｍ程度となるが、２００μｍ² 以上であれば無制限という意味ではない。大きければ画質を低下させるし、明視の距離で柱状体が認識されないことが望ましいので、できるかぎり小さいことにこしたことはない。通常、人間の目の分解能（点の存在を検知できる最小の大きさ）が、角度にして約１分であり、これをもとに計算すると、約３０ｃｍの距離から液晶ディスプレイをみた際の最小分解能が８７μｍ程度となる。従って、対角線が８７μｍの正方形とした場合は、その面積は約７５７０μｍ² となる。
【００４１】
【表 ４】

【００４２】
試作２のうち、Ｒ層においてＩＴＯ層を設けたものの測定値を表４に示す。ＩＴＯ層を設けない表３の試作２と同様、総変形量（Ｄ１）が１００μｍ² と２００μｍ² を境として変化していることがわかる。また表３と比較して弾性変形量はほぼ同一の値を示しているのに対し、塑性変形量は柱サイズの依存性はみられず、０．１μｍ前後の値を示している。
これらのことから、弾性変形量は下地の着色柱状体に依存し、塑性変形量は無機膜であるＩＴＯ層に依存することがわかる。この場合には、５ｍＮの荷重に対して０．１２μｍ以下に変形量を想定して柱状体を設計すれば、柱サイズの依存性はなく柱状体を配置できる。また、あとから述べるように、ＩＴＯ膜破壊荷重は遙かに大きく、ＩＴＯの破壊による液晶表示装置での実際上の支障は生じないものと考えられる。
【００４３】
〔試作３〕
試作３による試作カラーフィルタの柱状体部分の強度を、試作２と同様の方法で超微小硬度計を使用して測定した。その結果を表５に示す。なお、この測定はＩＴＯ層を設ける前の状態（図６（Ｂ））で行ったものである。
【００４４】
【表 ５】

【００４５】
表５からも柱面積を大きくしていくと、総変形量（Ｄ１）が１００μｍ² と２００μｍ² を境として変化していくことがわかる。この変化は塑性変形量（Ｄ２）でも同様の変化を示しており、柱状体の柱面積が、２００μｍ² 以上であれば、透明な感光性材料による柱状体であっても塑性変形量が０．０５μｍ以下となる。
試作３のうち、ＩＴＯ層を設けたものの測定値を表６に示す。
【００４６】
【表 ６】

【００４７】
ＩＴＯ層を設けない表５の試作３と同様、総変形量（Ｄ１）が１００μｍ² と２００² μｍを境として変化していることがわかる。また表５と比較して弾性変形量はほぼ同一の値を示しているのに対し、塑性変形量は柱サイズの依存性はみられず、０．１μｍ前後の値を示している。これらのことから、試作２と同様、弾性変形量は下地の透明柱状体に依存し、塑性変形量は無機膜であるＩＴＯ層に依存することがわかる。この場合には、５ｍＮの荷重に対して０．１２μｍ以下に変形量を想定して柱状体を設計すれば、柱サイズの依存性なく柱状体を配置できる。
【００４８】
〔試作４〕
次に、試作４による試作カラーフィルタの柱状体部分の荷重試験を、以下の方法で実施した。この場合の柱状体４の断面積は、前記のように１５×２５μｍである。パラメータとして荷重を変化させ、弾性変形量および塑性変形量を測定した。
＜測定方法＞

【００４９】
図１０は、柱状体の荷重に対する変形量を示すグラフと測定数値である。
図１０（Ａ）は、試作４のカラーフィルタの柱状体部分を測定した結果をグラフ化したものであり、図１０（Ｂ）は、その測定数値を示す表である。
グラフより明らかなように、１００ｍＮ以上の荷重がかかった場合には、弾性変形と塑性変形の傾きが同じとなる。このことから、柱状体が破壊されていくことがわかる。すなわち、１５×２５μｍの柱状体では、柱１個で１００ｍＮ（１０．２ｇｆ）の耐荷重に耐えられ、実用上充分な値であることがわかる。
ところで、この柱状体がいかに実用的といっても限界は存在する。図１０のグラフから明らかなように、１００ｍＮ以上の荷重をかけた場合には変形量が急激に変化する。作業時にたとえば柱状体の高さが４μｍあったとしても、２００ｍＮの荷重をかけた場合には、０．５μｍの塑性変形となり、ギャップ制御は３．５μｍになってしまう。着色層を重ねあわせて柱の高さを高くさせるためには、一般的には着色層を厚くする必要があり、設計およびプロセスが非常に困難になる。一方、１００ｍＮ以下の荷重では、０．２μｍ以下の塑性変形であり、最初からその変形量を見込んで柱状体の設計が可能になる。
【００５０】
もちろん着色層を形成後、透明樹脂をパターニングして柱状体を形成する場合には、上述のような荷重に対する組成変形量を加味して最終的に必要な柱状体の高さを設計すればよい。
また、後述のように表８から荷重５ｍＮに対するミクロパール１個の塑性変形量は０．５μｍであるのに対し、柱状体では上述のように２００ｍＮの荷重である。つまり、約４０倍の荷重に耐え得ると言える。このことからも実用上充分な値であることがわかる。
【００５１】
〔試作５〕
次に、試作５によるカラーフィルタの柱状体部分のＩＴＯ破壊負荷試験を、以下の方法で実施した。この場合の柱状体の断面積は、１０×１０、１５×１５、２０×２０、２５×２５μｍの４種類である。これらの柱状体に対して荷重を変化させ、その後の基板を顕微鏡で観察し、ＩＴＯの破壊の有無を確認し破壊される以上の荷重を負荷させた。
＜測定方法＞

【００５２】
図１１は、柱状体部分のＩＴＯ破壊負荷試験の結果を示す図である。上記試験荷重での総変形量をプロットしたものが図１１であり、図のように、１０×１０μｍでは２００ｍＮ、１５×１５μｍでは３５０ｍＮ、２０×２０μｍでは５００ｍＮ、２５×２５μｍでは７５０ｍＮでＩＴＯが破壊されることが確認できた。また、グラフから明らかなように、ＩＴＯ破壊時に変曲点が存在することが確認できる。また、柱サイズにより破壊変曲点が異なることがわかる。いずれのサイズでもＩＴＯの破壊荷重は通常、柱状体にかかる荷重に比べれば遙かに高く、この柱状体がギャップ制御材料として充分に機能を果すことが確認された。
【００５３】
（比較例）
次に、通常のカラーフィルタに球状のスペーサを使用した場合のスペーサの塑性変形量を測定した。すなわち、試作１と同様にして形成された柱状体のないカラーフィルタ基板に、平均粒子径５．００±０．０５μｍ、標準偏差０．１９±０．０１μｍのスペーサ（積水ファインケミカル株式会社製「ミクロパールＳＰＮ−２０５」）を散布したものについて、試作２と同一の測定方法で測定した。その試験方法は下記のとおりである。なお上記スペーサについては以下、「ミクロパール」と呼ぶ。
【００５４】
（ミクロパールの試験方法）
ＩＰＡ（イソプロピルアルコール 純正化学株式会社製）にミクロパールを少量添加し、充分に攪拌させて分散液を作製する。ミクロパールが分散したＩＰＡ溶液に布片をピンセットを用いて浸漬させる。上記布片をカラーフィルタにこすりつけ、ミクロパールを付着させる。その後、室温でＩＰＡを乾燥させる。
顕微鏡により着色画素１個について、ミクロパールが１個付着したものを確認し、測定対象とした。ただし表１０については比較のため、ミクロパール１個のものと２個のものを測定した。
【００５５】
その結果は、表７〜表１０に示すとおりであるが、表７、表８に示すように、ミクロパールの荷重５ｍＮに対する塑性変形量は０．５から０．６μｍ程度であり、本発明の柱状体に比べて一桁程度、塑性変形量が大きいことがわかる。
【００５６】
【表 ７】

【００５７】
【表 ８】

【００５８】
【表 ９】

【００５９】
【表１０】

【００６０】
次に、表８と表９を比較すると、表８の標準的なカラーフィルタ＋ＩＴＯ＋ミクロパールの塑性変形量が、０．５１μｍ程度であるのに対し、ガラス上にミクロパールを付着させたサンプル（表９）では、その塑性変形量が０．４２μｍ程度である。その差はカラーフィルタ自身に寄与する変形量であって、０．１μｍ以下であり、そのほとんどの変形がミクロパールの変形であると推定できる。表９のように荷重を変化させたとき、総変形量、塑性変形量ともに変化することより、ミクロパールが変形することがわかる。
ミクロパールの個数が塑性変形量に影響することを確認するために、１画素に２個のミクロパールが存在するものについて測定を行った。結果は表１０に示すとおりである。塑性変形量を少なくするためには、１画素に複数個のミクロパールを散布する必要がある。
【００６１】
ここで、１個当たりのスペーサーにどの程度の荷重がかかるかを求めてみる。今、１１．３インチ（画面の対角線長さ）のパネルに１０ｋｇｆの荷重が全体にかかることを想定する。１１．３インチのパネルの場合、両辺は通常１７２．８×２３０．４ｍｍであり、その面積は、約４０，０００ｍｍ² （４００ｃｍ² ）になる。スペーサーは通常１ｍｍ² に１００〜２００個散布されるため全体では、４００万個〜８００万個の数が散布されることになる。この数で、１０ｋｇｆを除すれば、１個のスペーサーにかかる荷重は、１．２５ｍｇｆ〜２．５０ｍｇｆとなる。
【００６２】
もう少し具体的な数値で算出すると基板張り合わせ時にかかる圧力は０．４５〜０．５５ｋｇ／ｃｍ² と言われている。今、基板張り合わせ時にかかる圧力を０．５ｋｇ／ｃｍ² とすると、基板全体にかかる力は２００ｋｇｆである。この数で上記１個のスペーサにかかる荷重を求めれば、２５〜５０ｍｇｆとなる。
【００６３】
ここで、試験荷重５．０ｍＮ（０．５１ｇｆ）はスペーサ１０〜２０個にかかる荷重に相当する。これは上述から０．１ｍｍ² に存在するスペーサ量に相当し、Ｓ−ＶＧＡ（スーパー ビデオ グラフィックス アレイ）の１画素のサイズは、２８８μｍ×９６μｍであることを考えると３．６画素分に相当する。
すなわち、試験荷重５．０ｍＮ（０．５１ｇｆ）は現状使われているパネルのインチサイズ、ディスプレイ規格から考えても通常スペーサでのＲＧＢの３画素分程度に相当する。
【００６４】
上記のように、アクリル系の着色材料では柱状体を形成したカラーフィルタの試作２、試作３がミクロパール以上の塑性変形に対する能力を有し、ギャップ制御材料として充分に有効であることが確認された。
一方、アクリル系、ポリビニルアルコール系、ポリイミド系着色材料では柱状体を形成した試作１のカラーフィルタでは、アクリル系の着色材料による柱状体が硬度的にはポリビニルアルコール系、ポリイミド系より低い値であることが確認できた。このことからも、アクリル系のものがギャップ制御材料として充分に有効であれば、他の２種の材料も充分にその機能を発揮し得るものと考えられる。
【００６５】
（液晶表示装置に関する実施例）
上記、試作結果より、アクリル感材による１５×１５μｍの底面断面積の柱状体を着色層上に有し、さらにカラーフィルタ基板の周囲のシール材塗布部にも、５０×５０μｍの柱状体を設けた液晶用カラーフィルタ（試作１による着色感材による柱状体のものと試作３による透明感材による柱状体のものの２種）を作製し、それぞれを用いて、液晶表示装置を組み立てた。
まず、上記試作方法により作製されたＴＦＴ基板上にポリイミド系の配向膜を塗布し配向処理を施し対向基板を形成した。カラーフィルタ側にも同様にポリイミド系の配向膜を塗布し、配向処理を施した後、カラーフィルタ基板側の外周にシール材（三井東圧化学株式会社製「ストラクトボンドＸＮ−２１−Ｓ−Ｂ」）を塗布し、対向基板とカラーフィルタ基板とを張り合わせ、液晶注入部を残して封着した。
最後に上記のセル基板に液晶を充填して封止し、所定の駆動回路、照明装置を設けることにより液晶表示装置が完成した。
完成した液晶表示装置は、いずれも対向基板とカラーフィルタ間が一定間隔に保たれ、画像表示機能試験でも良好な結果が得られた。
【００６６】
【発明の効果】
本発明では、以下のような顕著な効果を有する。
▲１▼スペーサの代替部となる柱状体の材質・サイズ・強度を選定することで従来のスペーサと同様な機能を充分に持たせることができる。
▲２▼着色感材による柱状体の場合はマスクパターンを変更することで、あらたに工程を付加させず均一な間隔を有する柱状体を形成できる。透明感材による柱状体の場合は、任意の高さの柱状体を精度よく形成することができる。
▲３▼いずれの場合も一定の規則的関係で柱状体が形成され、固定されているので、スペーサーのように移動を起こし画像表示を損なうことがなく、かつ、光散乱の心配がない。
▲４▼カラーフィルタ基板周囲のシール部に柱状体を設けることにより、シール材にスペーサ材料を含ませる必要がなくなる。
【図面の簡単な説明】
【図１】 本発明の液晶用カラーフィルタの一例を示す概略構成図である。
【図２】 本発明の液晶用カラーフィルタの一実施形態の第１の工程を示す図である。
【図３】 第２の工程を示す図である。
【図４】 第３の工程を示す図である。
【図５】 本発明の液晶用カラーフィルタの他の実施形態の第１の工程を示す図である。
【図６】 第２の工程を示す図である。
【図７】 第３の工程を示す図である。
【図８】 ダイナミック硬さ値を求める荷重試験を説明する図である。
【図９】 塑性変形量、弾性変形量を求める荷重試験を説明する図である。
【図１０】 柱状体の荷重に対する変形量を示すグラフと測定数値である。
【図１１】 柱状体部分のＩＴＯ破壊負荷試験の結果を示す図である。
【符号の説明】
１ 液晶用カラーフィルタ
２ 透明基板
３ 着色層またはカラーフィルタ層
４ 柱状体
５ 透明導電膜層
６ オーバーコート層[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a liquid crystal display device typified by a personal computer, and in particular, a color filter of the liquid crystal display device has a large number of minute columnar bodies that perform a gap control function with respect to a counter substrate, and the columnar body is a specific material. The present invention relates to a color filter that is optimized in shape and strength, and a liquid crystal display device using the color filter.
[0002]
[Prior art]
In the conventional liquid crystal display device, in order to maintain the distance between the two substrates facing each other, a spacer is provided between them to keep the thickness of the liquid crystal layer uniform in the plane. Yes. For this spacer, spherical particles of plastic or silica are usually used as gap control powder. As the spacer, one having a diameter of 1.5 to 8.0 μm is used according to the use and the thickness of the liquid crystal. In addition, the spacer is used by spraying on one substrate and sealing the outer peripheral portion with a sealing material.
However, since it is performed in the spraying process as described above, the position where it is installed is not specified, and a situation occurs in which it is located in the display pixel portion or several pieces gather and aggregate. In addition, the spacer may move during application of voltage or during cell conveyance to damage the alignment film.
For this reason, a color filter with a gap function has been proposed in which a three-layer structure formed by overlapping three colored layers of a color filter is used as a spacer substitute for the purpose of specifying the installation position and preventing the movement of the spacer ( JP-A-5-196946).
However, although the publication discloses that a three-layer structure is formed in the black matrix portion, it does not disclose that the spacer functions sufficiently. That is, in order to form a three-layer structure on a black matrix by miniaturizing the black matrix accompanying the increase in the aperture ratio, it is necessary to reduce the size of the three-layer structure. Further, even if it is not formed on the black matrix, the number thereof needs to be as small as possible in order not to affect the pixel display. That is, it is important that the three-layer structure is minute and has a small amount and strong strength.
[0003]
[Problems to be solved by the invention]
The present invention solves the above-mentioned problems, and the object of the present invention is to sufficiently define the material, size, and strength of the columnar body as an alternative part of the spacer without affecting the display. An object of the present invention is to provide a color filter and a liquid crystal display device which are minute and have an alternative portion of a spacer with a small number of columns.
[0004]
[Means for Solving the Problems]
To solve the above problems, embodiments of the liquid crystal color filter of the present invention has a number of columnar body performing gap control function between the color filter and the opposite substrate to the colored layer, and, the columnar body photolithography a color filter formed by, the columnar body is a polyimide resin, polyvinyl alcohol resin state, and are not formed by material mainly to either acrylic resin, the columnar bodies on the columnar body A liquid crystal color having a transparent conductive film, a plastic deformation amount of 0.12 μm or less with respect to a load of 5 mN of a single columnar body, and a bottom cross-sectional area of the single columnar body of less than 200 μm ² In the filter.
Since such a color filter for liquid crystal is used, the gap can be accurately controlled and the strength of the columnar body can be sufficiently increased.
[0005]
[0006]
[0007]
[0008]
The aspect of the liquid crystal display device of the present invention has a columnar body that performs a function of controlling a gap with the counter substrate, and the columnar body is made of a material mainly composed of any one of a polyimide resin, a polyvinyl alcohol resin, and an acrylic resin. A liquid crystal is filled in a gap formed by contacting the formed color filter and the counter substrate with the columnar body as an inner side, and a transparent conductive film is formed on the columnar body on the counter substrate side of the columnar body. And a single columnar body having a plastic deformation amount with respect to a load of 5 mN of 0.12 μm or less and a bottom sectional area of the single columnar body of less than 200 μm ^2. .
Because of such a liquid crystal display device, a liquid crystal display device with high gap accuracy can be obtained.
[0009]
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a schematic configuration diagram illustrating an example of a color filter for liquid crystal according to the present invention, FIG. 1A is a plan view thereof, and FIG. 1B is a cross section taken along line 1-1 of FIG. FIG. As shown in FIG. 1, a color filter 1 for liquid crystal of the present invention is formed on a transparent substrate 2 and has a color filter layer 3 (R, G, B) and a columnar body 4 made of a colored layer as a basic configuration. Yes.
The columnar body 4 may be formed by stacking the colored layers of R, G, and B as shown in FIG. 1 (B), or R, G, and B as shown in FIG. 1 (C). After forming each colored layer, only the columnar body 4 may be separately formed on the colored layer. When forming separately on a colored layer like FIG.1 (C), forming with a transparent material is preferable so that a colored layer may not be affected. In this case, the transparent material can also serve as the overcoat layer 6.
[0011]
The columnar body may be provided in each colored layer as shown in FIG. 1, or may be provided only in a specific colored layer or at an interval if there is no problem in strength. The columnar body 4 is shown in a square shape in FIG. 1A, but need not be a square shape, and may have another shape such as a circular shape, an oval shape, or a rectangular shape.
Further, a columnar body can be formed on a glass surface other than the non-display portion, and it is preferable to form a similar columnar body on the non-display portion, particularly on the sealing material application portion around the substrate. Conventionally, spacers are also mixed in the sealing material to make the substrate interval constant, but this is because an alternative function can be achieved. The bottom cross-sectional area of the columnar body in these non-display portions is not required to be particularly small.
[0012]
The color filter 1 has a colored layer 3 and a transparent conductive film layer (ITO) 5 on the surface. In the case of FIG. 1B, the transparent conductive film layer 5 can be provided below the columnar body 4, which is advantageous in preventing contact with the counter substrate. When the color filter of the present invention is applied to the IPS system (In-Plane-Switching), the transparent conductive film layer (ITO) 5 is not necessary. Further, if necessary, a black matrix layer and an overcoat layer may be provided. When forming the black matrix layer, the columnar body 4 is preferably formed on the presence of the black matrix in order to effectively use the pixel display portion.
[0013]
When an overcoat layer is formed, both organic and inorganic materials can be used as the overcoat layer. When the overcoat layer is an organic material, the columnar body 4 and the overcoat layer can be formed simultaneously if the overcoat material has photosensitivity in addition to the function of a normal protective film. In this case, for example, it can be achieved by performing double exposure combining the flash exposure of the entire surface and the pattern exposure of the columnar body portion. In addition, the columnar body 4 can be formed after the transparent conductive film 5 is formed. Further, when the overcoat layer is an inorganic material (SiO ₂ or the like), the thickness of the overcoat layer can be set thin. Therefore, when the columnar body 4 is formed by overlapping the colored layers, The colored layer 3 and the columnar body 4 can be protected without reducing the gap amount.
[0014]
In addition, when the black matrix is a resin black matrix and the columnar body 4 is formed thereon, the black matrix layer itself usually has a film thickness of about 1.0 to 2.0 μm, and the columnar body portion is formed thereon. Therefore, the gap amount between the columnar body 4 and the colored layer 3 is widened, which is effective when it is desired to increase the columnar body portion.
[0015]
In the case of forming on the black matrix and having a switching function on the counter substrate side as in the TFT or IPS system, it is desirable to form the columnar body 4 at a position avoiding the TFT on the counter substrate. Further, when the resin black matrix is provided on the TFT, it is desirable to provide the columnar body 4 on the color filter side so as to correspond to the position. Even when the columnar body is formed at a position avoiding the TFT on the counter substrate as described above, there is a risk that the TFT and the columnar body 4 may be in contact with each other due to a positional shift at the time of forming the columnar body 4 or a positional shift at the time of bonding. is there. This causes the possibility of destroying the TFT.
[0016]
Also, when a resin black matrix is provided on the TFT and the columnar bodies 4 are provided on the color filter side so as to correspond to the position, if the number of the columnar bodies 4 in the plane is reduced, the load on the TFT is reduced. This increases the possibility of destroying the TFT. When the TFT is destroyed, the normally white mode often used in the normal TFT method (when no voltage is applied, the TN liquid crystal is in a twisted state of 90 °) It will completely transmit light. This corresponds to the transmitted light of a single color filter. Usually, the luminous transmittance (Y value) is green> red and blue, and green transmits the light most.
For example, if the destroyed TFT corresponds to a green (G) colored portion, since the green Y value is high, the bright spot is more conspicuous than other colors. Therefore, the columnar body 4 is preferably formed in the red (R) and blue (B) portions, avoiding the green colored portion.
[0017]
It is preferable that the height of the columnar body 4 is 1 μm to 8 μm from the surface of the colored layer. This is because when the thickness is 1 μm or less, it takes time to inject liquid crystal into the cell, and thus the process time is limited. Further, the thicker the gap, the slower the response speed, and in the case of forming a column of 8 μm or more, sufficient uniformity in the coated surface cannot be obtained even with a columnar body made of a transparent resin. In addition, it is difficult to achieve in-plane uniformity by forming columnar bodies by superimposing three colors. If it is too high, there is a possibility that a rubbing shadow will occur in the rubbing process of the alignment film, which is not preferable. Usually, the height is preferably about 4 to 6 μm. Further, with respect to the in-plane uniformity of the height of the columnar body 4, in the case of the TFT method, an accuracy of ± 0.3 μm is required from the experience of a normal spacer distribution method.
The columnar bodies 4 are desirably arranged regularly. This is because it is easy to distinguish from defective protrusions in the production of a color filter, and because the force hitting the counter substrate surface can be dispersed by forming columnar bodies at equal intervals.
Furthermore, it is desirable that the outermost surface of the columnar body 4 is flat. This is because, when the surface is flat, it is possible to contact the counter substrate by surface contact and disperse the stress, compared to the point contact of normal spacer beads.
[0018]
When the columnar body 4 is formed by overlapping the colored layers and the overcoat layer is formed of an organic material and only the surface flatness of the colored layer is to be improved, the columnar body 4 is overcoated as a missing pattern. Only the columnar body 4 may be exposed by pattern exposure and development so that the layer is not formed on the columnar body. Further, when the counter substrate has an insulating layer corresponding to the columnar body 4, a transparent conductive film layer may also be formed on the columnar body 4. This is because contact with the counter substrate is prevented.
[0019]
In the present invention, the color filter layer 3 (R, G, B) and the columnar body 4 are formed by a normal photolithography process. That is, after a colored photosensitive material is formed to a predetermined thickness on a transparent substrate or a substrate on which a black matrix is formed by means of a spin coater, a roll coater or the like, exposure, development, and processing steps are performed. The same process is repeated for R, G, and B.
If necessary, a photosensitive positive resist is further coated on the colored photosensitive material, exposed and developed to leave the necessary pattern, and the same steps are repeated for R, G, and B to obtain a predetermined coloring. A portion to be a pixel and a portion to be a columnar body are formed. In the case of using a photosensitive positive resist, the photosensitive positive resist may be left as a columnar body together with the colored layer without being peeled and removed after etching the photosensitive positive resist in the portion to be the columnar body. In this case, the columnar body portion is advantageous in forming the columnar body because it has two layers of a colored layer and a positive resist layer.
In the R, G, B colored layer forming step, only the normal colored layer 3 is formed, the overcoat layer is made photosensitive, and the columnar body is formed only by the overcoat layer as shown in FIG. It is also possible. Further, as described above, it is possible to improve the flatness of the colored pixel portion by forming the overcoat layer only in the non-columnar body portion other than the columnar body portion.
[0020]
【Example】
(Prototype example of color filter)
In order to grasp the material, size, and strength suitable as a columnar body for gap control, the following various prototypes (prototype 1 to prototype 5) were prepared and subjected to comparative tests.
(1) Prototype 1 This is a test for confirming the strength of the columnar body by the composition material, and the resin for the colored layer constituting the columnar body is made of three types of resins, acrylic, polyvinyl alcohol and polyimide. used. Acrylic and polyvinyl alcohol are photosensitive coloring materials, while polyimide is non-photosensitive.
(2) Prototype 2 This is a test to measure the amount of plastic deformation due to the difference in the cross-sectional area of the bottom surface of the columnar body, and is a color having columnar bodies of various sizes and bottom cross-sectional areas using an acrylic colored photosensitive material A filter was produced. The columnar body was formed by superimposing the colored photosensitive material. A prototype with ITO deposited on the surface was also produced. The size and cross-sectional area of these columnar bodies were adjusted by changing the pattern size of the photomask when forming the columnar bodies.
(3) Prototype 3 This is a test to measure the amount of plastic deformation due to the difference in the bottom cross-sectional area of the columnar body, and various sizes and bottom cross-sectional areas using acrylic transparent photosensitive material for the columnar body part. A color filter having a columnar body was produced. For the colored layer, an acrylic colored photosensitive material was used, and only the columnar body portion was an acrylic transparent photosensitive material. Further, the size and the cross-sectional area of these columnar bodies were adjusted by changing the pattern size of the photomask during column formation as described above. A prototype with ITO deposited on the surface was also produced.
(4) Prototype 4 This is a test for examining the load bearing strength of a columnar body, using an acrylic colored photosensitive material, and changing the load by changing the bottom cross-sectional shape of the columnar body to a rectangular shape of 15 x 25 μm. The amount of elastic deformation and plastic deformation of was measured.
(5) Prototype 5 This is a test to measure the breaking load of ITO due to the difference in the cross-sectional area of the bottom surface of the columnar body, and it has a columnar body with various sizes and bottom surface cross-sectional areas using an acrylic colored photosensitive material After producing the color filter, an ITO film was formed on the surface.
Note that no black matrix layer was used in any of prototype 1 to prototype 5.
[0021]
[Prototype 1]
Next, a method for forming a columnar body having a gap function will be described based on trial production 1. Prototype 1 is a case where columnar bodies are formed on the three color lines at regular intervals, and an example of the manufacturing method of this method will be described with reference to FIGS.
FIG. 2 is a diagram showing a first step of an embodiment of the color filter for liquid crystal according to the present invention. 2A is a plan view, and FIG. 2B is a cross-sectional view taken along the line aa in FIG. 2A. Note that the transparent substrate 2 is omitted in FIG. The same applies hereinafter.
As shown in FIG. 2, first, an acrylic negative photosensitive material (“Color Mosaic CR-7001” manufactured by Fuji Hunt Electronics Technology Co., Ltd.) is used as a coloring material on the transparent substrate 2 to form a red (R) stripe. It is formed with a thickness of 3.5 μm. Here, in order to form a columnar body in each color region, in addition to the original red (R) stripe, a red (R) columnar shape is formed at a predetermined position in the green (G) region and the blue (B) region. The body R ₁ is formed to the same thickness of 3.5 μm. For comparison tests, various sizes and areas on the bottom surface parallel to the substrate of the columnar body were formed as shown in Table 3.
[0022]
FIG. 3 is a diagram illustrating the second step. 3A is a plan view thereof, and FIG. 3B is a cross-sectional view taken along the line bb of FIG. 3A.
Next, as shown in FIG. 3, an acrylic negative photosensitive material (“Color Mosaic CG-7001” manufactured by the same company) is used as a coloring material on a transparent substrate, and a green (G) stripe is 3.5 μm thick. Form with. The green (G) stripe covers the red (R) columnar body R ₁ formed in advance at a predetermined location in the green (G) region. The columnar body G ₁ is also formed on R _{1 in} the blue (B) region.
[0023]
FIG. 4 is a diagram showing a third step. 4A is a plan view, and FIG. 4B is a cross-sectional view taken along the line cc of FIG. 4A.
Next, as shown in FIG. 4, an acrylic negative photosensitive material (“Color Mosaic CB-7001” manufactured by the same company) is used as a coloring material on a transparent substrate, and a blue (B) stripe is 3.5 μm thick. Form with. Here, in addition to the original blue (B) stripe, the blue (B) columnar body B ₁ is formed on the red (R) columnar body R ₁ to a thickness of 3.5 μm via the green (G) stripe. Form. The columnar body B ₁ is also formed on the green (G) columnar body G ₁ formed on the red (R) stripe.
[0024]
As a result, the columnar body made of R ₁ + G + B ₁ is formed in the green (G) stripe pattern region, and the columnar body made of R + G ₁ + B ₁ is formed in the blue ( In the stripe pattern region of B), a columnar body made of R ₁ + G ₁ + B was formed protruding from the colored layer surface at a height of 4.7 μm. The above forming method is a method for acrylic photosensitive materials and polyvinyl alcohol-based photosensitive materials which are negative photosensitive materials. Polyimide-based photosensitive materials are coated with a non-photosensitive coloring material with a polyimide precursor and then positively coated thereon. A mold resist material was applied and used. After the exposure, development, etching, and resist stripping treatment, the colored layer was converted to polyimide. As the photomask, a photomask inverted from the negative type was used. In either case, the column height of each layer was adjusted to 4.7 μm.
Further, the mask pattern for forming the columnar body only adds the pattern of the columnar body forming portion to a normal photomask for forming a color filter, and therefore there is no need to add other special elements.
The above prototypes are acrylic (“Color Mosaic” manufactured by Fuji Hunt Electronics Technology Co., Ltd.), polyvinyl alcohol (“Prototype” manufactured by The Inktec Co., Ltd.), polyimide (BREWER SCIENCE Inc. “Prototype”). The three types of colored photosensitive materials were prepared.
[0025]
[Prototype 2]
A color filter substrate was produced by the same production method as in Prototype 1. However, to measure the amount of plastic deformation due to the difference in the bottom cross-sectional area of the columnar body using the same acrylic colored photosensitive material as in Prototype 1, the bottom cross-sectional size of the columnar body varies from 5 × 15 μm to 25 × 25 μm. It was. These sizes can be adjusted by changing the pattern size of the photomask when forming the columnar body. A prototype in which a transparent conductive film layer 5 (thickness: 1500 mm) made of ITO was provided on the colored layer was also prototyped.
[0026]
[Prototype 3]
The columnar body was formed of a transparent photosensitive material, and the bottom surface cross-sectional size of the columnar body was varied from 5 × 15 μm to 25 × 25 μm in order to measure the amount of plastic deformation due to the difference in the bottom surface cross-sectional area. These sizes can be adjusted by changing the pattern size of the photomask when forming the columnar body.
[0027]
Based on prototype 3, another method for forming a columnar body having a gap function will be described. Prototype 3 is a case where columnar bodies are formed on the three color lines at regular intervals, and an example of the manufacturing method of this method will be described with reference to FIGS.
FIG. 5 is a diagram showing a first step of another embodiment of the color filter for liquid crystal according to the present invention. 5A is a plan view thereof, and FIG. 5B is a cross-sectional view taken along the line dd in FIG. 5A.
First, as shown in FIG. 5, a negative acrylic colored photosensitive material (“Color Mosaic” manufactured by Fuji Hunt Electronics Co., Ltd.) is used on the transparent substrate 2 to form red (R) stripes, green (G). A colored layer 3 composed of a stripe of blue and a stripe of blue (B) was formed. The thickness of each colored layer was 1.5 μm. These forming processes are the same as those of a normal color filter. When the columnar body is formed by overlapping the colored layers, the colored layer itself needs to be formed into a thick film. However, when the columnar body is formed of a transparent photosensitive material after the colored layer 3 is formed, the colored layer is thinned. There are advantages that can be done.
[0028]
FIG. 6 is a cross-sectional view showing the second step. 6A is a plan view thereof, and FIG. 6B is a cross-sectional view taken along line ee of FIG. 6A.
Next, as shown in FIG. 6, the columnar body 4 is formed on the colored layer using a transparent photosensitive material (acrylic photosensitive material). In order to form at a predetermined column height, a 5.5 μm-thick coating layer was formed, only the columnar body 4 portion was exposed through a photomask, and predetermined development processing and drying were performed. The columnar body 4 was formed with a height of 4.7 μm on the colored layer.
FIG. 7 is a diagram showing a third step. Next, a transparent conductive film layer 5 made of ITO is formed on the columnar body 4 and the colored layer 3 by sputtering. The film thickness of the transparent conductive film layer was 1500 mm.
[0029]
[Prototype 4]
A color filter substrate was produced by the same production method as in Prototype 1. However, using the same acrylic colored photosensitive material as in Prototype 1, the bottom cross-sectional size of the columnar body is 15 x 25 μm, and the total deformation amount and plastic deformation amount when the load (load) applied to the columnar body is changed are measured. The amount of elastic deformation was determined.
[0030]
[Prototype 5]
A color filter substrate with a transparent conductive film layer made of ITO was produced by the same production method as in Prototype 1. However, the same acrylic colored photosensitive material as in Prototype 1 is used, and the ITO breakdown load due to the difference in the cross-sectional area of the bottom of the columnar body is measured. Therefore, the cross-sectional size of the bottom of the columnar body varies from 5 × 15 μm to 25 × 25 μm. It was. These sizes can be adjusted by changing the pattern size of the photomask when forming the columnar body. The transparent conductive film layer was formed to a thickness of 1500 mm on the entire surface including the columnar body by sputtering after producing a color filter with columnar bodies.
[0031]
(Evaluation of color filter)
[Prototype 1]
The strength of the colored layer portion (the portion without the columnar body) of the color filter according to trial production 1 was measured by the following method using an ultra micro hardness meter.
<Measurement method>

FIG. 8 is a diagram for explaining a load test for obtaining a dynamic hardness value. First, as shown in FIG. 8 (A), a load up to a set load of 5.0 mN is applied to the colored layer with a triangular pyramid indenter (FIG. 8 (C)) whose tip is a triangular pyramid at the above load speed. After reaching the load, the load was held for 5 seconds, and then the dynamic hardness value was obtained from the load (5.0 mN) and the indentation depth (FIG. 8B).
[0032]
The results are as shown in Table 1. A tendency of acrylic <polyvinyl alcohol <polyimide was observed. In addition, the measurement unit in Table 1 shows a value for dynamic hardness.
[Table 1]

[0033]
The dynamic hardness of the columnar body portion of the color filter according to prototype 1 was measured by the same method as described above. The results are as shown in Table 2. In this case as well as the colored layer, the tendency of acrylic <polyvinyl alcohol <polyimide was observed. In addition, the measurement unit in Table 2 shows a value for dynamic hardness.
From this, it was confirmed that the hardness of the columnar body depends on the resin material used for the colored layer. Compared with the acrylic type, the polyvinyl alcohol type has a columnar strength of 1.13 times, and the polyimide type has a strength of 1.27 times.
This is because, when a columnar body having a gap control function is formed on a color filter, it is necessary to provide 100 columnar bodies for a certain area, whereas in the case of polyvinyl alcohol system, 88 columns and in polyimide system It means that the number of 78 is sufficient. In Table 2, “on R” means a columnar body formed on the red colored layer.
[0034]
[Table 2]

[0035]
[Prototype 2]
The strength of the columnar body portion of the color filter according to trial production 2 was measured by the following method using an ultrafine hardness meter.
<Measurement method>

[0036]
FIG. 9 is a diagram for explaining a load test for obtaining the plastic deformation amount and the elastic deformation amount. FIG. 9A shows the time passage and the load at the time of the test. First, using a cylindrical indenter, a load is applied to the columnar body portion at a constant load speed until the set load reaches 5.0 mN. Next, the set load is held for 5 seconds. Furthermore, unloading is performed at a constant unloading speed (same as the loading speed) to return to the no-load state. This completes one measurement. Actually, as shown in FIG. 9B, the pushing depth increases to D1 up to the set load at the time of loading, and the pushing depth returns to D2 at the time of unloading. Since D2 is the amount of deformation after unloading, it represents the amount of plastic deformation, and D1 represents the total amount of deformation at the set load. Therefore, by subtracting D2 from D1, the amount of elastic deformation at the set load can be calculated.
[0037]
Table 3 shows the column size of the columnar body formed on the colored layers of R, G, and B, and the measurement results when a load of 5 mN as a measurement condition is applied to the columnar body.
[0038]
[Table 3]

The unit of column size, D1, D2, elastic deformation and plastic deformation is μm.
The column area is μm ^{2 and the} load is mN.
The same applies to the following tables.
[0039]
As a result, as shown in Table 3, when attention is paid to the columnar body formed on the colored layer R, the total deformation amount (D1) changes from 100 μm ² to 200 μm ² as the column area increases. I can see it going. This change also shows the same change in the amount of plastic deformation (D2). When the column area of the columnar body is 200 μm ² or more, the amount of plastic deformation is 0.05 μm or less. Next, paying attention to the column area of 200 μm ² , the amount of plastic deformation of each colored layer is about 0.04 μm, indicating that the values are almost the same. The structure of the columnar body is different in each layer as shown in FIG. That is, the side surface of the column is not covered with the colored layer compared with the columnar body formed on the other colored layer, and the two-layer structure of the columnar body is directly loaded. It becomes. Therefore, the amount of plastic deformation at 75 μm ² is worse for the columnar body formed on the R layer than that formed on the other layers. However, those formed with 200 μm ² or more as described above show almost the same value regardless of the difference in the structure of the columnar bodies.
[0040]
From this, it can be explained that the plastic deformation amount can be suppressed to 0.05 μm or less by having a column area of 200 μm ² or more. That is, when the bottom cross-sectional area of the columnar body is 200 μm ² or more, the amount of plastic deformation can be suppressed to 0.05 μm or less without being affected by the configuration of the columnar body.
When a columnar body having an area of 200 μm ² is formed in a square, one side is about 14 μm, but there is no limitation as long as it is 200 μm ² or more. If it is large, the image quality is deteriorated, and it is desirable that the columnar body is not recognized at a clear distance. Usually, the resolution of the human eye (minimum size that can detect the presence of a point) is about 1 minute in angle, and when calculated based on this, the minimum when viewing the liquid crystal display from a distance of about 30 cm The resolution is about 87 μm. Accordingly, when the diagonal is a square having an area of 87 μm, the area is about 7570 μm ² .
[0041]
[Table 4]

[0042]
Table 4 shows measured values of the prototype 2 in which an ITO layer is provided in the R layer. It can be seen that the total deformation amount (D1) changes with 100 μm ² and 200 μm ² as the boundary, as in Prototype 2 in Table 3 where no ITO layer is provided. In addition, the amount of elastic deformation is almost the same as that in Table 3, whereas the amount of plastic deformation is not dependent on the column size, and is about 0.1 μm.
From these facts, it can be seen that the amount of elastic deformation depends on the underlying colored columnar body, and the amount of plastic deformation depends on the ITO layer, which is an inorganic film. In this case, if the columnar body is designed assuming a deformation amount of 0.12 μm or less with respect to a load of 5 mN, the columnar body can be arranged without dependency on the column size. Further, as will be described later, the ITO film breaking load is much larger, and it is considered that the practical trouble in the liquid crystal display device due to the destruction of the ITO does not occur.
[0043]
[Prototype 3]
The strength of the columnar body portion of the prototype color filter according to prototype 3 was measured using an ultra-micro hardness meter in the same manner as in prototype 2. The results are shown in Table 5. In addition, this measurement was performed in the state (FIG. 6B) before providing the ITO layer.
[0044]
[Table 5]

[0045]
From Table 5, it can be seen that as the column area is increased, the total deformation (D1) changes with 100 μm ² and 200 μm ² as the boundary. This change also shows the same change in the amount of plastic deformation (D2). If the column area of the columnar body is 200 μm ² or more, the amount of plastic deformation is 0. 0 even if the columnar body is made of a transparent photosensitive material. It becomes 05 μm or less.
Table 6 shows the measured values of the prototype 3 provided with the ITO layer.
[0046]
[Table 6]

[0047]
It can be seen that the total amount of deformation (D1) changes with 100 μm ² and 200 ² μm as the boundary, as in Prototype 3 in Table 5 without the ITO layer. Further, the amount of elastic deformation shows almost the same value as compared with Table 5, whereas the amount of plastic deformation shows a value around 0.1 μm without any dependency on the column size. From these facts, it is understood that the amount of elastic deformation depends on the underlying transparent columnar body, and the amount of plastic deformation depends on the ITO layer, which is an inorganic film, as in Prototype 2. In this case, if the columnar body is designed assuming a deformation amount of 0.12 μm or less with respect to a load of 5 mN, the columnar body can be arranged without depending on the column size.
[0048]
[Prototype 4]
Next, the load test of the columnar body portion of the prototype color filter according to prototype 4 was performed by the following method. In this case, the cross-sectional area of the columnar body 4 is 15 × 25 μm as described above. The load was changed as a parameter, and the amount of elastic deformation and plastic deformation were measured.
<Measurement method>

[0049]
FIG. 10 is a graph showing the amount of deformation with respect to the load of the columnar body and measured numerical values.
FIG. 10A is a graph showing the result of measuring the columnar body portion of the color filter of Prototype 4, and FIG. 10B is a table showing the measured numerical values.
As is apparent from the graph, when a load of 100 mN or more is applied, the slopes of elastic deformation and plastic deformation are the same. This shows that the columnar body is destroyed. That is, it can be seen that a 15 × 25 μm columnar body can withstand a load resistance of 100 mN (10.2 gf) with one column, and is a practically sufficient value.
However, there is a limit to how practical this columnar body is. As is apparent from the graph of FIG. 10, when a load of 100 mN or more is applied, the amount of deformation changes rapidly. For example, even when the height of the columnar body is 4 μm at the time of work, when a load of 200 mN is applied, the plastic deformation is 0.5 μm, and the gap control is 3.5 μm. In order to increase the height of the pillars by superimposing the colored layers, it is generally necessary to increase the thickness of the colored layers, which makes the design and process very difficult. On the other hand, at a load of 100 mN or less, the plastic deformation is 0.2 μm or less, and the columnar body can be designed in consideration of the amount of deformation from the beginning.
[0050]
Of course, after forming the colored layer, when the columnar body is formed by patterning the transparent resin, it is only necessary to design the required columnar body height in consideration of the amount of composition deformation with respect to the load as described above. .
As will be described later, from Table 8, the amount of plastic deformation of one micropearl for a load of 5 mN is 0.5 μm, while the columnar body has a load of 200 mN as described above. In other words, it can be said that it can withstand a load of about 40 times. This also shows that the value is practically sufficient.
[0051]
[Prototype 5]
Next, the ITO destruction load test of the columnar body portion of the color filter according to the prototype 5 was performed by the following method. The cross-sectional areas of the columnar bodies in this case are four types of 10 × 10, 15 × 15, 20 × 20, and 25 × 25 μm. The load was changed with respect to these columnar bodies, the subsequent substrate was observed with a microscope, the presence / absence of ITO was confirmed, and a load exceeding the destruction was applied.
<Measurement method>

[0052]
FIG. 11 is a diagram showing the result of the ITO destructive load test on the columnar body portion. FIG. 11 is a plot of the total deformation under the above test load. As shown in the figure, ITO is destroyed at 200 mN at 10 × 10 μm, 350 mN at 15 × 15 μm, 500 mN at 20 × 20 μm, 750 mN at 25 × 25 μm. It was confirmed that Further, as is clear from the graph, it can be confirmed that an inflection point exists at the time of ITO destruction. It can also be seen that the fracture inflection point varies depending on the column size. In any size, the breaking load of ITO is usually much higher than the load applied to the columnar body, and it was confirmed that this columnar body sufficiently functions as a gap control material.
[0053]
(Comparative example)
Next, the amount of plastic deformation of the spacer when a spherical spacer was used for a normal color filter was measured. That is, on a color filter substrate without a columnar body formed in the same manner as in trial production 1, a spacer having an average particle diameter of 5.00 ± 0.05 μm and a standard deviation of 0.19 ± 0.01 μm (“Micro” manufactured by Sekisui Fine Chemical Co., Ltd.) About what sprinkled pearl SPN-205 "), it measured by the same measuring method as trial production 2. The test method is as follows. The spacer is hereinafter referred to as “micropearl”.
[0054]
(Micropearl test method)
A small amount of micropearl is added to IPA (Isopropyl Alcohol Pure Chemical Co., Ltd.) and stirred sufficiently to prepare a dispersion. The cloth piece is immersed in the IPA solution in which micropearls are dispersed using tweezers. The cloth piece is rubbed against a color filter to attach micropearls. Thereafter, the IPA is dried at room temperature.
With respect to one colored pixel, one with a micropearl attached thereto was confirmed with a microscope and set as a measurement target. However, for Table 10, one micropearl and two micropearls were measured for comparison.
[0055]
The results are as shown in Tables 7 to 10, but as shown in Tables 7 and 8, the amount of plastic deformation of the micropearl with respect to a load of 5 mN is about 0.5 to 0.6 μm. It can be seen that the amount of plastic deformation is large by an order of magnitude compared to the columnar body.
[0056]
[Table 7]

[0057]
[Table 8]

[0058]
[Table 9]

[0059]
[Table 10]

[0060]
Next, when Table 8 and Table 9 are compared, the amount of plastic deformation of the standard color filter + ITO + micropearl in Table 8 is about 0.51 μm, whereas a sample in which micropearl is adhered on the glass ( In Table 9), the amount of plastic deformation is about 0.42 μm. The difference is the deformation amount contributing to the color filter itself, which is 0.1 μm or less, and it can be estimated that most of the deformation is micropearl deformation. When the load is changed as shown in Table 9, it can be understood that the micro pearl is deformed by changing both the total deformation amount and the plastic deformation amount.
In order to confirm that the number of micropearls affects the amount of plastic deformation, measurement was performed on a sample having two micropearls per pixel. The results are as shown in Table 10. In order to reduce the amount of plastic deformation, it is necessary to spray a plurality of micropearls on one pixel.
[0061]
Here, it is determined how much load is applied to each spacer. Assume that a load of 10 kgf is applied to the entire 11.3 inch (diagonal length of the screen) panel. In the case of a 11.3 inch panel, both sides are typically 172.8 × 230.4 mm, and the area is approximately 40,000 mm ² (400 cm ² ). Since 100 to 200 spacers are normally sprayed on 1 mm ² , the total number of spacers is 4 to 8 million. If 10 kgf is divided by this number, the load applied to one spacer is 1.25 mgf to 2.50 mgf.
[0062]
When calculated with more specific numerical values, it is said that the pressure applied to the substrates is 0.45 to 0.55 kg / cm ² . If the pressure applied to the substrates is 0.5 kg / cm ² , the force applied to the entire substrate is 200 kgf. If the load applied to the one spacer is calculated with this number, it is 25 to 50 mgf.
[0063]
Here, a test load of 5.0 mN (0.51 gf) corresponds to a load applied to 10 to 20 spacers. This corresponds to the spacer amount existing at 0.1 mm ² from the above, and considering that the size of one pixel of S-VGA (Super Video Graphics Array) is 288 μm × 96 μm, it corresponds to 3.6 pixels. To do.
In other words, a test load of 5.0 mN (0.51 gf) corresponds to about three pixels of RGB in a normal spacer, considering the inch size of the panel currently used and the display standard.
[0064]
As described above, it is confirmed that the prototype 2 and 3 of the color filter having a columnar body formed of an acrylic coloring material have the ability for plastic deformation higher than that of micropearls and are sufficiently effective as a gap control material. It was.
On the other hand, in the color filter of trial production 1 in which a columnar body is formed with acrylic, polyvinyl alcohol, and polyimide coloring materials, the columnar body with acrylic coloring material is lower in hardness than polyvinyl alcohol and polyimide. I was able to confirm. Also from this fact, it is considered that if the acrylic material is sufficiently effective as the gap control material, the other two kinds of materials can sufficiently exhibit their functions.
[0065]
(Examples relating to liquid crystal display devices)
From the above prototype results, a columnar body with a bottom cross-sectional area of 15 × 15 μm made of acrylic material is provided on the colored layer, and a columnar body of 50 × 50 μm is also provided on the sealing material application part around the color filter substrate. The color filters for liquid crystal (two types of columnar bodies made of colored photosensitive material according to trial production 1 and those of columnar bodies made of transparent photosensitive material according to trial production 3) were prepared, and a liquid crystal display device was assembled using each.
First, a polyimide-based alignment film was applied on the TFT substrate manufactured by the above-described prototype method and subjected to alignment treatment to form a counter substrate. Similarly, after applying a polyimide-based alignment film on the color filter side and performing an alignment treatment, a sealant ("Strectbond XN-21-SB" manufactured by Mitsui Toatsu Chemical Co., Ltd.) is formed on the outer periphery on the color filter substrate side. ]) Was applied, the counter substrate and the color filter substrate were bonded together, and the liquid crystal injection part was left and sealed.
Finally, the cell substrate was filled with liquid crystal and sealed, and a predetermined driving circuit and a lighting device were provided to complete a liquid crystal display device.
In the completed liquid crystal display devices, the distance between the counter substrate and the color filter was kept at a constant interval, and good results were obtained in the image display function test.
[0066]
【The invention's effect】
The present invention has the following remarkable effects.
(1) By selecting the material, size, and strength of the columnar body serving as an alternative part of the spacer, it is possible to sufficiently provide the same function as that of the conventional spacer.
{Circle around (2)} In the case of a columnar body made of a colored photosensitive material, by changing the mask pattern, a columnar body having a uniform interval can be formed without adding a new process. In the case of a columnar body made of a transparent sensitive material, a columnar body having an arbitrary height can be formed with high accuracy.
{Circle around (3)} In any case, since the columnar bodies are formed and fixed in a certain regular relationship, they do not cause movement like a spacer and impair image display, and there is no fear of light scattering.
(4) By providing a columnar body in the seal portion around the color filter substrate, it is not necessary to include a spacer material in the seal material.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram illustrating an example of a color filter for liquid crystal according to the present invention.
FIG. 2 is a diagram showing a first step of an embodiment of the color filter for liquid crystal according to the present invention.
FIG. 3 is a diagram showing a second step.
FIG. 4 is a diagram showing a third step.
FIG. 5 is a diagram showing a first step of another embodiment of the color filter for liquid crystal according to the present invention.
FIG. 6 is a diagram showing a second step.
FIG. 7 is a diagram showing a third step.
FIG. 8 is a diagram illustrating a load test for obtaining a dynamic hardness value.
FIG. 9 is a diagram for explaining a load test for obtaining a plastic deformation amount and an elastic deformation amount.
FIG. 10 is a graph showing the amount of deformation with respect to the load of a columnar body and measured numerical values.
FIG. 11 is a diagram showing a result of an ITO destructive load test on a columnar body portion.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Color filter for liquid crystals 2 Transparent substrate 3 Colored layer or color filter layer 4 Columnar body 5 Transparent conductive film layer 6 Overcoat layer

Claims (11)

Has a number of columnar body performing gap control function between the color filter and the opposite substrate to the colored layer, and, the columnar body is a color filter formed by photolithography, the columnar body is a polyimide resin, polyvinyl alcohol resins state, and are not formed by material mainly to either acrylic resin, the columnar body has a transparent conductive film on the pillar, the plastic deformation against the load 5mN single columnar body A liquid crystal color filter having an amount of 0.12 μm or less and a bottom cross-sectional area of the single columnar body of less than 200 μm ² . 2. The color filter for liquid crystal according to claim 1, wherein the columnar body is formed of a transparent photosensitive material. 2. The color filter for liquid crystal according to claim 1, wherein the columnar body is formed by superposing colored layers of the color filter. LCD color filters請Motomeko 3 according to claims 1, wherein the top portion of the columnar body is flat. LCD color filters請Motomeko 4 according to claims 1, wherein the columnar body is formed only at a position corresponding to a particular color layer. The height of the columnar body, a liquid crystal color filter of claim 1請Motomeko 5 Symbol mounting, characterized in that there is 1μm or more from the surface of the colored layer is 8μm or less. LCD color filter of claims 1請Motomeko 6 Symbol mounting, characterized in that the columnar bodies are arranged on the black matrix. 8. The color filter for liquid crystal according to claim 1, wherein the columnar bodies are regularly arranged. A color filter having a columnar body that performs a function of controlling a gap with the counter substrate on a colored layer , the columnar body being formed of a material mainly composed of polyimide resin, polyvinyl alcohol resin, or acrylic resin; A liquid crystal is filled in a gap formed by contacting the counter substrate with the columnar body as an inner side, and a transparent conductive film is provided on the columnar body on the counter substrate side of the columnar body. A liquid crystal display device characterized in that the amount of plastic deformation of the columnar body with respect to a load of 5 mN is 0.12 μm or less, and the bottom sectional area of the single columnar body is less than 200 μm ² . The columnar body is a liquid crystal display device according to請Motomeko 9, characterized in that it is formed by the superposition of the colored layers. 11. The liquid crystal display device according to claim 9 , wherein a columnar body that performs a function of controlling a gap with the counter substrate is also formed on a sealing material application portion around the substrate.

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