JP2004240136A - Method for manufacturing pattern layer formed body with various levels - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a pattern layer formed body with various levels by which a pattern layer of various levels comprising a combination of patterns of various levels can be manufactured at the same time by using one material. <P>SOLUTION: The method includes: a photosensitive layer forming process of applying a photosetting resin composition on a substrate to form a photosensitive layer; an exposure process of exposing the photosensitive layer through a mask which has a light shielding layer to interrupt transmission of light and an opening formed along the pattern of the pattern layer with various levels and which has a filter absorbing ≥40% of light in the wavelength range from 200 nm to 500 nm disposed in a part of the opening; and a pattern layer forming process of developing the exposed photosensitive layer to form the pattern layer with various levels in which the photosensitive layer corresponding to the region where the filter is disposed in the opening of the mask gives a part with a low level. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【００４３】
この光硬化型樹脂組成物の塗布方法は、一般的に塗工液を基板の全面に塗布する方法であれば特に限定されるものではなく、具体的には、スピンコーティング法、キャスティング法、ディッピング法、バーコート法、ブレードコート法、ロールコート法、グラビアコート法、フレキソ印刷法、スプレーコート法等の塗布方法が用いられる。
【００４４】
本発明は、上記塗布方法を用いて基板上に上述した光硬化型樹脂組成物を塗布することにより感光層を形成する。
【００４５】
（２）基板
本工程において、上述した光硬化型樹脂組成物は基板上に塗布される。このような基板としては、一般的に各種高低パターン層形成体の基板として用いられる材料であれば特に限定はされるものではないが、本発明における高低パターン層形成体の用途として液晶ディスプレイ用基板が好ましいことから、透明性を有する基板であることが好ましい。このような基板の材料として例えば、例えば石英ガラス、パイレックス（登録商標）、合成石英板等の可撓性のない透明なリジット材、あるいは透明樹脂フィルム、光学用樹脂板等の可撓性を有する透明なフレキシブル材等を用いることができる。
【００４６】
２．露光工程
次に、露光工程について説明する。本発明における露光工程とは、光の透過を遮る遮光層と、上記高低パターン層のパターンに沿って形成された開口部とを有し、所定の波長を所定の割合で吸収するフィルターが、上記開口部の一部に配置されているマスクを用い、上記マスクを介して、上記感光層を露光する工程である。例えば、図１（ｂ）に示すように、遮光層３と、開口部４とを有し、開口部４の一部にフィルター５が配されているマスク４を準備し、当該マスク４を介して、光硬化型樹脂組成物から形成された感光層２に露光する工程である。
【００４７】
このような本工程において用いられるマスクについて説明する。
【００４８】
（１）マスク
本発明におけるマスクは、透明基板と、透明基板上に形成され光の透過を遮る遮光層と、後述する高低パターン層のパターンに沿って形成された開口部とを有するものであり、かつ、上記開口部の一部には、所定の範囲内の波長を所定の割合で吸収するフィルターが配されているものである。このような本発明におけるマスクを構成する各部材について説明する。
【００４９】
▲１▼ 遮光層
遮光層は、本工程において露光する際に、感光層の未露光領域となる領域上に光が照射されることを防止するため、光の透過を妨げる役割を担っている。このような遮光層を形成する材料としては、一般的に遮光層として用いられる材料であれば特に限定されるものではなく、遮光性に優れた材料が好適に用いられる。
【００５０】
本発明においては、中でも金属クロム材料を好適に用いることができる。さらに、その上に酸化クロム材料を成膜してもよい。
【００５１】
このような遮光層の成膜方法としては、真空蒸着法、スパッタ法、ＣＶＤ法等が挙げられる。特にこの中でも、スパッタ法により成膜することが好ましい。
【００５２】
また、このような遮光層に開口部を形成する方法としては、例えば、透明基板上に上述した塗布方法により成膜された遮光層上にレジストを積層し、当該レジストに電子線またはレーザ等により、高低パターン層のパターンに沿って描画する。その後、レジストを現像すると、パターン状にレジストが形成される。当該パターン状に形成されたレジストを利用してエッチングすると、レジストが除去され露出している部分の遮光層がエッチングされ、当該エッチングされた部分が開口部となる。
【００５３】
本発明においては、上述した感光層が光硬化型であることから、上述した方法により形成されるマスクの開口部は、高低パターン層のパターンに沿って形成される。
【００５４】
▲２▼ フィルター
本発明におけるマスクは、開口部の一部にフィルターが配されていることを特徴とする。このようなフィルターは、所定の範囲内の波長を所定の割合で吸収する性質を有するものであれば特に限定されるものではない。具体的には、吸収する光の波長が、２００ｎｍ〜５００ｎｍの範囲内である必要があり、その中でも、３００ｎｍ〜４５０ｎｍの範囲内であることが好ましい。さらに、上記範囲内の波長を吸収する割合としては、４０％以上とする。本発明における光硬化型樹脂組成物に露光する際に使用する光源に対して、上述した範囲内の波長を上記割合で吸収するフィルターであれば、フィルターの有無により、露光される光に含まれる波長に違いを生じさせることができるからである。
【００５５】
このようなフィルターを形成する材料としては、上述した範囲内の波長を上記範囲吸収する性質を有する材料であれば特に限定はされない。その中でも、上述した範囲外の波長に対しては、透光性に優れた材料であることが好ましい。具体的には、顔料、染料等の色材を含むフィルム、顔料、染料等の色材を含む感光性樹脂等を挙げることができる。
【００５６】
さらに、本発明におけるフィルターの形成方法としては、上述した材料を用いて、薄膜状に形成することが可能な方法であれば特に限定はされないが、具体的には、顔料、染料等を分散した粘着性フィルムを必要な領域にラミネートする方法、顔料、染料等の色材を含む感光性樹脂を必要な領域に形成する方法等を挙げることができる。
【００５７】
さらに、本発明においては、上述した範囲内の波長の光を上記範囲吸収するフィルターのうち、光の透過率が異なるフィルターを２種以上用いてもよい。フィルターは光の透過率が異なることにより、上述した光硬化型樹脂組成物に反応性の違いを生じさせることができ、その結果、フィルターの有無に加えて、光の透過率が異なるフィルターによるパターンが設けられることにより、フィルターを介して露光された領域から形成される高低パターン層の低部を、２種以上の高さの異なる組み合わせからなる低部とすることができ、より多様な高さの違いによる高低パターン層を形成することができるのである。
【００５８】
例えば、フィルターの有無により、高部および一種類の低部からなる高低パターン層を形成する際や、フィルターの有無に加えて光の透過率が異なる２種以上のフィルターを設けることにより、２種以上の高さの異なる組み合わせからなる低部を有する高低パターン層を形成する際には、予め、フィルターの有無により生じる現像後の残膜率の違いや、光の透過率が異なるフィルターを用いた場合の現像後の残膜率の違いを実験により求めておくことにより、高低パターン層の調整を行うことができる。
【００５９】
図５に、２００ｎｍ〜５００ｎｍの光の透過率が１０％および４０％である２種類の黄色フィルターを用いた場合およびフィルターを介さずに露光した場合に、露光量の変化による膜厚の違いを計測した結果を示す。
【００６０】
なお、黒丸は、フィルターを介さずに露光した場合の膜厚を示し、黒三角は、２００ｎｍ〜５００ｎｍの光の透過率が４０％である黄色フィルターを介して露光した場合の膜厚を示し、黒四角は、２００ｎｍ〜５００ｎｍの光の透過率が１０％である黄色フィルターを介して露光した場合の膜厚を示している。
【００６１】
図５の結果から、黄色フィルターの有無かつ光の透過率の違いにより、各々の露光量において膜厚に違いが生じていることが分かる。すなわち、このような実験結果に基づいて、所望の膜厚の差を生じさせるフィルターおよび露光量を選択することにより、所望の膜厚およびその差を有する高部および低部からなる高低パターン層を形成することができる。
【００６２】
（２）露光
本工程においては、上述したマスクを介して、感光層にパターン露光を行う。この際に使用される光源としては、光硬化型樹脂組成物を硬化させることが可能な光を照射することができる光源を挙げることができ、具体的には、紫外光を含む光の光源を用いることができる。このような紫外光を含む光の光源としては、例えば、水銀ランプ、メタルハライドランプ、キセノンランプ等を挙げることができる。また、露光に際しての光の露光量は、フィルターが配置されていない開口部に該当する部分の感光層を硬化するのに十分な露光量とする。
【００６３】
３．高低パターン層形成工程
次いで、高低パターン層形成工程について説明する。本発明における高低パターン層形成工程とは、上述した露光工程により露光された感光層を現像し、前記マスクの開口部のうちフィルターが配置されている領域に該当する感光層が低部となる高低パターン層を形成する工程である。
【００６４】
本発明においては、上述した露光工程の際に、開口部の一部にフィルターを配したマスクを介してパターン露光していることから、感光層において露光された露光領域であっても、フィルターの有無により感光層には反応性に違いが生じている。従って、本工程においてこのような感光層を現像すると、未露光領域の感光層は除去される一方で、露光領域の感光層は、フィルターの有無により膜厚が異なる高部および低部となり、当該高部および低部からなる高低パターン層を形成する。以下、本工程により形成される高低パターン層について説明する。
【００６５】
（高低パターン層）
本発明における高低パターン層とは、高さが異なる高部および低部がパターン状に組み合わされてなる層である。
【００６６】
このような高低パターン層を構成する高部は、高低パターン層の中で最も膜厚が厚い部分であり、上述した露光工程において、フィルター無しの開口部に該当する感光層から形成される部分を示している。高部は、光源から照射された光がそのまま露光された感光層から形成されているため、後述する低部よりも、上述した露光工程において硬化が速やかに進行し、現像後の残膜率が最も高くなるのである。
【００６７】
一方、低部は、高低パターン層のうち、上述した高部を除いた部分であり、フィルターが配置された開口部に該当する感光層から形成される部分を意味する。低部は、フィルターを通過した光が露光されているため、上記高部よりも、上述した露光工程において硬化が緩やかに進行し、現像後の残膜率が、高部と比較し低くなるのである。このような低部は、高さが均一な低部であってもよく、また、複数の高さの違う組み合わせからなる低部であってもよい。すなわち、上述したマスクにおいて、光の透過率が同一であるフィルターが開口部の一部に配されている場合には、均一な高さを有する低部が形成されるが、光の透過率が異なる２種以上のフィルターを用いた場合には、低部の中でも、２種以上の高さの違いが生じるからである。このような低部は、高低パターン層形成体の用途に応じて選択される。
【００６８】
このような高部および低部における膜厚の差、および各々の膜厚は、高低パターン層形成体の用途に応じて決定される。
【００６９】
本工程において用いる現像液としては、用いる光硬化型樹脂組成物に応じて決められる。具体的には、水酸化カリウム水溶液、炭酸ナトリウム水溶液、炭酸水素ナトリウム水溶液、ＴＭＡＨ水溶液等を挙げることができる。なお、光硬化型樹脂組成物が、基板以外の他の部材上に形成されている場合には、そのような部材を溶解させることがない現像液を用いる必要がある。
【００７０】
４．得られる高低パターン層形成体
次に本発明の高低パターン層形成体の製造方法により得られる高低パターン層形成体について説明する。本発明における高低パターン層形成体とは、基板と、前記基板上に形成され、高さの異なるパターンが組み合わされてなる高低パターン層とを有するものである。
【００７１】
このような高低パターン層形成体の用途としては、同一材料からなり高さの異なる部材を有するものであれば特に限定はされない。具体的には、液晶ディスプレイ用基板を挙げることができる。
【００７２】
なお、ここでいう液晶ディスプレイ用基板とは、内部に液晶層を挟持し、液晶ディスプレイを構成するものであるが、例えば、カラーフィルタを有するカラーフィルタ側基板、薄膜トランジスタ等を有するアレイ側基板、さらには、薄膜トランジスタ上に直接カラーフィルタが形成されているオンチップ型の基板等を挙げることができる。
【００７３】
本発明においては、液晶ディスディスプレイ用基板の中でも、モノクロ液晶ディスプレイ用基板およびＭＶＡモード液晶ディスプレイであることが好ましい。
【００７４】
モノクロ液晶ディスプレイ用基板では、モノクロ液晶ディスプレイの表示領域である画素部に位置する画素スペーサと、モノクロ液晶ディスプレイの表示領域外である外周部に位置する外周スペーサとを、高さを違えて形成する必要がある場合があり、このような場合に、本発明における高低パターン層を画素スペーサおよび外周スペーサに活用することにより、同一材料で同時に画素スペーサおよび外周スペーサを形成することができ、製造効率を向上させることができる。
【００７５】
一方、ＭＶＡモード液晶ディスプレイは、液晶の配向を制御する配向制御突起と、対向基板との間隔を一定に保持するＭＶＡ用柱状スペーサとが、同一材料で異なるパターンおよび異なる高さに形成されるものであることから、このような配向制御突起およびＭＶＡ用柱状スペーサを高低パターン層とすることにより、製造効率上有利となる。
【００７６】
以下、モノクロ液晶ディスプレイ用基板の製造方法およびＭＶＡモード液晶ディスプレイの製造方法について説明する。
【００７７】
Ｂ．モノクロ液晶ディスプレイ用基板の製造方法
本発明のモノクロ液晶ディスプレイ用基板の製造方法は、上述した高低パターン層形成体の製造方法を用いたモノクロ液晶ディスプレイ用基板の製造方法であって、前記高低パターン層が、前記モノクロ液晶ディスプレイの表示領域に位置する画素スペーサおよび前記モノクロ液晶ディスプレイの表示領域外に位置する外周スペーサであり、
パターン状に形成されたブラックマトリクスと、前記パターン状に形成されたブラックマトリクスを被覆するように形成された保護層とを有する基板を準備する基板準備工程と、
光硬化型樹脂組成物を前記基板上に塗布し、感光層を形成する感光層形成工程と、
光の透過を遮る遮光層と、前記画素スペーサのパターンに沿って形成された画素開口部と、前記外周スペーサのパターンに沿って形成された外周開口部とを有し、２００ｎｍ〜５００ｎｍの範囲内の波長を４０％以上吸収するフィルターが、少なくとも前記外周開口部に配置されているマスクを用い、前記マスクを介して、前記感光層を露光する露光工程と、
前記露光された感光層を現像することにより、前記ブラックマトリクスが形成されている領域の保護層上に形成され、モノクロ液晶ディスプレイの表示領域である画素部に位置する画素スペーサと、液晶ディスプレイの表示領域外である外周部に位置する外周スペーサとからなる柱状スペーサを形成する柱状スペーサ形成工程とを有することを特徴とするものである。
【００７８】
本発明においては、上述した範囲内の波長を上記範囲で吸収する性質を有するフィルターを、少なくともマスクの外周開口部に配していることから、同一材料を用いて高さの異なる画素スペーサおよび外周スペーサを同時に形成することが可能である。これにより外周部および画素部におけるブラックマトリクスの線幅の違いを要因として生じる保護層の外周部および画素部における膜厚の差による影響を回避することができ、最終的に得られるモノクロ液晶ディスプレイ用基板において、基板表面から外周スペーサ上端面までの高さと、基板表面から画素スペーサ上端面までの高さとの差を好適な範囲内に調整することができる。従って、このようなモノクロ液晶ディスプレイ用基板上に対向基板を配置させると、対向基板が外周部に向って間隙が広がるようにゆがむことが防止され、対向基板の周辺から光が漏れるといった不都合が生じにくくなる。これにより、モノクロ液晶ディスプレイにおいて画面周辺が不自然に明るくなるといった問題を解決することができる。
【００７９】
以下、本発明のモノクロ表示装置用基板について図面を用いて説明する。図２は、本発明のモノクロ表示装置用基板の製造方法の一例を示した工程図である。
【００８０】
まず、図２（ａ）に示すように、モノクロ液晶装置用基板の透明基板３０上に、画素間を区分するブラックマトリクス１２をパターン状に形成する。ブラックマトリクス１２は、モノクロ液晶ディスプレイの表示領域である画素部Ａに形成された画素ブラックマトリクス１２ａと、表示領域外である外周部Ｂに形成された外周ブラックマトリクス１２ｂとからなり、両者は線幅が異なるように形成される。具体的に画素ブラックマトリクス１２ａは、表示領域の開口率の低下を防止するために線幅が狭く形成され、一方、外周ブラックマトリクス１２ｂは、光源からの光を遮蔽するために、線幅が広く形成する。
【００８１】
次に、このようなブラックマトリクス１２が形成されているモノクロ液晶ディスプレイ用基板の透明基板３０上に、図２（ｂ）に示すようにブラックマトリクス１２等の部材を保護し、透明基板３０表面に平坦性を付与するために、ブラックマトリクス１２表面を覆うように保護層１３を形成する。このような保護層１３においては、画素ブラックマトリクス１２ａと外周ブラックマトリクス１２ｂとにおける線幅の違いを要因として、各ブラックマトリクス１２上での膜厚に差が生じる。すなわち、画素ブラックマトリクス１２ａは線幅が狭いため、そのような画素ブラックマトリクス１２ａ上面に積層される保護層１３の膜厚は薄くなる傾向にある。一方、外周ブラックマトリクス１２ｂは、保護層１３が積層されるのに十分な線幅を有して形成されているため、その上面に積層される保護層１３の膜厚は画素ブラックマトリクス１２ａ上面の保護層１３の膜厚よりも厚くなるからである。
【００８２】
さらに、図２（ｃ）に示すように、感光層１４を保護層１３上に成膜する。次に、感光層１４をパターニングする際に使用するマスク１６を準備する。当該マスク１６は、遮光層１７と、画素スペーサを形成する位置に該当する画素開口部１８ａと、外周スペーサを形成する位置に該当する外周開口部１８ｂとを有している。さらに、当該外周開口部１８ｂには、所定の範囲内の波長を所定の割合吸収する性質を有するフィルター１９が配置されている。このようなマスク１６を介して、図２（ｄ）に示すように、感光層１４をパターン露光する。本発明においては、マスク１６の外周開口部１８ｂにフィルター１９を配していることから、外周開口部１８ｂに該当する部分の感光層１４は、フィルター１９により所定の範囲内の波長が所定の割合吸収された光が露光されるため、画素開口部１８ａに該当する部分の感光層１４よりも硬化が緩やかに進行する。
【００８３】
そして、パターン露光された感光層１４を現像・洗浄すると、図２（ｅ）に示すように、マスク１６の遮光層１７により未露光領域となった部分の感光層１４は除去され、画素開口部１８ａおよび外周開口部１８ｂにより露光領域となった部分の感光層１４が残存する。これにより、ブラックマトリクス１２が形成されている領域の保護層１３上に、画素部Ａに位置する画素スペーサ２０ａと、外周部Ｂに位置する外周スペーサ２０ｂとが形成される。さらに、本発明においては、外周開口部１８ｂにのみ、所定の範囲内の波長を所定の割合吸収する性質を有するフィルター１９を配してパターン露光を行っていることから、外周スペーサ２０ｂの方が画素スペーサ２０ａよりも膜厚が薄く形成される。これにより、保護層１３の画素部Ａおよび外周部Ｂにおける膜厚の差による影響を解消することができるモノクロ液晶ディスプレイ用基板を得る。
【００８４】
最後に、図２（ｆ）に示すように、対向基板２１をこのようなモノクロ液晶ディスプレイ用基板に張り合わせると、本発明においては、透明基板３０表面から画素スペーサ２０ａの上端面までの高さと、透明基板３０表面から外周スペーサ２０ｂの上端面までの高さとが良好な均一性を持ったモノクロ液晶ディスプレイ用基板とすることができるため、対向基板２１に不都合なゆがみが生じることがなく、光源からの光が対向基板２１周辺等から漏れるおそれがないため、表示画面の周辺が不自然に明るくなるといった問題を解消することができる。
【００８５】
なお、ここでいう「画素部」とは、本発明のモノクロ液晶ディスプレイ用基板を用いてモノクロ液晶ディスプレイとした際に、実際にモノクロ表示が行われる表示領域となる部分を意味する。さらに、「外周部」とは、当該画素部の周囲に位置し、前述した表示領域外に該当する部分を意味する。
【００８６】
以下、このような利点を有する本発明のモノクロ表示装置用基板の製造方法について各工程毎に説明する。
【００８７】
１．基板準備工程
まず、基板準備工程について説明する。本発明における基板準備工程とは、パターン状に形成されたブラックマトリクスと、前記パターン状に形成されたブラックマトリクスを被覆するように形成された保護層とを有する基板を準備する工程である。
【００８８】
以下、ブラックマトリクス、保護層および基板について説明する。
【００８９】
（１）ブラックマトリクス
本発明において用いられるブラックマトリックスとは、液晶分子の配向に応じてモノクロ表示が行われる画素を区分するために設けられるものである。このようなブラックマトリックスを製造する方法は、特に限定されるものではなく、例えばスパッタリング法、真空蒸着法等により、厚み１０００Å〜２０００Å程度のクロム等の金属薄膜を形成し、この薄膜をパターニングすることにより形成する方法等を挙げることができる。
【００９０】
このようなブラックマトリクスにおいて画素部では、表示領域の開口率を高めるために線幅を狭く形成する。一方、外周部では、バックライト等の光源からの光を効果的に遮蔽するため、画素部のブラックマトリクスよりも幅広に設けられる。具体的に画素部に設けられるブラックマトリクスの線幅は、一般的に、６μｍ〜２０μｍの範囲内であり、一方、外周部におけるブラックマトリクスの線幅は、２ｍｍ〜１０ｍｍの範囲内である。
【００９１】
また、上記ブラックマトリックスとしては、樹脂バインダ中にカーボン微粒子、金属酸化物、無機顔料、有機顔料等の遮光性粒子を含有させてもよく、用いられる樹脂バインダとしては、ポリイミド樹脂、アクリル樹脂、エポキシ樹脂、ポリアクリルアミド、ポリビニルアルコール、ゼラチン、カゼイン、セルロース等の樹脂を１種または２種以上混合したものや、感光性樹脂、さらにはＯ／Ｗエマルジョン型の樹脂組成物、例えば、反応性シリコーンをエマルジョン化したもの等を用いることができる。このような樹脂性ブラックマトリックスのパターニングの方法は、フォトリソ法、印刷法等一般的に用いられている方法を用いることができる。
【００９２】
（２）保護層
本発明における保護層とは、上述したブラックマトリクス等が形成された基板において、これらの部材を保護し、かつモノクロ液晶ディスプレイ用基板の基板表面に平坦性を付与するために設けられるものである。
【００９３】
このような保護層を形成する材料としては、アクリル樹脂、エチレン−酢酸ビニル共重合体、エチレン−塩化ビニル共重合体、エチレンビニル共重合体、ポリスチレン、アクリロニトリル−スチレン共重合体、ＡＢＳ樹脂、ポリメタクリル酸樹脂、エチレンメタクリル酸樹脂、ポリ塩化ビニル樹脂、塩素化塩化ビニル、ポリビニルアルコール、セルロースアセテートプロピオネート、セルロースアセテートブチレート、ナイロン６、ナイロン６６、ナイロン１２、ポリエチレンテレフタレート、ポリブチレンテレフタレート、ポリカーボネート、ポリビニルアセタール、ポリエーテルエーテルケトン、ポリエーテルサルフォン、ポリフェニレンサルファイド、ポリアリレート、ポリビニルブチラール、エポキシ樹脂、フェノキシ樹脂、ポリイミド樹脂、ポリアミドイミド樹脂、ポリアミック酸樹脂、ポリエーテルイミド樹脂、フェノール樹脂、ユリア樹脂等、および、重合可能なモノマーであるメチルアクリレート、メチルメタクリレート、エチルアクリレート、エチルメタクリレート、ｎ−プロピルアクリレート、ｎ−プロピルメタクリレート、イソプロピルアクリレート、イソプロピルメタクリレート、ｓｅｃ−ブチルアクリレート、ｓｅｃ−ブチルメタクリレート、イソブチルアクリレート、イソブチルメタクリレート、ｔｅｒｔ−ブチルアクリレート、ｔｅｒｔ−ブチルメタクリレート、ｎ−ペンチルアクリレート、ｎ−ペンチルメタクリレート、ｎ−ヘキシルアクリレート、ｎ−ヘキシルメタクリレート、２−エチルヘキシルアクリレート、２−エチルヘキシルメタクリレート、ｎ−オクチルアクリレート、ｎ−オクチルメタクリレート、ｎ−デシルアクリレート、ｎ−デシルメタクリレート、スチレン、α−メチルスチレン、Ｎ−ビニル−２−ピロリドン、グリシジル（メタ）アクリレートの一種以上と、アクリル酸、メタクリル酸、アクリル酸の２量体（例えば東亜合成化学（株）製Ｍ−５６００）、イタコン酸、クロトン酸、マレイン酸、フマル酸、ビニル酢酸、これらの酸無水物等の一種以上からなるポリマーまたはコポリマー等を１種若しくは２種以上含む感光性樹脂組成物が挙げられる。その中でも、保護層として要求される平坦性の観点からアクリル樹脂を用いた感光性樹脂組成物であることが好ましい。
【００９４】
また、保護層の膜厚としては、基板上に平坦性を付与することが可能な膜厚であれば特に限定はされないが、具体的には、０．３μｍ〜１０μｍの範囲内、その中でも、０．７μｍ〜２μｍの範囲内であることが好ましい。
【００９５】
このような保護層を形成する方法としては、公知の塗布方法により形成することが可能でありスピンコーティング法、キャスティング法、ディッピング法、バーコート法、ブレードコート法、ロールコート法、グラビアコート法、フレキソ印刷法、スプレーコート法等の塗布方法を挙げることができる。
【００９６】
なお、ブラックマトリクス上に積層された保護層の画素部および外周部における膜厚の差は、実際に形成されたブラックマトリクスの両方の部分における線幅の違いや、保護層を形成する材料によって異なるものであるため一概に規定することは困難であるが、一般的には、０μｍ〜０．５μｍの範囲内であることが多い。
【００９７】
（３）基板
本発明におけるモノクロ液晶ディスプレイ用基板の基板は、他の構成部材を実装するためのものであり、このような基板としては、例えばガラス基板、ガラスフィルム、合成樹脂基板、合成樹脂フィルム等を用いることができ、透光性に優れたものであることが好ましい。
【００９８】
２．感光層形成工程
次に、感光層形成工程について説明する。本発明における感光層形成工程とは、光硬化型樹脂組成物を上記基板上に塗布し、感光層を形成する工程である。具体的には、図２（ｃ）に示すように、パターン状に形成されたブラックマトリクス１２と、当該ブラックマトリクス１２を覆うように透明基板３０上に形成された保護層１３とを有する透明基板３０において、当該保護層１３上に、光硬化型樹脂組成物を塗布し、感光層１４を形成する工程である。
【００９９】
本工程により成膜される感光層は、後述する柱状スペーサ形成工程においてパターン状に形成されることにより、モノクロ液晶ディスプレイ用基板と対向基板との間隙を一定に保持する画素スペーサおよび外周スペーサとなる層である。また、本発明においては、上述した高低パターン層形成体の製造方法を用いて、当該感光層をパターニングしているため、高さの異なる画素スペーサおよび外周スペーサを、同一材料を用いて同時に形成することができる。
【０１００】
その他、本工程に関することは、上述した「Ａ．高低パターン層形成体の製造方法、１．感光層形成工程」の中に記載したものと同様であるのでここでの説明は省略する。
【０１０１】
３．露光工程
次に露光工程について説明する。本発明における露光工程とは、光の透過を遮る遮光層と、前記画素スペーサのパターンに沿って形成された画素開口部と、前記外周スペーサのパターンに沿って形成された外周開口部とを有し、２００ｎｍ〜５００ｎｍの範囲内、好ましくは、３００ｎｍ〜４５０ｎｍの範囲内の波長を４０％以上吸収するフィルターが、少なくとも前記外周開口部に配置されているマスクを用い、前記マスクを介して、上記感光層を露光する工程である。
【０１０２】
なお、ここでいう外周開口部とは、外周スペーサのパターンに沿って遮光層が除去されている部分を意味する。外周スペーサは、外周部に位置する柱状スペーサであるため、外周開口部もマスクの外周部に該当する部分に形成されている。さらに、ここでいう画素開口部とは、画素スペーサのパターンに沿って遮光層が除去されている部分を意味する。画素スペーサは、画素部に位置する柱状スペーサであるため、画素開口部もマスクの画素部に該当する部分に形成されている。
【０１０３】
本発明においては、ブラックマトリクスの外周部および画素部における線幅の違いを要因として生じる保護層の外周部および画素部における膜厚の差を、高さの異なる外周スペーサおよび画素スペーサを設けることで解消するものである。すなわち保護層の膜厚は、画素部よりも外周部において厚くなる傾向があるため、このような保護層の膜厚の差を解消するためには、外周スペーサを画素スペーサよりも高さを低く形成する必要がある。
【０１０４】
そこで、本発明においては、上述した高低パターン層において、低部を外周スペーサとし、高部を画素スペーサとするため、外周スペーサのパターンに形成されたマスクの外周開口部に上述したフィルターを配置している。これにより、感光層の外周スペーサとなり得る部分は、フィルターを通過した光が露光されるため、フィルターを介さずに露光される感光層の画素スペーサとなり得る部分よりも、硬化が緩やかに進行し、後述する柱状スペーサ形成工程において、現像後の残膜率が低くくなる。
【０１０５】
その他、本工程に関することは上述した「Ａ．高低パターン層形成体の製造方法、２．露光工程」の中に記載したことと同様であるのでここでの説明は省略する。
【０１０６】
４．柱状スペーサ形成工程
最後に柱状スペーサ形成工程について説明する。本発明における柱状スペーサ形成工程とは、上述した露光された感光層を現像することにより、前記ブラックマトリクスが形成されている領域の保護層上に、モノクロ液晶ディスプレイの表示領域である画素部に位置する画素スペーサと、モノクロ液晶ディスプレイの表示領域外である外周部に位置する外周スペーサとからなる柱状スペーサを形成する工程である。
【０１０７】
（柱状スペーサ）
本発明における柱状スペーサとは、内部に液晶層を挟持する２枚の基板間に配され、当該２枚の基板間の間隙を一定に保持するために設けられるものである。このような柱状スペーサにおいて、本発明では、モノクロ液晶ディスプレイの表示領域に該当する画素部に配置された柱状スペーサを画素スペーサとし、表示領域外に該当する外周部に配置された柱状スペーサを外周スペーサとしている。
【０１０８】
本発明においては、このような画素スペーサおよび外周スペーサを高さの異なるように、同一材料を用いて同時にフォトリソグラフィー法により形成することが可能である。
【０１０９】
すなわち、上述した露光工程において、少なくとも外周開口部に、所定の範囲内の波長を所定の範囲で吸収する性質を有するフィルターが配置されているマスクを使用しているので、フィルターの有無で光硬化型樹脂組成物の硬化の度合いに違いを生じさせることができる。これにより、画素スペーサの方が外周スペーサよりも膜厚を厚く形成することが可能である。
【０１１０】
また、画素スペーサおよび外周スペーサの各々の高さの関係は、対抗基板がモノクロ液晶ディスプレイ用基板に張り合わされた際に２つの基板間に不都合なゆがみが生じない程度に、画素スペーサの高さが外周スペーサの高さよりも高ければ特に限定はされない。ブラックマトリクスの画素部および外周部における幅の違いから、保護層の膜厚は外周部よりも画素部の方が薄く形成されるからであり、このように画素スペーサの高さを外周スペーサの高さよりも高くすることによりそのような保護層の膜厚の差を、柱状スペーサにより是正することができるからである。
【０１１１】
具体的に画素スペーサおよび外周スペーサの高さの差は、ブラックマトリクス上に成膜された保護層の画素部と外周部とにおける膜厚の差に応じて調整される。例えば、保護層が成膜された段階で、保護層の膜厚の差を計測し、またはシュミレーション等することにより、モノクロ液晶ディスプレイ用基板の状態を把握し、その状態に応じて画素スペーサおよび外周スペーサの高さの差を調整する。さらに、画素スペーサおよび外周スペーサの高さの差を、所望の差とするためには、フィルターおよび露光量の変化に応じた感光層の残膜率を実験により計測しておくことにより、モノクロ液晶ディスプレイ用基板の状態に適したフィルターおよび露光量等を決定することにより可能となる。
【０１１２】
また画素スペーサおよび外周スペーサの高さの差は、保護層の外周部および画素部における膜厚の差に応じて調整されるため、一概に規定することは困難であるが、一般的に生じ得る保護層の膜厚の差をもとに規定すると、画素スペーサ自体の高さが外周スペーサ自体の高さよりも、０μｍ〜１．３μｍの範囲内で高いことが好ましく、その中でも０．５μｍ〜１．１μｍの範囲内で高く形成されていることが好ましい。上記範囲内の高さの差を有して画素スペーサおよび外周スペーサを形成できれば、モノクロ液晶ディスプレイ用基板の基板表面から画素スペーサ上面までの高さを、同様の基板表面から当該基板の外周スペーサ上面までの高さよりも０μｍ〜０．８μｍの範囲内で高くすることができるため、対向基板に不都合なゆがみを発生させることなく、２枚の基板を高度に均一な間隙を保持して配置させることができるからである。
【０１１３】
また、画素スペーサ自体の高さは、一般的なモノクロ液晶ディスプレイにおいて用いられている高さであれば特に限定はされず、具体的には、２．５μｍ〜５．５μｍの範囲内であることが好ましい。
【０１１４】
さらに、本発明における柱状スペーサの形状としては、２枚の基板間の間隙を一定に保つことを可能とする形状であれば特に限定はされない。具体的には、円柱形状、角柱形状または截頭錐体形状等を挙げることができる。
【０１１５】
Ｃ．ＭＶＡモード液晶ディスプレイの製造方法
次に、ＭＶＡモード液晶ディスプレイの製造方法について説明する。本発明のＭＶＡモード液晶ディスプレイの製造方法は、上述した高低パターン層形成体の製造方法を用いたＭＶＡモード液晶ディスプレイの製造方法であって、
前記高低パターン層が、前記ＭＶＡモード液晶ディスプレイに用いられる配向制御突起およびＭＶＡ用柱状スペーサであり、
前記マスクが、光の透過を遮る遮光層と、前記配向制御突起のパターンに沿って形成された第１開口部と、前記ＭＶＡ用柱状スペーサのパターンに沿って形成された第２開口部とを有し、少なくとも前記第１開口部に、前記フィルターが配置されていることを特徴とするものである。
【０１１６】
本発明においては、ＭＶＡモード液晶ディスプレイに用いられる配向制御突起およびＭＶＡ用柱状スペーサをフォトリソグラフィー法により同一の材料を用いて同時に製造することができる。
【０１１７】
このような利点を有する本発明のＭＶＡモード液晶ディスプレイモード液晶ディスプレイの製造方法について図面を用いて具体的に説明する。
【０１１８】
図３は、本発明のＭＶＡモード液晶ディスプレイの製造方法の一例を示した工程図である。まず、図３（ａ）に示すように、透明基板３１上に、光硬化型樹脂組成物を塗布し、感光層３２を形成する。次に、図３（ｂ）に示すように、光の透過を遮る遮光層３３と、配向制御突起のパターンに沿って形成された第１開口部３４ａと、ＭＶＡ用柱状スペーサのパターンに沿って形成された第２開口部３４ｂとを有し、前記第１開口部３４ａに、所定の範囲内の波長を所定の範囲吸収する性質を有するフィルター３５が配置されているマスク３６を準備する。当該マスク３６を介して、前記感光層３２に露光する。これにより、第１開口部３４ａと第２開口部３４ｂとで、フィルター３５の有無によるパターンを感光層３２に形成することができる。次いで、露光された感光層３２を現像・洗浄することにより、図３（ｃ）に示すように、遮光層３３により光の透過が遮られた未露光領域の感光層３２は除去されるが、第１開口部３４ａおよび第２開口部３４ｂにより露光領域となった部分の感光層３２は残存する。さらに、本発明においては、第１開口部３４ａにはフィルター３５を配置していることから、同様に露光領域であっても、第１開口部３４ａに該当する部分の露光領域は、第２開口部３４ｂに該当する部分の露光領域よりも、硬化の度合いが低く、従って、図３（ｃ）に示すように、第１開口部３４ａに該当する露光領域が配向制御突起３７となり、第２開口部３４ｂに該当する露光領域がＭＶＡ用柱状スペーサ３８となる。かつ、配向制御突起の方がＭＶＡ用柱状スペーサよりも膜厚が薄く形成される。
【０１１９】
以下、本発明のＭＶＡモード液晶ディスプレイの製造方法について各工程毎に分けて説明する。
【０１２０】
１．感光層形成工程
本発明における感光層形成工程とは、基板上に、光硬化型樹脂組成物を塗布し、感光層を形成する工程である。
【０１２１】
本工程は、上述した「Ａ．高低パターン層形成体の製造方法、１．感光層形成工程」と同様であるためここでの説明は省略する。
【０１２２】
２．露光工程
次に、本発明における露光工程とは、光の透過を遮る遮光層と、配向制御突起のパターンに沿って形成された第１開口部と、ＭＶＡ用柱状スペーサのパターンに沿って形成された第２開口部とを有し、２００ｎｍ〜５００ｎｍの範囲内の波長を４０％以上吸収するフィルターが、少なくとも前記第１開口部に配置されているマスクを用い、前記マスクを介して、感光層を露光する工程である。
【０１２３】
なお、ここでいう第１開口部とは、配向制御突起のパターンに沿って、遮光層が除去された部分を意味する。さらに、ここでいう第２開口部とは、ＭＶＡ用柱状スペーサのパターンに沿って遮光層が除去された部分を意味する。
【０１２４】
本発明においては、上述した高低パターン層において、低部が配向制御突起となり、高部がＭＶＡ用柱状スペーサとなるように、配向制御突起のパターンに形成されたマスクの第１開口部に上述したフィルターを配置している。これにより、感光層の配向制御突起となり得る部分は、フィルターを通過した光が露光されるため、フィルターを介さずに露光される感光層のＭＶＡ用柱状スペーサとなり得る部分よりも、硬化が緩やかに進行し、後述するＭＶＡ用柱状スペーサ形成工程において、現像後の残膜率が低くくなるのである。
【０１２５】
その他、本工程に関することは上述した「Ａ．高低パターン層形成体の製造方法、２．露光工程」の中に記載したことと同様であるのでここでの説明は省略する。
【０１２６】
３．配向制御突起およびＭＶＡ用柱状スペーサ形成工程
最後に配向制御突起およびＭＶＡ用柱状スペーサ形成工程について説明する。本発明における配向制御突起およびＭＶＡ用柱状スペーサ形成工程とは、上述した露光工程により、露光された感光層を現像することにより、配向制御突起およびＭＶＡ用柱状スペーサを形成する工程である。
【０１２７】
本工程において、形成される配向制御突起およびＭＶＡ用柱状スペーサについて説明する。
【０１２８】
（１）配向制御突起
本発明における配向制御突起とは、液晶層の配向を制御する突起を意味する。このような配向制御突起に接触する液晶分子は、配向制御突起との接触面に対して垂直方向に配向するため、液晶層に電圧を印加した際に、この突起近傍の傾斜した液晶分子を起点として、各液晶分子を所定の方向に配向させることが可能となる。これにより、配向制御突起の頂点を境に液晶の配向方向を、水平方向に見て１８０度、鉛直方向には傾斜した角度で、対称的に配向させることができる。そして、隣接する２つの領域を１組とし、さらにこの組み合わせを複数組み合わせて１画素を表示することで、観測者の見る角度を配向制御突起の垂直方向に変化させても、観測者は常に同じ像を見ることが可能となる。すなわち、広い視野角を確保することができる。なお、配向制御突起は、直線状（特にジグザグ線状）であるのが好ましいがこれに限定されず、点線状等であってもよい。
【０１２９】
本発明においては、このような配向制御突起を後述するＭＶＡ用柱状スペーサと同一材料を用いて、かつ、ＭＶＡ用柱状スペーサの方が、配向制御突起よりも膜厚が高くなるように同時に製造することを特徴とするものである。
【０１３０】
このような配向制御突起の高さは、後述するＭＶＡ用柱状スペーサより低いのであれば特に限定されないが、０．５〜２μｍとすることが好ましい。
【０１３１】
さらに、本発明においては、このような配向制御突起が所定間隔毎に９０度屈折してなるジグザグ線状に設けられてなり、各ジグザグ線が互いに平行なストライプ状に形成されていることが好ましい。これにより、配向制御突起線の垂直方向のみならず、上下左右の全方向において完全に対称な視野角特性を得ることができるからである。すなわち、配向制御突起線の９０度の屈折角を境に隣接した２つの領域間で、水平方向に１８０度の対称性を有している液晶分子の配向が、９０度異なっている。このため、屈折角および配向制御突起を境に４つの領域に分割されることになり、これら４つの領域間で、液晶分子の長軸の配向角度が、ジグザグ線の中心軸に対し、水平方向に４５度の角度で、鉛直方向には傾斜した角度で、４方向に配向する。このようにして、１つの画素を互いに対称な角度で４分割して表示することができるので、観測者は上下左右の全方向において常に同じ像を見ることが可能となる。
【０１３２】
（２）ＭＶＡ用柱状スペーサ
次に、ＭＶＡ用柱状スペーサについて説明する。本発明におけるＭＶＡ用柱状スペーサとは、２枚の基板間に狭持された液晶層の間隔を均一に保持して、液晶層の厚さを規定するために設けられている。
【０１３３】
本発明においては、このようなＭＶＡ用柱状スペーサが、上述した配向制御突起と同時に、同一材料を用いて、かつ当該ＭＶＡ用柱状スペーサの方が配向制御突起よりも膜厚が厚くなるように、フォトリソグラフィー法により製造されることを特徴とする。
【０１３４】
このようなＭＶＡ用柱状スペーサは、液晶ディスプレイの輝度に悪影響を及ぼすことがない位置であればいかなる位置であっても限定はされないが、配向制御突起と重なる位置に設けられることが好ましい。これにより、液晶ディスプレイの輝度を低減することなく、ＭＶＡ用柱状スペーサの大きさの選択の範囲を広げることができるからである。なお、ＭＶＡ用柱状スペーサは、配向制御突起と重なる位置であれば、配向制御突起から多少はみ出していてもよいし、配向制御突起よりも狭く設けてもよい。また、配向制御突起をジクザク状に形成した場合には、ジクザク状の屈折部分に設けてもよいし、屈折部以外の直線部分に設けてもよく、特に限定されない。また、ＭＶＡ用柱状スペーサおよび上述した配向制御突起は、着色されたものであってもよいし、透明であってもよく、特に限定はされない。
【０１３５】
ＭＶＡ用柱状スペーサを配向制御突起と重なるように設けた場合には、そのような配向制御突起と重なる部分の中でも、ＭＶＡ用柱状スペーサがジグザグ線の屈折部（頂点）に一致するように設けられることが好ましい。電圧印加時において、屈折部を結ぶ線上においては、２方向から倒れた液晶分子が迫り合ってしまうので、垂直に近い配向方向を有し、透光性が著しく低下する。このため、屈折部を結ぶ線の近傍は常に暗くなっており、そのような位置にＭＶＡ用柱状スペーサを配置することで、両者により及ぼされる不都合を一箇所に統合することがでできるからである。すなわち配向制御突起上にＭＶＡ用柱状スペーサを形成することにより、液晶の配向にいかなる影響をも与えないこととすることができる。また、配向制御突起が透明な材料で形成されている場合には、配向制御突起上であっても屈折部以外にスペーサを形成すると、白表示時にＭＶＡ用柱状スペーサが黒点として観察されてしまうおそれがあるが、屈折部上にＭＶＡ用柱状スペーサを形成することでこのような不都合を防止できるという利点もある。
【０１３６】
このようなＭＶＡ用柱状スペーサの高さとしては、１〜１０μｍの範囲内であることが好ましくは、その中でも、２〜１０μｍの範囲内、さらには、１〜８μｍの範囲内であることが好ましい。
【０１３７】
なお、本発明は、上記実施形態に限定されるものではない。上記実施形態は例示であり、本発明の特許請求の範囲に記載された技術的思想と実質的に同一な構成を有し、同様な作用効果を奏するものは、いかなるものであっても本発明の技術的範囲に包含される。
【０１３８】
【実施例】
以下に実施例を示し、本発明をさらに説明する。
【０１３９】
［実施例］
基板上に高低パターン層形成用材料としてＪＣＲ（株）製オプトマーＮＮシリーズを用いスピンコート法により５μｍの膜を成膜した。この膜を１００μｍの間隙を介して２００ｎｍ〜５００ｎｍの範囲内の波長を１０％、４０％透過する性質を有するフィルターを有するフォトマスクを用いて２０〜１００ｍＪ／ｃｍで露光した。これを０．０５ｗｔ％ＫＯＨ水溶液で６０秒現像した。その後、２３０℃で３０秒間焼成することにより図５のような高さの異なる高部および低部からなる高低パターン層を同一材料を用いて同時に形成できた。
【０１４０】
【発明の効果】
本発明によれば、２００ｎｍ〜５００ｎｍの範囲内の波長を４０％以上吸収する性質を有するフィルターを開口部の一部に配置していることから、露光工程において露光領域となった感光層であってもフィルターの有無により、現像後の残膜率に違いを生じさせることができる。従って、高さの異なる高部および低部からなる高低パターン層を、同一材料を用いて、同時に形成することができるといった効果を奏する。
【図面の簡単な説明】
【図１】本発明の高低パターン層の製造方法の一例を示す工程図である。
【図２】本発明のモノクロ液晶ディスプレイ用基板の製造方法の一例を示す工程図である。
【図３】本発明のＭＶＡモード液晶ディスプレイの製造方法の一例を示す工程図である。
【図４】従来におけるモノクロ液晶ディスプレイ用基板の一例を示す工程図である。
【図５】フィルターを介さずに露光した場合および光の透過率の異なる２種類のフィルターを用いた場合における、感光層の露光量の変化に伴う現像後の膜厚を示したグラフである。
【符号の説明】
１ … 基板
２ … 感光層
３ … 遮光層
４ … 開口部
５ … フィルター
６ … マスク
７、８ … 露光領域
９ …未露光領域
１０ … 低部
１１ … 高部[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for manufacturing a high / low pattern layer.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, liquid crystal displays have been used as information display means in various fields, regardless of whether they are monochrome or color.
[0003]
For example, a monochrome liquid crystal display includes a substrate, a black matrix formed in a pattern on the substrate, and a protective layer provided for protecting the black matrix and ensuring flatness of the substrate surface. The structure has at least a display substrate, a counter substrate facing the monochrome liquid crystal display substrate, and a liquid crystal layer sandwiched between the monochrome liquid crystal display substrate and the counter substrate.
[0004]
In recent years, a columnar spacer has been used as a spacer (spacer) for maintaining a constant gap between a monochrome liquid crystal display substrate and a counter substrate in place of a conventionally used plastic bead. That is, a columnar spacer is formed on one of the substrates to eliminate a reduction in contrast due to light leakage around the plastic beads and display unevenness due to uneven scattering, and the spacer is used to form a gap between the two substrates. Keeping constant is done.
[0005]
As shown in FIG. 4, an example of a conventional substrate for a monochrome liquid crystal display using such a columnar spacer is a black matrix 42 that separates pixels in a pattern on a substrate 41 of the substrate for a monochrome liquid crystal display as shown in FIG. Is formed. Such a black matrix 42 has a pixel black matrix 42a formed in a pixel portion A which is a display region of a monochrome liquid crystal display, and an outer peripheral black matrix 42b formed in an outer peripheral portion B which is outside the display region. The pixel black matrix 42a has a narrow line width so as not to lower the aperture ratio of the display area, and the outer black matrix 42b effectively blocks light from a light source such as a backlight. Therefore, the line width is formed wide.
[0006]
Further, a protective layer 43 is formed so as to cover the surface of the black matrix 42 in order to protect members such as the black matrix 42 and impart flatness to the surface of the substrate 41 of the monochrome liquid crystal display substrate. In such a protective layer 43, there is a difference in thickness between the pixel portion A and the outer peripheral portion B. This is because the pixel black matrix 42a located in the pixel portion A is formed with a small line width, so that the protective layer 43 is difficult to be laminated on the upper surface thereof, and the thickness of the laminated protective layer 43 tends to be small. On the other hand, since the outer peripheral black matrix 42b provided in the outer peripheral portion B is formed with a sufficient line width, the thickness of the protective layer 43 is larger than that of the pixel portion A. Because it becomes. When the columnar spacers 44 are formed on such a protective layer 43, the height from the surface of the substrate 41 of the monochrome liquid crystal display substrate to the upper surface of the columnar spacers 44 is increased due to the difference in the thickness of the protective layer 43 itself. , The outer peripheral portion B is higher than the pixel portion A.
[0007]
Such a difference in height appears as a difference in the gap between the substrates. In such a state, when the counter substrate 45 is disposed on the monochrome liquid crystal display substrate via the columnar spacers 44, the counter substrate 45 is formed. Distortion occurs. The distortion causes an inconvenience that light leaks from a peripheral portion of the counter substrate 45, thereby causing a problem that the periphery of the screen becomes bright.
[0008]
Therefore, as a method for solving such a problem, for example, Japanese Patent Application Laid-Open No. H11-163873 discloses a method for preventing the height of the columnar spacer itself from being varied outside the display region and the display region of the liquid crystal display device. There is disclosed a technique using a columnar spacer composed of a large-diameter spacer and a small-diameter spacer composed of two or more layers. Further, Patent Document 2 discloses that, in order to prevent the columnar spacer from changing due to the influence of high temperature and high pressure during the assembly of the liquid crystal display device, the columnar spacer is formed of a low deformation portion having a small deformation amount at high temperature and high pressure. A technique is disclosed in which the columnar spacer has a two-layer structure including a highly elastic portion capable of following the contraction of the liquid crystal at a low temperature to keep the shape of the columnar spacer constant.
[0009]
However, in any method, in order to form columnar spacers having different heights in the pixel portion A and the outer peripheral portion B, the height of the columnar spacers in the pixel portion and the outer peripheral portion is increased by repeating the process of forming the columnar spacer twice. Since the difference in height is eliminated, much effort is required to produce the columnar spacer, which is a factor that lowers the manufacturing efficiency.
[0010]
In addition, the MVA mode in a multi-alignment split type vertical alignment (hereinafter, the multi-alignment split type vertical alignment may be abbreviated as MVA) mode liquid crystal display is such that all liquid crystal molecules stand vertically on the alignment film when no voltage is applied. The display is controlled by the liquid crystal molecules falling down when a voltage is applied. Furthermore, in order to realize high-quality display, the direction in which the liquid crystal molecules fall is defined so as to be different for each adjacent domain, and a configuration is adopted in which a plurality of orientations are divided for each domain. This achieves a high viewing angle, high contrast, high-speed response, faithful color reproduction, high-definition display, and the like.
[0011]
In such an MVA mode liquid crystal display, rubbing with a cloth such as nylon or rayon has been performed in order to determine the orientation of liquid crystal molecules. However, when this method is used, the reliability in the production process is sufficient for reasons such as generation of static electricity due to the rubbing process, a decrease in yield due to dust generation, and a decrease in productivity due to a complicated process. I couldn't say. Further, when a spacer for defining the thickness of the liquid crystal layer is present, a portion that is shadowed by the spacer is not rubbed, and there is a disadvantage that the alignment of the liquid crystal molecules in that portion is disturbed.
[0012]
In view of such circumstances, in recent years, as described in Patent Document 3, a rubbing method has been used by providing a projection for controlling alignment (referred to as an alignment control projection in this specification) in a liquid crystal panel. Instead, a method of defining the tilt direction of liquid crystal molecules has been adopted. This is because the alignment control protrusions are provided in a zigzag line stripe shape such that the major axes of the liquid crystal molecules at the time of voltage application are all at an angle of 45 °, and the alignment direction in one pixel is divided into four, And it is designed so that the divided areas are equal. In this method, projections for controlling alignment are provided on both the color filter side substrate and the opposing substrate facing the color filter side substrate, and are formed so as to be alternately arranged when formed into cells.
[0013]
On the other hand, in general, in an MVA mode liquid crystal display provided with a projection for controlling alignment, spherical plastic beads are used as spacers for regulating the thickness of a liquid crystal layer. As in the case, a columnar spacer has been used to solve the problem when plastic beads are used.
[0014]
As described above, in the MVA mode liquid crystal display, it is beneficial to provide the alignment control projection and the columnar spacer. However, these are formed by the photolithography method using the same material. Due to the different sizes and patterns, they had to be formed separately. Therefore, there has been a demand for the development of a method capable of manufacturing both of them simultaneously using the same material.
[0015]
Therefore, Patent Document 3 discloses that (a) preparing a substrate having a negative photoresist applied to the outermost surface thereof, and (b) providing a plurality of predetermined cutout patterns on the surface having the photoresist applied thereon. Exposure is performed at a constant exposure amount through a photomask having an opening, and (c) the photomask is exposed such that the region exposed in the step (b) partially overlaps the next opening to be exposed. (D) the steps (b) and (c) are repeated a plurality of times in this order, and (e) the exposed substrate surface is developed with a developing solution. A method is disclosed in which a film is formed in accordance with the number of exposures, and the alignment control protrusions and the columnar spacers are made of the same material and simultaneously. However, this method has a drawback that the exposure step requires much time and effort because the thickness of the alignment control protrusion and the columnar spacer is varied depending on the number of exposures in the exposure step.
[0016]
[Patent Document 1]
JP-A-11-109366
[Patent Document 2]
JP-A-2002-148426
[Patent Document 3]
JP-A-2002-236371
[0017]
[Problems to be solved by the invention]
The present invention has been made in view of the above problems, and it is possible to easily manufacture a high / low pattern layer in which patterns having different heights are combined using the same material by photolithography and simultaneously. It is a main object of the present invention to provide a method for manufacturing a high-low pattern layer formed body.
[0018]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides, as set forth in claim 1, a substrate and a high / low pattern layer formed on the substrate and having a combination of patterns having different heights. A method for manufacturing a high-low pattern layer formed body in which the high-low pattern layer is manufactured simultaneously with the same material by a photolithography method,
Applying a photocurable resin composition on the substrate, a photosensitive layer forming step of forming a photosensitive layer,
A filter having a light-shielding layer that blocks light transmission and an opening formed along the pattern of the high / low pattern layer, and a filter that absorbs 40% or more of a wavelength in the range of 200 nm to 500 nm is provided in one of the openings. Using a mask arranged in the portion, through the mask, an exposure step of exposing the photosensitive layer,
Developing the exposed photosensitive layer to form a high / low pattern layer forming step of forming a high / low pattern layer in which a photosensitive layer corresponding to a region where a filter is disposed among the openings of the mask is a lower portion. A method for producing a high / low pattern layer forming body characterized by the above feature.
[0019]
In the present invention, since a filter having a property of absorbing the wavelength within the above-described range at the above-described ratio is disposed in a part of the opening, even if the photosensitive layer has become an exposure region in the exposure step, the filter may be used. Can cause a difference in the residual film ratio after the development. Therefore, the high and low pattern layers including the high portion and the low portion having different heights can be simultaneously formed using the same material.
[0020]
In the invention described in claim 1, as described in claim 2, it is preferable that the photocurable resin composition has different reactivity depending on the intensity of light within the range of 200 nm to 500 nm. By using a photocurable resin composition having different reactivity depending on the intensity of light having a wavelength in the same range as the wavelength range absorbed by the above-described filter, even in the photosensitive layer which has become an exposed region in the above-mentioned exposure step. The presence or absence of a filter can cause a difference in the degree of curing, so that a high-low pattern layer consisting of a high portion and a low portion having different heights can be easily formed using such a photocurable resin composition. This is because they can be formed simultaneously.
[0021]
In the first or second aspect of the present invention, as described in the third aspect, it is preferable that the high / low pattern layer forming body is used for a liquid crystal display substrate. In a liquid crystal display substrate, there are cases where two types of members having different heights are formed of the same material, and in such a case, by using the method for manufacturing a high / low pattern layer formed body of the present invention, it is possible to efficiently use the same. This is because a liquid crystal display substrate can be manufactured.
[0022]
In the present invention, as described in claim 4, a substrate for a monochrome liquid crystal display using the method for manufacturing a high / low pattern layer forming body according to any one of claims 1 to 3 is provided. Wherein the height pattern layer is a pixel spacer positioned in the display area of the monochrome liquid crystal display and an outer peripheral spacer positioned outside the display area of the monochrome liquid crystal display, and the mask is configured to transmit light. A light-blocking layer that blocks light, a pixel opening formed along the pattern of the pixel spacer, and an outer opening formed along the pattern of the outer spacer, and the filter is disposed at least in the outer opening. And a method for manufacturing a substrate for a monochrome liquid crystal display.
[0023]
In the present invention, since the pixel spacer and the outer peripheral spacer having different heights can be simultaneously formed using the same material by using the above-described method for manufacturing the high and low pattern layers, it is possible to efficiently form the columnar spacer. This is effective in improving the manufacturing efficiency of a substrate for a monochrome liquid crystal display device.
[0024]
Further, in the present invention, as described in claim 5, an MVA mode liquid crystal display using the method of manufacturing a high / low pattern layer forming body according to any one of claims 1 to 3 is provided. In the manufacturing method, the height pattern layer is an alignment control projection and an MVA columnar spacer used in the MVA mode liquid crystal display, and the mask is a light shielding layer that blocks light transmission, and a pattern of the alignment control projection. And a second opening formed along the pattern of the MVA columnar spacer, and the filter is arranged at least in the first opening. And a method for manufacturing an MVA mode liquid crystal display characterized by the following.
[0025]
In an MVA mode liquid crystal display, it is very useful to provide an alignment control projection and a columnar spacer for MVA. However, by forming them by the above-described method for manufacturing a high / low pattern layer forming body, the same material can be used at the same time. Therefore, the MVA mode liquid crystal display can be efficiently manufactured.
[0026]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a method for manufacturing a high / low pattern layer, a method for manufacturing a substrate for a monochrome liquid crystal display, and a method for manufacturing an MVA mode liquid crystal display according to the present invention will be described.
[0027]
A. Method for manufacturing high-low pattern layer formed body
First, a method for manufacturing a high / low pattern layer formed body will be described. The method for manufacturing a height pattern layer forming body of the present invention includes a substrate, a height pattern layer formed on the substrate, and a pattern having a different height is combined, wherein the height pattern layer is formed by a photolithography method. A method for manufacturing a high / low pattern layer formed body simultaneously manufactured with the same material,
Applying a photocurable resin composition on the substrate, a photosensitive layer forming step of forming a photosensitive layer,
A filter having a light-blocking layer that blocks light transmission and an opening formed along the pattern of the high / low pattern layer, and a filter that absorbs 40% or more of a wavelength in the range of 200 nm to 500 nm is provided at one of the openings. Using a mask arranged in the portion, through the mask, an exposure step of exposing the photosensitive layer,
Developing the exposed photosensitive layer to form a high / low pattern layer forming step of forming a high / low pattern layer in which a photosensitive layer corresponding to a region where a filter is disposed in the opening of the mask is a lower portion. It is characterized by the following.
[0028]
In the present invention, since a filter having a property of absorbing the wavelength within the above-described range at the above-described ratio is disposed in a part of the opening, even if the photosensitive layer has become an exposure region in the exposure step, the filter may be used. Can cause a difference in the residual film ratio after the development. Therefore, the high and low pattern layers including the high portion and the low portion having different heights can be simultaneously formed using the same material.
[0029]
The method for manufacturing the high / low pattern layer of the present invention having such advantages will be specifically described with reference to FIG.
[0030]
First, as shown in FIG. 1A, a photocurable resin composition is applied on a substrate 1 to form a photosensitive layer 2.
[0031]
Next, as shown in FIG. 1 (b), it has a light-shielding layer 3 that blocks light transmission and an opening 4 that is a light-transmitting region, and absorbs a wavelength within a predetermined range at a predetermined ratio. A filter 5 exposes the photosensitive layer 2 through a mask 6 provided in a part of the opening 4. At this time, the reactivity of the photocurable resin composition constituting the photosensitive layer 2 differs depending on the intensity of the wavelength on the short wavelength side of the light to be exposed. There is a difference in the degree of curing between the exposed region 8 and the portion exposed without the filter. In other words, the exposure region 7 exposed to light having a wavelength within a predetermined range absorbed by the filter 5 progresses more slowly than the exposure region 8 exposed to the light as it is.
[0032]
Thus, as shown in FIG. 1C, three types of patterns, that is, an exposed region 7 of a portion exposed through the filter 5, an exposed region 8 of a portion exposed without the filter, and an unexposed region 9 is formed on the photosensitive layer 2. When such a photosensitive layer 2 is developed and washed, as shown in FIG. 1D, the photosensitive layer 2 in the unexposed area 9 is removed, and the photosensitive layer 2 in the exposed area 7 and the exposed area 8 remains. Further, due to the difference in reactivity of the photocurable resin composition caused by the presence or absence of the filter 5, the exposed region 8 of the portion exposed without the filter is better than the exposed region 7 of the portion exposed through the filter 5. Also, the residual film ratio after development becomes high. As a result, the exposed region 7 of the portion exposed through the filter 5 forms a low portion 10, and the exposed region 8 exposed without passing through the filter forms a high portion 11. Therefore, the high / low pattern layer 12 including the high portion 11 and the low portion 10 can be simultaneously formed by the photolithography method using the same material.
[0033]
Hereinafter, the method of manufacturing the high / low pattern layer of the present invention will be described for each step.
[0034]
1. Photosensitive layer forming process
First, the photosensitive layer forming step will be described. The photosensitive layer forming step in the present invention is a step of applying a photocurable resin composition on a substrate to form a photosensitive layer.
[0035]
The photocurable resin composition used in the present invention is not particularly limited as long as it is a commonly used one, but particularly in the range of 200 nm to 500 nm, among them, depending on the intensity of light in the range of 300 nm to 450 nm. It is preferable that a difference occurs in reactivity.
[0036]
The difference in reactivity referred to here generally means that a difference occurs in a reaction that can occur when exposed to light in a photocurable resin composition. Since a high-low pattern layer formed body having a low-high pattern layer composed of a low portion is manufactured, it means a difference in reactivity that finally causes a change in the remaining film ratio of the photosensitive layer in the exposed area.
[0037]
Hereinafter, the photosensitive layer formed in this step will be described.
[0038]
(1) Photosensitive layer
The photosensitive layer in the invention is formed by applying a photocurable resin composition on a substrate. The photosensitive layer thus formed from the photocurable resin composition is cured by exposure. In the present invention, a filter that absorbs at least 40% of a wavelength in the range of 200 nm to 500 nm is used as a mask. Are arranged in a part of the opening, so that in an exposure step to be described later, two types of exposure areas, an area exposed through a filter and an area exposed without a filter, are formed. Become. In these exposure regions, since the wavelength of light to be exposed is different, the degree of curing is different. Therefore, by patterning such a photosensitive layer, a high-low pattern layer composed of high portions and low portions having different heights is formed. Can be formed.
[0039]
Hereinafter, the photocurable resin composition forming such a photosensitive layer will be described.
[0040]
(Photocurable resin composition)
The photocurable resin composition of the present invention is not particularly limited as long as it has a property of being cured by exposure, but among them, particularly, in the range of 200 nm to 500 nm, among them, the wavelength in the range of 300 nm to 450 nm. It is preferable that the difference in reactivity is caused by the intensity of light. Depending on the presence or absence of a filter that blocks light in the above-mentioned range used in the exposure step described below, a difference in the degree of curing can be caused, so that a high-low pattern layer composed of high portions and low portions having different heights easily. Can be formed at the same time.
[0041]
Such a photocurable resin composition is not particularly limited as long as it is a composition having a configuration utilizing i-line for curing. Specifically, Optmer NN series manufactured by JSR Corporation and Table 1 below The photosensitive resin composition of the composition example shown can be mentioned.
[0042]
[Table 1]

[0043]
The method of applying the photocurable resin composition is not particularly limited as long as it is a method of applying a coating liquid to the entire surface of the substrate. Specifically, a spin coating method, a casting method, a dipping method, and the like. Coating methods such as a bar coating method, a blade coating method, a roll coating method, a gravure coating method, a flexographic printing method, and a spray coating method are used.
[0044]
In the present invention, a photosensitive layer is formed by applying the above-described photocurable resin composition on a substrate using the above-mentioned application method.
[0045]
(2) Substrate
In this step, the above-mentioned photocurable resin composition is applied on a substrate. Such a substrate is not particularly limited as long as it is a material generally used as a substrate for various high-low pattern layer forming bodies, but a liquid crystal display substrate is used as the high-low pattern layer forming body in the present invention. Is preferable, it is preferable that the substrate has transparency. As a material of such a substrate, for example, a transparent rigid material having no flexibility such as quartz glass, Pyrex (registered trademark), or a synthetic quartz plate, or a material having flexibility such as a transparent resin film or an optical resin plate is used. A transparent flexible material or the like can be used.
[0046]
2. Exposure process
Next, the exposure step will be described. The exposure step in the present invention, a light-shielding layer that blocks light transmission, and an opening formed along the pattern of the height pattern layer, a filter that absorbs a predetermined wavelength at a predetermined ratio, the filter This is a step of exposing the photosensitive layer through the mask using a mask arranged in a part of the opening. For example, as shown in FIG. 1B, a mask 4 having a light shielding layer 3 and an opening 4 and a filter 5 provided in a part of the opening 4 is prepared. This is a step of exposing the photosensitive layer 2 formed from the photocurable resin composition to light.
[0047]
The mask used in such a main step will be described.
[0048]
(1) Mask
The mask in the present invention has a transparent substrate, a light-shielding layer formed on the transparent substrate and blocking light transmission, and an opening formed along a pattern of a high-low pattern layer described below, and A filter that absorbs a wavelength within a predetermined range at a predetermined ratio is provided at a part of the opening. Each member constituting such a mask in the present invention will be described.
[0049]
(1) Shading layer
The light-shielding layer has a role of preventing light from transmitting to an unexposed area of the photosensitive layer during exposure in this step, so as to prevent light from being transmitted. The material for forming such a light-shielding layer is not particularly limited as long as it is a material generally used as a light-shielding layer, and a material having excellent light-shielding properties is suitably used.
[0050]
In the present invention, among them, a metal chromium material can be preferably used. Further, a chromium oxide material may be formed thereon.
[0051]
Examples of a method for forming such a light-shielding layer include a vacuum deposition method, a sputtering method, and a CVD method. Particularly, among these, it is preferable to form a film by a sputtering method.
[0052]
As a method of forming an opening in such a light-shielding layer, for example, a resist is laminated on a light-shielding layer formed by a coating method described above on a transparent substrate, and the resist is irradiated with an electron beam or a laser or the like. Is drawn along the pattern of the high / low pattern layer. Thereafter, when the resist is developed, the resist is formed in a pattern. When etching is performed using the resist formed in the pattern, the exposed portion of the light-shielding layer is removed by removing the resist, and the etched portion becomes an opening.
[0053]
In the present invention, since the above-described photosensitive layer is a photo-curing type, the opening of the mask formed by the above-described method is formed along the pattern of the high / low pattern layer.
[0054]
▲ 2 ▼ Filter
The mask according to the present invention is characterized in that a filter is provided in a part of the opening. Such a filter is not particularly limited as long as it has a property of absorbing a wavelength within a predetermined range at a predetermined ratio. Specifically, the wavelength of the light to be absorbed needs to be in the range of 200 nm to 500 nm, and among them, it is preferable to be in the range of 300 nm to 450 nm. Further, the ratio of absorbing a wavelength within the above range is 40% or more. For the light source used when exposing the photocurable resin composition in the present invention, if the filter absorbs the wavelength within the above-mentioned range at the above ratio, the presence or absence of the filter is included in the light to be exposed. This is because a difference can be caused in the wavelength.
[0055]
The material for forming such a filter is not particularly limited as long as it has a property of absorbing a wavelength within the above-mentioned range in the above-mentioned range. Among them, it is preferable that the material is excellent in light transmittance for wavelengths outside the above-mentioned range. Specific examples include a film containing a coloring material such as a pigment and a dye, and a photosensitive resin containing a coloring material such as a pigment and a dye.
[0056]
Further, the method for forming a filter in the present invention is not particularly limited as long as it can be formed into a thin film using the above-described materials, and specifically, pigments, dyes, and the like are dispersed. Examples of the method include a method of laminating an adhesive film on a necessary region, a method of forming a photosensitive resin containing a coloring material such as a pigment and a dye on a necessary region, and the like.
[0057]
Furthermore, in the present invention, among filters that absorb light having a wavelength within the above-described range, two or more filters having different light transmittances may be used. Due to the difference in light transmittance of the filter, a difference in reactivity can be caused in the photocurable resin composition described above. As a result, in addition to the presence or absence of the filter, the pattern of the filter having the different light transmittance is different. Is provided, the low portion of the high / low pattern layer formed from the region exposed through the filter can be a low portion made of a combination of two or more different heights, and more various heights It is possible to form a high / low pattern layer due to the difference between the two.
[0058]
For example, when forming a high / low pattern layer consisting of a high part and one kind of low part depending on the presence or absence of a filter, or by providing two or more filters having different light transmittances in addition to the presence or absence of a filter, When forming a high / low pattern layer having a low portion composed of a combination of the above different heights, in advance, a difference in residual film ratio after development caused by the presence or absence of a filter and a filter having a different light transmittance were used. By determining the difference in the residual film ratio after the development in the case in an experiment, it is possible to adjust the high and low pattern layers.
[0059]
FIG. 5 shows a difference in film thickness due to a change in the exposure amount when two types of yellow filters having a transmittance of light of 200 nm to 500 nm of 10% and 40% are used and when exposure is performed without using a filter. The result of the measurement is shown.
[0060]
The black circles indicate the film thickness when exposed without passing through a filter, and the black triangles indicate the film thickness when exposed through a yellow filter having a light transmittance of 200% to 500 nm of 40%. A black square indicates a film thickness when exposed through a yellow filter having a transmittance of light of 200% to 500 nm of 10%.
[0061]
From the results shown in FIG. 5, it can be seen that there is a difference in the film thickness at each exposure dose depending on the presence or absence of the yellow filter and the difference in light transmittance. That is, based on such an experimental result, by selecting a filter and an exposure amount that cause a desired film thickness difference, a high / low pattern layer including a high portion and a low portion having a desired film thickness and the difference is obtained. Can be formed.
[0062]
(2) Exposure
In this step, pattern exposure is performed on the photosensitive layer via the mask described above. As the light source used at this time, a light source capable of irradiating light capable of curing the photocurable resin composition can be mentioned. Specifically, a light source including ultraviolet light can be used. Can be used. As a light source of light including such ultraviolet light, for example, a mercury lamp, a metal halide lamp, a xenon lamp, and the like can be given. In addition, the exposure amount of light at the time of exposure is an exposure amount sufficient to cure the photosensitive layer in a portion corresponding to the opening where the filter is not arranged.
[0063]
3. High / low pattern layer forming process
Next, a step of forming a high / low pattern layer will be described. The height pattern layer forming step in the present invention is to develop the photosensitive layer exposed by the above-described exposure step, and to adjust the height of the photosensitive layer corresponding to the region where the filter is disposed in the opening of the mask to be a low portion. This is a step of forming a pattern layer.
[0064]
In the present invention, at the time of the above-described exposure step, since pattern exposure is performed through a mask in which a filter is disposed in a part of the opening, even in an exposed area exposed in the photosensitive layer, There is a difference in reactivity of the photosensitive layer depending on the presence or absence. Therefore, when such a photosensitive layer is developed in this step, the photosensitive layer in the unexposed area is removed, while the photosensitive layer in the exposed area becomes a high part and a low part whose film thickness differs depending on the presence or absence of a filter. A high / low pattern layer including a high portion and a low portion is formed. Hereinafter, the height pattern layer formed by this step will be described.
[0065]
(High and low pattern layer)
The high / low pattern layer in the present invention is a layer in which high portions and low portions having different heights are combined in a pattern.
[0066]
The high portion constituting such a high / low pattern layer is the thickest portion of the high / low pattern layer, and in the above-described exposure step, the portion formed from the photosensitive layer corresponding to the opening without a filter is used. Is shown. Since the high portion is formed from the photosensitive layer to which the light irradiated from the light source is exposed as it is, curing proceeds more rapidly in the above-described exposure step than in the low portion described later, and the residual film ratio after development is lower. It is the highest.
[0067]
On the other hand, the low part is a part excluding the above-mentioned high part in the high / low pattern layer, and means a part formed from the photosensitive layer corresponding to the opening where the filter is arranged. Since the low portion is exposed to light that has passed through the filter, curing proceeds more slowly in the above-described exposure step than in the high portion, and the residual film ratio after development is lower than that in the high portion. is there. Such a lower portion may be a lower portion having a uniform height, or may be a lower portion formed of a combination of a plurality of different heights. That is, in the above-described mask, when a filter having the same light transmittance is disposed in a part of the opening, a low portion having a uniform height is formed, but the light transmittance is low. This is because when two or more different filters are used, two or more different heights are generated even in the lower part. Such a low portion is selected according to the use of the high-low pattern layer forming body.
[0068]
The difference in film thickness between the high part and the low part, and the respective film thicknesses are determined according to the use of the high-low pattern layer forming body.
[0069]
The developer used in this step is determined according to the photocurable resin composition used. Specifically, an aqueous solution of potassium hydroxide, an aqueous solution of sodium carbonate, an aqueous solution of sodium hydrogen carbonate, an aqueous solution of TMAH, and the like can be given. When the photocurable resin composition is formed on a member other than the substrate, it is necessary to use a developer that does not dissolve such a member.
[0070]
4. Obtained high-low pattern layer formed body
Next, the high / low pattern layer-formed body obtained by the method for manufacturing a high / low pattern layer-formed body of the present invention will be described. The height pattern layer forming body according to the present invention includes a substrate and a height pattern layer formed on the substrate and having a combination of patterns having different heights.
[0071]
The use of such a high / low pattern layer formed body is not particularly limited as long as it has members made of the same material and having different heights. Specifically, a substrate for a liquid crystal display can be used.
[0072]
Note that the liquid crystal display substrate referred to here is a liquid crystal display that sandwiches a liquid crystal layer therein, and includes, for example, a color filter side substrate having a color filter, an array side substrate having a thin film transistor, and the like. An on-chip type substrate in which a color filter is formed directly on a thin film transistor can be used.
[0073]
In the present invention, among the substrates for a liquid crystal display, a substrate for a monochrome liquid crystal display and an MVA mode liquid crystal display are preferable.
[0074]
In a substrate for a monochrome liquid crystal display, pixel spacers located in a pixel portion, which is a display region of the monochrome liquid crystal display, and outer peripheral spacers located in an outer periphery, which is outside the display region of the monochrome liquid crystal display, are formed at different heights. In such a case, in such a case, by utilizing the high / low pattern layer in the present invention for the pixel spacer and the outer peripheral spacer, it is possible to simultaneously form the pixel spacer and the outer peripheral spacer with the same material, thereby reducing the manufacturing efficiency. Can be improved.
[0075]
On the other hand, in the MVA mode liquid crystal display, an alignment control projection for controlling the alignment of the liquid crystal, and a columnar spacer for MVA for maintaining a constant distance from the counter substrate are formed of the same material in different patterns and different heights. Therefore, it is advantageous in terms of manufacturing efficiency by forming such alignment control projections and MVA columnar spacers as high and low pattern layers.
[0076]
Hereinafter, a method for manufacturing a substrate for a monochrome liquid crystal display and a method for manufacturing an MVA mode liquid crystal display will be described.
[0077]
B. Method for manufacturing substrate for monochrome liquid crystal display
The method for manufacturing a substrate for a monochrome liquid crystal display of the present invention is a method for manufacturing a substrate for a monochrome liquid crystal display using the method for manufacturing a high / low pattern layer forming body described above, wherein the high / low pattern layer is used for displaying the monochrome liquid crystal display. Pixel spacers located in the area and outer peripheral spacers located outside the display area of the monochrome liquid crystal display,
A substrate preparing step of preparing a substrate having a black matrix formed in a pattern and a protective layer formed so as to cover the black matrix formed in the pattern,
Applying a photocurable resin composition on the substrate, a photosensitive layer forming step of forming a photosensitive layer,
A light-blocking layer that blocks light transmission, a pixel opening formed along the pattern of the pixel spacer, and an outer peripheral opening formed along the pattern of the outer peripheral spacer; An exposure step of exposing the photosensitive layer through the mask using a mask arranged at least in the outer peripheral opening, wherein the filter absorbs 40% or more of the wavelength of
By developing the exposed photosensitive layer, a pixel spacer formed on the protective layer in an area where the black matrix is formed and located in a pixel portion which is a display area of a monochrome liquid crystal display, and a display of the liquid crystal display A columnar spacer forming step of forming a columnar spacer including an outer peripheral spacer located on an outer peripheral portion outside the region.
[0078]
In the present invention, since a filter having a property of absorbing a wavelength in the above-described range in the above-described range is arranged at least in the outer peripheral opening of the mask, the pixel spacer and the outer periphery having different heights using the same material are used. Spacers can be formed simultaneously. As a result, it is possible to avoid the influence of the difference in the film thickness between the outer peripheral portion and the pixel portion of the protective layer caused by the difference in the line width of the black matrix between the outer peripheral portion and the pixel portion. In the substrate, the difference between the height from the substrate surface to the upper end surface of the outer peripheral spacer and the height from the substrate surface to the upper end surface of the pixel spacer can be adjusted within a suitable range. Therefore, disposing the opposing substrate on such a substrate for a monochrome liquid crystal display prevents the opposing substrate from being distorted so as to widen the gap toward the outer peripheral portion, and causes a problem that light leaks from the periphery of the opposing substrate. It becomes difficult. This can solve the problem that the periphery of the screen becomes unnaturally bright in the monochrome liquid crystal display.
[0079]
Hereinafter, the substrate for a monochrome display device of the present invention will be described with reference to the drawings. FIG. 2 is a process chart showing an example of a method for manufacturing a substrate for a monochrome display device of the present invention.
[0080]
First, as shown in FIG. 2A, a black matrix 12 for partitioning pixels is formed in a pattern on a transparent substrate 30 of a monochrome liquid crystal device substrate. The black matrix 12 includes a pixel black matrix 12a formed in a pixel portion A which is a display region of a monochrome liquid crystal display, and an outer black matrix 12b formed in an outer portion B which is outside the display region. Are formed differently. Specifically, the pixel black matrix 12a has a narrow line width in order to prevent a decrease in the aperture ratio of the display area, while the outer peripheral black matrix 12b has a wide line width in order to block light from a light source. Form.
[0081]
Next, members such as the black matrix 12 are protected on the transparent substrate 30 of the monochrome liquid crystal display substrate on which the black matrix 12 is formed, as shown in FIG. In order to provide flatness, a protective layer 13 is formed so as to cover the surface of the black matrix 12. In such a protective layer 13, a difference occurs in the film thickness on each black matrix 12 due to a difference in line width between the pixel black matrix 12a and the outer peripheral black matrix 12b. That is, since the pixel black matrix 12a has a small line width, the thickness of the protective layer 13 stacked on the upper surface of the pixel black matrix 12a tends to be thin. On the other hand, since the outer peripheral black matrix 12b is formed to have a line width sufficient for the protective layer 13 to be laminated, the thickness of the protective layer 13 laminated on the upper surface is the same as that of the upper surface of the pixel black matrix 12a. This is because the thickness is larger than the thickness of the protective layer 13.
[0082]
Further, as shown in FIG. 2C, a photosensitive layer 14 is formed on the protective layer 13. Next, a mask 16 used for patterning the photosensitive layer 14 is prepared. The mask 16 has a light-shielding layer 17, a pixel opening 18a corresponding to a position where a pixel spacer is formed, and an outer peripheral opening 18b corresponding to a position where an outer peripheral spacer is formed. Further, a filter 19 having a property of absorbing a predetermined range of wavelengths within a predetermined range is disposed in the outer peripheral opening 18b. As shown in FIG. 2D, the photosensitive layer 14 is subjected to pattern exposure through such a mask 16. In the present invention, since the filter 19 is disposed in the outer peripheral opening 18 b of the mask 16, the photosensitive layer 14 in a portion corresponding to the outer peripheral opening 18 b is controlled by the filter 19 so that the wavelength within a predetermined range is a predetermined ratio. Since the absorbed light is exposed, the curing progresses more slowly than the photosensitive layer 14 in the portion corresponding to the pixel opening 18a.
[0083]
Then, when the photosensitive layer 14 that has been subjected to the pattern exposure is developed and washed, as shown in FIG. 2E, the portion of the photosensitive layer 14 that has become an unexposed area is removed by the light shielding layer 17 of the mask 16, and the pixel opening is removed. A portion of the photosensitive layer 14 which has become an exposure region due to the outer periphery 18a and the outer peripheral opening 18b remains. As a result, the pixel spacer 20a located in the pixel portion A and the outer peripheral spacer 20b located in the outer peripheral portion B are formed on the protective layer 13 in the region where the black matrix 12 is formed. Further, in the present invention, since the pattern exposure is performed only in the outer peripheral opening 18b by disposing the filter 19 having a property of absorbing a predetermined range of wavelengths within a predetermined range, the outer peripheral spacer 20b is more preferable. The film thickness is formed smaller than the pixel spacer 20a. As a result, a substrate for a monochrome liquid crystal display that can eliminate the influence of the difference in film thickness between the pixel portion A and the outer peripheral portion B of the protective layer 13 is obtained.
[0084]
Finally, as shown in FIG. 2F, when the opposing substrate 21 is attached to such a substrate for a monochrome liquid crystal display, in the present invention, the height from the surface of the transparent substrate 30 to the upper end surface of the pixel spacer 20a is reduced. In addition, since the height from the surface of the transparent substrate 30 to the upper end surface of the outer peripheral spacer 20b can be a monochromatic liquid crystal display substrate having a good uniformity, the counter substrate 21 is not disadvantageously distorted. Since there is no possibility of light from leaking from around the opposing substrate 21 or the like, the problem that the periphery of the display screen becomes unnaturally bright can be solved.
[0085]
Here, the “pixel portion” means a portion that becomes a display area where monochrome display is actually performed when a monochrome liquid crystal display is formed using the substrate for a monochrome liquid crystal display of the present invention. Further, the “peripheral portion” means a portion located around the pixel portion and outside the above-described display area.
[0086]
Hereinafter, a method for manufacturing a substrate for a monochrome display device of the present invention having such advantages will be described for each step.
[0087]
1. Substrate preparation process
First, the substrate preparation step will be described. The substrate preparing step in the present invention is a step of preparing a substrate having a black matrix formed in a pattern and a protective layer formed so as to cover the black matrix formed in the pattern.
[0088]
Hereinafter, the black matrix, the protective layer, and the substrate will be described.
[0089]
(1) Black matrix
The black matrix used in the present invention is provided for separating pixels for performing monochrome display according to the orientation of liquid crystal molecules. The method for producing such a black matrix is not particularly limited. For example, a metal thin film of chromium or the like having a thickness of about 1000 to 2000 mm is formed by, for example, a sputtering method or a vacuum evaporation method, and the thin film is patterned. And the like.
[0090]
In such a black matrix, a pixel portion is formed to have a narrow line width in order to increase an aperture ratio of a display region. On the other hand, the outer peripheral portion is provided wider than the black matrix of the pixel portion in order to effectively shield light from a light source such as a backlight. Specifically, the line width of the black matrix provided in the pixel portion is generally in the range of 6 μm to 20 μm, while the line width of the black matrix in the outer peripheral portion is in the range of 2 mm to 10 mm.
[0091]
Further, as the black matrix, carbon fine particles, metal oxides, inorganic pigments, light-shielding particles such as organic pigments and the like may be contained in a resin binder, and as the resin binder used, polyimide resin, acrylic resin, epoxy resin Resin, polyacrylamide, polyvinyl alcohol, gelatin, casein, cellulose, or a mixture of two or more resins, a photosensitive resin, and a resin composition of an O / W emulsion type, for example, a reactive silicone. Emulsified products can be used. As a method for patterning such a resinous black matrix, a commonly used method such as a photolithography method and a printing method can be used.
[0092]
(2) Protective layer
The protective layer in the present invention is provided on a substrate on which the above-described black matrix or the like is formed, to protect these members and to impart flatness to the substrate surface of the substrate for a monochrome liquid crystal display.
[0093]
Materials for forming such a protective layer include acrylic resin, ethylene-vinyl acetate copolymer, ethylene-vinyl chloride copolymer, ethylene vinyl copolymer, polystyrene, acrylonitrile-styrene copolymer, ABS resin, and polystyrene. Methacrylic acid resin, ethylene methacrylic acid resin, polyvinyl chloride resin, chlorinated vinyl chloride, polyvinyl alcohol, cellulose acetate propionate, cellulose acetate butyrate, nylon 6, nylon 66, nylon 12, polyethylene terephthalate, polybutylene terephthalate, polycarbonate , Polyvinyl acetal, polyether ether ketone, polyether sulfone, polyphenylene sulfide, polyarylate, polyvinyl butyral, epoxy resin, phenoxy resin, polyamide Resin, polyamideimide resin, polyamic acid resin, polyetherimide resin, phenol resin, urea resin, etc., and polymerizable monomers methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, n-propyl acrylate, n- Propyl methacrylate, isopropyl acrylate, isopropyl methacrylate, sec-butyl acrylate, sec-butyl methacrylate, isobutyl acrylate, isobutyl methacrylate, tert-butyl acrylate, tert-butyl methacrylate, n-pentyl acrylate, n-pentyl methacrylate, n-hexyl acrylate, n-hexyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate Acrylate, n-octyl acrylate, n-octyl methacrylate, n-decyl acrylate, n-decyl methacrylate, styrene, α-methylstyrene, N-vinyl-2-pyrrolidone, glycidyl (meth) acrylate, and acrylic acid , Methacrylic acid, dimer of acrylic acid (for example, M-5600 manufactured by Toa Gosei Chemical Co., Ltd.), itaconic acid, crotonic acid, maleic acid, fumaric acid, vinyl acetic acid, and one or more of these acid anhydrides and the like. A photosensitive resin composition containing one or more kinds of polymers or copolymers is exemplified. Among them, a photosensitive resin composition using an acrylic resin is preferable from the viewpoint of flatness required as a protective layer.
[0094]
The thickness of the protective layer is not particularly limited as long as it can provide flatness on the substrate, but specifically, in the range of 0.3 μm to 10 μm, among them, It is preferable that the thickness be in the range of 0.7 μm to 2 μm.
[0095]
As a method of forming such a protective layer, it is possible to form by a known coating method, a spin coating method, a casting method, a dipping method, a bar coating method, a blade coating method, a roll coating method, a gravure coating method, Coating methods such as flexographic printing and spray coating can be used.
[0096]
Note that the difference in film thickness between the pixel portion and the outer peripheral portion of the protective layer laminated on the black matrix differs depending on the difference in line width in both portions of the actually formed black matrix and the material for forming the protective layer. However, it is generally difficult to specify them generally, but in general, it is often in the range of 0 μm to 0.5 μm.
[0097]
(3) Substrate
The substrate of the substrate for a monochrome liquid crystal display in the present invention is for mounting other constituent members. As such a substrate, for example, a glass substrate, a glass film, a synthetic resin substrate, a synthetic resin film, or the like is used. It is preferable that the material has excellent light transmittance.
[0098]
2. Photosensitive layer forming process
Next, the photosensitive layer forming step will be described. The photosensitive layer forming step in the present invention is a step of applying a photocurable resin composition on the substrate to form a photosensitive layer. Specifically, as shown in FIG. 2C, a transparent substrate having a black matrix 12 formed in a pattern and a protective layer 13 formed on a transparent substrate 30 so as to cover the black matrix 12 In step 30, a photocurable resin composition is applied on the protective layer 13 to form the photosensitive layer 14.
[0099]
The photosensitive layer formed in this step is formed in a pattern in a columnar spacer forming step described later, and becomes a pixel spacer and an outer peripheral spacer that keep a constant gap between the monochrome liquid crystal display substrate and the counter substrate. Layer. Further, in the present invention, since the photosensitive layer is patterned by using the above-described method for manufacturing a high / low pattern layer forming body, pixel spacers and peripheral spacers having different heights are simultaneously formed using the same material. be able to.
[0100]
Other details of this step are the same as those described in the above-mentioned “A. Method for manufacturing high / low pattern layer-formed body, 1. Photosensitive layer forming step”, and thus description thereof will be omitted.
[0101]
3. Exposure process
Next, the exposure step will be described. The exposure step in the present invention includes a light-shielding layer that blocks transmission of light, a pixel opening formed along the pattern of the pixel spacer, and an outer peripheral opening formed along the pattern of the outer peripheral spacer. A filter that absorbs at least 40% of the wavelength in the range of 200 nm to 500 nm, preferably in the range of 300 nm to 450 nm, using a mask disposed at least in the outer peripheral opening, and through the mask, This is a step of exposing the photosensitive layer.
[0102]
Here, the outer peripheral opening means a portion where the light shielding layer is removed along the pattern of the outer peripheral spacer. Since the outer peripheral spacer is a columnar spacer located at the outer peripheral portion, the outer peripheral opening is also formed at a portion corresponding to the outer peripheral portion of the mask. Further, the pixel opening here means a portion where the light shielding layer is removed along the pattern of the pixel spacer. Since the pixel spacer is a columnar spacer located in the pixel portion, the pixel opening is also formed in a portion corresponding to the pixel portion of the mask.
[0103]
In the present invention, the difference in film thickness between the outer peripheral portion of the protective layer and the pixel portion caused by the difference in the line width between the outer peripheral portion of the black matrix and the pixel portion is reduced by providing the outer peripheral spacer and the pixel spacer having different heights. It will be resolved. That is, since the thickness of the protective layer tends to be larger in the outer peripheral portion than in the pixel portion, in order to eliminate such a difference in the thickness of the protective layer, the outer peripheral spacer is set to be lower than the pixel spacer. Need to be formed.
[0104]
Therefore, in the present invention, in the above-mentioned high-low pattern layer, the above-mentioned filter is arranged in the outer-peripheral opening of the mask formed in the pattern of the outer-peripheral spacer so that the lower part is the outer-peripheral spacer and the higher part is the pixel spacer. ing. Thereby, the portion that can be the outer peripheral spacer of the photosensitive layer is exposed to light that has passed through the filter, so that the curing proceeds more slowly than the portion that can be the pixel spacer of the photosensitive layer that is exposed without passing through the filter, In the columnar spacer forming step described later, the residual film ratio after development is reduced.
[0105]
Other details of this step are the same as those described in the above-mentioned “A. Manufacturing method of high / low pattern layer formed body, 2. Exposure step”, and thus description thereof will be omitted.
[0106]
4. Column spacer formation process
Finally, a columnar spacer forming step will be described. The columnar spacer forming step in the present invention refers to a step of developing the exposed photosensitive layer described above to position the pixel layer, which is a display area of a monochrome liquid crystal display, on the protective layer in the area where the black matrix is formed. This is a step of forming a columnar spacer including a pixel spacer to be formed and an outer peripheral spacer located at an outer peripheral portion outside the display area of the monochrome liquid crystal display.
[0107]
(Columnar spacer)
The columnar spacer according to the present invention is disposed between two substrates that sandwich a liquid crystal layer therein, and is provided to maintain a constant gap between the two substrates. In such columnar spacers, in the present invention, a columnar spacer disposed in a pixel portion corresponding to a display area of a monochrome liquid crystal display is defined as a pixel spacer, and a columnar spacer disposed in an outer peripheral portion corresponding to outside the display area is defined as an outer peripheral spacer. And
[0108]
In the present invention, such a pixel spacer and an outer peripheral spacer can be simultaneously formed using the same material by photolithography so as to have different heights.
[0109]
That is, in the above-described exposure step, since at least the outer peripheral opening portion uses a mask in which a filter having a property of absorbing a wavelength within a predetermined range in a predetermined range is used, photo-curing is performed with or without the filter. A difference can be caused in the degree of curing of the mold resin composition. Thereby, it is possible to form the pixel spacer thicker than the outer peripheral spacer.
[0110]
Further, the relationship between the height of the pixel spacer and the height of the outer peripheral spacer is such that the height of the pixel spacer is such that no undesired distortion occurs between the two substrates when the opposing substrate is bonded to the substrate for monochrome liquid crystal display. There is no particular limitation as long as it is higher than the height of the outer peripheral spacer. This is because the thickness of the protective layer is formed thinner in the pixel portion than in the outer peripheral portion due to the difference in width between the pixel portion and the outer peripheral portion of the black matrix. By making the thickness higher than that, the difference in the thickness of the protective layer can be corrected by the columnar spacer.
[0111]
Specifically, the difference in height between the pixel spacer and the outer peripheral spacer is adjusted according to the difference in film thickness between the pixel portion and the outer peripheral portion of the protective layer formed on the black matrix. For example, at the stage when the protective layer is formed, the state of the monochrome liquid crystal display substrate is grasped by measuring the difference in the film thickness of the protective layer or by performing a simulation or the like, and the pixel spacer and the outer periphery are determined according to the state. Adjust the difference in spacer height. Furthermore, in order to make the difference between the height of the pixel spacer and the outer peripheral spacer a desired difference, the residual film ratio of the photosensitive layer in accordance with the change of the filter and the exposure amount is measured by an experiment. This can be achieved by determining a filter, an exposure amount, and the like suitable for the state of the display substrate.
[0112]
In addition, since the difference in height between the pixel spacer and the outer peripheral spacer is adjusted according to the difference in film thickness between the outer peripheral portion of the protective layer and the pixel portion, it is difficult to unconditionally define the difference, but it can generally occur. When defined based on the difference in the thickness of the protective layer, the height of the pixel spacer itself is preferably higher than the height of the outer peripheral spacer in the range of 0 μm to 1.3 μm, and among them, 0.5 μm to 1 μm. It is preferable that the height is formed within a range of 0.1 μm. If the pixel spacer and the outer peripheral spacer can be formed with a difference in height within the above range, the height from the substrate surface of the monochrome liquid crystal display substrate to the upper surface of the pixel spacer can be increased from the same substrate surface to the upper surface of the outer peripheral spacer of the substrate. The height can be made higher in the range of 0 μm to 0.8 μm than the height up to, so that the two substrates are arranged while maintaining a highly uniform gap without causing inconvenient distortion of the opposite substrate. Because it can be.
[0113]
The height of the pixel spacer itself is not particularly limited as long as it is a height used in a general monochrome liquid crystal display, and specifically, is in a range of 2.5 μm to 5.5 μm. Is preferred.
[0114]
Furthermore, the shape of the columnar spacer in the present invention is not particularly limited as long as it is a shape that can keep the gap between the two substrates constant. Specifically, a columnar shape, a prismatic shape, a truncated cone shape, or the like can be given.
[0115]
C. Method for manufacturing MVA mode liquid crystal display
Next, a method for manufacturing an MVA mode liquid crystal display will be described. The method for manufacturing an MVA mode liquid crystal display of the present invention is a method for manufacturing an MVA mode liquid crystal display using the above-described method for manufacturing a high / low pattern layer formed body,
The height pattern layer is an alignment control projection and an MVA columnar spacer used in the MVA mode liquid crystal display;
The mask includes a light-blocking layer that blocks transmission of light, a first opening formed along the pattern of the alignment control protrusions, and a second opening formed along the pattern of the MVA columnar spacer. And the filter is arranged at least in the first opening.
[0116]
In the present invention, the alignment control projections and the MVA columnar spacers used in the MVA mode liquid crystal display can be simultaneously manufactured using the same material by the photolithography method.
[0117]
The method for manufacturing the MVA mode liquid crystal display mode liquid crystal display of the present invention having such advantages will be specifically described with reference to the drawings.
[0118]
FIG. 3 is a process chart showing an example of a method for manufacturing an MVA mode liquid crystal display of the present invention. First, as shown in FIG. 3A, a photocurable resin composition is applied on a transparent substrate 31 to form a photosensitive layer 32. Next, as shown in FIG. 3B, the light-shielding layer 33 that blocks light transmission, the first opening 34a formed along the pattern of the alignment control protrusion, and the pattern of the MVA columnar spacer are formed. A mask 36 having a second opening 34b formed therein and a filter 35 having a property of absorbing a predetermined range of wavelengths in a predetermined range disposed in the first opening 34a is prepared. The photosensitive layer 32 is exposed through the mask 36. Accordingly, a pattern based on the presence or absence of the filter 35 can be formed on the photosensitive layer 32 between the first opening 34a and the second opening 34b. Next, by developing and washing the exposed photosensitive layer 32, as shown in FIG. 3C, the photosensitive layer 32 in an unexposed area where light transmission is blocked by the light shielding layer 33 is removed. The portion of the photosensitive layer 32 that has become an exposure region by the first opening 34a and the second opening 34b remains. Further, in the present invention, since the filter 35 is disposed in the first opening 34a, even in the case of the exposure area, the exposure area corresponding to the first opening 34a is the second opening 34a. The degree of curing is lower than that of the exposed area corresponding to the portion 34b. Therefore, as shown in FIG. 3C, the exposed area corresponding to the first opening 34a becomes the alignment control projection 37 and the second opening 34a. The exposure area corresponding to the portion 34b becomes the MVA columnar spacer 38. Further, the thickness of the alignment control protrusion is formed to be smaller than that of the columnar spacer for MVA.
[0119]
Hereinafter, the method for manufacturing the MVA mode liquid crystal display of the present invention will be described for each step.
[0120]
1. Photosensitive layer forming process
The photosensitive layer forming step in the present invention is a step of applying a photocurable resin composition on a substrate to form a photosensitive layer.
[0121]
This step is the same as the above-mentioned "A. Method for manufacturing a high / low pattern layer-formed body, 1. photosensitive layer forming step", and thus description thereof will be omitted.
[0122]
2. Exposure process
Next, the exposure step according to the present invention includes a light-shielding layer that blocks light transmission, a first opening formed along the pattern of the alignment control protrusions, and a first opening formed along the pattern of the MVA columnar spacer. A filter having two openings and absorbing at least 40% of a wavelength in the range of 200 nm to 500 nm using a mask arranged at least in the first opening, and exposing the photosensitive layer through the mask; This is the step of doing.
[0123]
Here, the first opening means a portion where the light shielding layer is removed along the pattern of the alignment control projection. Further, the second opening here means a portion where the light shielding layer is removed along the pattern of the MVA columnar spacer.
[0124]
In the present invention, the first opening of the mask formed in the pattern of the orientation control protrusions is such that the lower portion becomes the orientation control protrusion and the higher portion becomes the columnar spacer for MVA in the above-mentioned height pattern layer. A filter is placed. Thereby, the portion that can be the alignment control projection of the photosensitive layer is exposed to light that has passed through the filter, and thus cures more slowly than the portion that can be the MVA columnar spacer of the photosensitive layer that is exposed without passing through the filter. As a result, the residual film ratio after development is reduced in the MVA columnar spacer forming step described later.
[0125]
Other details of this step are the same as those described in the above-mentioned “A. Manufacturing method of high / low pattern layer formed body, 2. Exposure step”, and thus description thereof will be omitted.
[0126]
3. Step of forming alignment control protrusion and columnar spacer for MVA
Finally, the step of forming the alignment control protrusion and the columnar spacer for MVA will be described. The step of forming the alignment control projection and the columnar spacer for MVA in the present invention is a step of forming the alignment control projection and the columnar spacer for MVA by developing the exposed photosensitive layer in the above-described exposure step.
[0127]
The alignment control protrusions and the MVA columnar spacers formed in this step will be described.
[0128]
(1) Orientation control protrusion
The orientation control protrusion in the present invention means a protrusion for controlling the alignment of the liquid crystal layer. Since the liquid crystal molecules in contact with the alignment control projections are aligned in a direction perpendicular to the contact surface with the alignment control projections, when a voltage is applied to the liquid crystal layer, the tilted liquid crystal molecules near the projections start from the inclined liquid crystal molecules. As a result, each liquid crystal molecule can be oriented in a predetermined direction. Thus, the liquid crystal can be symmetrically aligned at an angle of 180 degrees in the horizontal direction and at an angle inclined in the vertical direction with the vertex of the alignment control protrusion as a boundary. Then, by forming two pixels adjacent to each other as one set and further combining these combinations to display one pixel, the observer always keeps the same even if the observer's viewing angle is changed in the vertical direction of the alignment control protrusion. You can see the image. That is, a wide viewing angle can be secured. The alignment control projection is preferably linear (especially zigzag linear), but is not limited thereto, and may be dotted or the like.
[0129]
In the present invention, such alignment control projections are simultaneously manufactured using the same material as the MVA columnar spacers described later, and such that the MVA columnar spacers are thicker than the alignment control projections. It is characterized by the following.
[0130]
The height of such an alignment control projection is not particularly limited as long as it is lower than a columnar spacer for MVA described later, but is preferably 0.5 to 2 μm.
[0131]
Further, in the present invention, it is preferable that such alignment control projections are provided in a zigzag line shape refracted by 90 degrees at predetermined intervals, and each zigzag line is formed in a stripe shape parallel to each other. . Thereby, completely symmetrical viewing angle characteristics can be obtained not only in the vertical direction of the alignment control projection line but also in all directions of up, down, left, and right. That is, the orientation of the liquid crystal molecules having 180-degree symmetry in the horizontal direction is different by 90 degrees between two regions adjacent to each other with the 90-degree refraction angle of the alignment control projection line as a boundary. For this reason, the liquid crystal molecules are divided into four regions at the boundary of the refraction angle and the alignment control protrusion, and the orientation angle of the major axis of the liquid crystal molecule between the four regions is in the horizontal direction with respect to the center axis of the zigzag line. At a 45 ° angle and vertically inclined at four angles. In this manner, one pixel can be divided into four and displayed at symmetrical angles, so that the observer can always see the same image in all directions, up, down, left, and right.
[0132]
(2) Columnar spacer for MVA
Next, the columnar spacer for MVA will be described. The columnar spacer for MVA in the present invention is provided to keep the distance between the liquid crystal layers held between two substrates uniform and to regulate the thickness of the liquid crystal layer.
[0133]
In the present invention, such an MVA columnar spacer is made of the same material at the same time as the above-described orientation control projection, and the MVA columnar spacer is thicker than the orientation control projection. It is manufactured by a photolithography method.
[0134]
Such a column spacer for MVA is not particularly limited as long as it does not adversely affect the luminance of the liquid crystal display, but is preferably provided at a position overlapping the alignment control projection. Thereby, the range of selection of the size of the columnar spacer for MVA can be expanded without reducing the luminance of the liquid crystal display. Note that the columnar spacer for MVA may protrude slightly from the alignment control protrusion or may be provided narrower than the alignment control protrusion as long as the position overlaps with the alignment control protrusion. When the alignment control projection is formed in a zigzag shape, the alignment control projection may be provided in a zigzag bent portion or in a linear portion other than the bent portion, and is not particularly limited. Further, the columnar spacer for MVA and the above-mentioned alignment control projection may be colored or transparent, and are not particularly limited.
[0135]
When the MVA columnar spacer is provided so as to overlap with the alignment control projection, the MVA columnar spacer is provided so as to coincide with the refraction portion (apex) of the zigzag line even in a portion overlapping with such an alignment control projection. Is preferred. When a voltage is applied, on a line connecting the refraction portions, liquid crystal molecules tilted from two directions come close to each other. Therefore, the liquid crystal molecules have an alignment direction almost perpendicular to the line, and light transmittance is significantly reduced. For this reason, the vicinity of the line connecting the bending portions is always dark, and by disposing the MVA columnar spacer at such a position, the inconvenience exerted by both can be integrated into one place. . That is, by forming the columnar spacers for MVA on the alignment control projections, it is possible to prevent any influence on the alignment of the liquid crystal. In addition, when the alignment control projection is formed of a transparent material, if a spacer is formed other than the refraction portion even on the alignment control projection, the MVA columnar spacer may be observed as a black point during white display. However, there is also an advantage that such inconvenience can be prevented by forming the MVA columnar spacer on the bending portion.
[0136]
The height of the columnar spacer for MVA is preferably in the range of 1 to 10 μm, more preferably in the range of 2 to 10 μm, and further preferably in the range of 1 to 8 μm. .
[0137]
Note that the present invention is not limited to the above embodiment. The above embodiment is an exemplification, and the present invention has substantially the same configuration as the technical idea described in the claims of the present invention, and has the same effect. Within the technical scope of
[0138]
【Example】
Hereinafter, the present invention will be further described with reference to Examples.
[0139]
[Example]
A 5 μm film was formed on the substrate by spin coating using an Optmer NN series manufactured by JCR Corporation as a material for forming a high / low pattern layer. This film was exposed at 20 to 100 mJ / cm using a photomask having a filter having a property of transmitting 10% and 40% of a wavelength in the range of 200 nm to 500 nm through a gap of 100 μm. This was developed with a 0.05 wt% KOH aqueous solution for 60 seconds. Thereafter, by baking at 230 ° C. for 30 seconds, a high / low pattern layer including a high portion and a low portion having different heights as shown in FIG. 5 could be simultaneously formed using the same material.
[0140]
【The invention's effect】
According to the present invention, since a filter having a property of absorbing 40% or more of a wavelength in the range of 200 nm to 500 nm is arranged in a part of the opening, the photosensitive layer which has become an exposure region in the exposure step. However, depending on the presence or absence of the filter, a difference in the residual film ratio after development can be caused. Therefore, there is an effect that the high and low pattern layers including the high portion and the low portion having different heights can be simultaneously formed using the same material.
[Brief description of the drawings]
FIG. 1 is a process chart showing an example of a method for manufacturing a high / low pattern layer according to the present invention.
FIG. 2 is a process chart showing an example of a method for manufacturing a substrate for a monochrome liquid crystal display of the present invention.
FIG. 3 is a process chart showing an example of a method for manufacturing an MVA mode liquid crystal display of the present invention.
FIG. 4 is a process chart showing an example of a conventional substrate for a monochrome liquid crystal display.
FIG. 5 is a graph showing the film thickness after development with a change in the exposure amount of the photosensitive layer when light is exposed without passing through a filter and when two types of filters having different light transmittances are used.
[Explanation of symbols]
1 ... substrate
2 Photosensitive layer
3 ... light shielding layer
4 ... opening
5 ... Filter
6 ... mask
7, 8 ... Exposure area
9 ... unexposed area
10… low part
11 ... Takabe

Claims (5)

A substrate, having a high / low pattern layer formed on the substrate and having a combination of patterns having different heights, wherein the high / low pattern layer is simultaneously manufactured with the same material by a photolithography method. A manufacturing method,
Applying a photocurable resin composition on the substrate, a photosensitive layer forming step of forming a photosensitive layer,
A filter having a light-blocking layer that blocks light transmission and an opening formed along the pattern of the high / low pattern layer, and a filter that absorbs 40% or more of a wavelength in the range of 200 nm to 500 nm is provided at one of the openings. Using a mask arranged in the portion, through the mask, an exposure step of exposing the photosensitive layer,
By developing the exposed photosensitive layer, a high-low pattern layer forming step of forming a high-low pattern layer in which the photosensitive layer corresponding to the region where the filter is disposed in the opening of the mask becomes a lower part,
A method for producing a high / low pattern layer formed body, comprising: The method of claim 1, wherein the photocurable resin composition has different reactivity depending on the intensity of light within a range of 200 nm to 500 nm. 3. The method according to claim 1, wherein the height pattern layer forming body is used for a liquid crystal display substrate. A method for manufacturing a substrate for a monochrome liquid crystal display using the method for manufacturing a high / low pattern layer forming body according to any one of claims 1 to 3,
The height pattern layer is a pixel spacer located in the display area of the monochrome liquid crystal display and an outer peripheral spacer located outside the display area of the monochrome liquid crystal display,
The mask has a light-blocking layer that blocks light transmission, a pixel opening formed along the pixel spacer pattern, and an outer peripheral opening formed along the outer spacer pattern, and at least the A method for manufacturing a substrate for a monochrome liquid crystal display, wherein the filter is disposed in an outer peripheral opening. A method for manufacturing a multi-alignment division type vertical alignment mode liquid crystal display using the method for manufacturing a high / low pattern layer forming body according to any one of claims 1 to 3, wherein
The height pattern layer is an alignment control projection and a plurality of alignment division type vertical alignment columnar spacer used in the multiple alignment division type vertical alignment mode liquid crystal display,
The mask is a light-shielding layer that blocks transmission of light, a first opening formed along the pattern of the alignment control protrusions, and a second opening formed along the pattern of the columnar spacer for multiple alignment division type vertical alignment. 2. A method for manufacturing a multi-alignment division type vertical alignment mode liquid crystal display, comprising: two openings, wherein the filter is arranged at least in the first opening.

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