JP4163323B2 - LIQUID CRYSTAL DISPLAY DEVICE, ITS MANUFACTURING METHOD, SPACER DISTRIBUTION AND DISTRIBUTION METHOD, AND LIQUID CRYSTAL DISPLAY SPACER - Google Patents

Description

【００１７】
現像プロセスの要点は、静電潜像にトナーを忠実に早く、必要量付着させて鮮明で十分濃い印字を得ることである。さらに背景部にトナーの付着がないことも必要である。現像速度および付着トナー量は、現像領域での静電潜像の電場構造とトナー粒子の帯電電荷量とに依存する。
(4)の転写プロセスは、感光体ドラム２１の表面に形成されたトナー像に、記録紙２９を重ね、記録紙の裏側からコロナ帯電器でトナーの帯電極性とは逆極性の電荷を記録紙に与え、静電気力によりトナー像を記録紙に転写する工程である。転写に使用する力には、静電気力以外に、機械力および粘着力等がある。機械力を利用する圧力転写法では、記録紙と感光体間に圧力を加え、機械的に記録紙の繊維にトナーをすり込むことにより記録紙にトナーを転写する。粘着力を利用した粘着転写法では、感光体上のトナー像を粘着力で転写する。
【００１８】
感光体ドラム２１から記録紙２９へ転写されたトナーは弱い力でしか付着していないので簡単にはがれ落ちる。そのため、永久的に固着させることが必要である。(5)の定着プロセスは、転写されたトナー像に熱あるいは圧力を加え、記録紙に融着させて永久像とする工程である。
転写後の感光体ドラム２１上の潜像電荷は光により除電される。また、転写されずに感光体ドラム２１上に残った残留トナーはクリーナで除去される。この工程が(6)のクリーニングプロセスと除電プロセスである。
【００１９】
複写機では、以上の(1)〜(6)の一連のプロセスを繰り返すことにより連続的に印字を行う。
本発明では、上述した電子写真方式を用いた複写プロセスを、液晶表示装置におけるスペーサの分散配置へ応用することを基本とする。電子写真方式を用いてスペーサを分散配置する場合の、上述した記録紙への複写との相違点を具体的に述べながら、本発明について説明する。
【００２０】
スペーサを分散配置する場合には、まず液晶表示装置の電極基板上、あるいはカラーフィルタ上のどの位置に配置するのか決めなければならない。液晶表示装置のコントラスト向上や高表示品位の達成には画素領域すなわち表示領域にスペーサを分散配置するのは好ましくなく、非画素領域すなわち非表示領域にスペーサを分散配置することが好ましい。画素領域に分散配置されるとスペーサの存在部分が表示されず、スペーサ自身や、液晶の配向乱れによりスペーサ周囲は光抜けが発生するからである。したがって、例えば、ＴＮモードの場合には、文字や図案の周辺や間隙等、表示に直接かかわらない領域のみにスペーサを分散配置させることが好ましい。また、例えば、ＳＴＮモードの場合には、電極基板の透明電極がストライプ状に配列されているので、それらの透明電極の間隙にスペーサを分散配置させることが好ましい。また、例えば、ＴＦＴやＳＴＮのカラー表示の場合、カラーフィルタの画素のＲ、Ｇ、Ｂ以外の部分、すなわち、ブラックマトリクス上に分散配置させることが好ましい。また、カラーフィルタのある基板と対向した電極基板上に分散配置する場合は、ブラックマトリクスに対する位置へ分散配置させることが好ましい。
【００２１】
また、分散配置させるスペーサの位置の数は、液晶表示装置のセルギャップが均一に保持できれば特に限定はないが、少なすぎるとギャップの均一性が悪くなり、多すぎると低温発泡等が発生し易くなる。また、分散配置の数は表示領域の一つの画素の大きさによっても左右される。
以上のようにしてスペーサを分散配置させる位置を決定した後、上述した(1) の帯電プロセス、(2)の潜像形成プロセスを行って、感光体上に分散配置させたい位置の静電潜像を形成させる。
【００２２】
次に、(3)の現像プロセスでは、トナーの代わりに、後述のスペーサを用いて、上記で得られた静電潜像にスペーサを静電的に付着させる。スペーサの帯電方法としては、静電潜像へ正確に付着させるための帯電電荷量を付与させ易い摩擦帯電が好ましく、スペーサの保持・搬送手段としては、静電気力や磁力が好ましく、乾式現像法、特に二成分磁気ブラシ現像法や一成分絶縁トナー現像法の現像方式が好ましい。
【００２３】
(4)の転写プロセスでは、感光体表面に形成されたスペーサ像に電極基板やカラーフィルタを重ね、所定の位置、好ましくは非表示領域へ転写する。また、感光体表面に形成されたスペーサ像を一旦中間転写ベルトや他のフィルムへ転写して、更に再度電極基板やカラーフィルタへ転写してもよい。
(5)の定着プロセスでは、感光体から電極基板やカラーフィルタ上の所定の位置へ転写されたスペーサに、熱又は圧力を加え融着させて固定化する。加熱温度としては、スペーサに含まれるバインダーが溶融する温度以上、分解温度以下が好ましく、また、電極基板やカラーフィルタ上のスペーサ以外の部材へダメージを与えない温度であればよく、具体的には後述のスペーサの所で説明する。また、圧力としては、電極基板やカラーフィルタへダメージを与えない程度が好ましい。
【００２４】
(6)のクリーニングプロセスと除電プロセスは、感光体に残存する潜像や残留スペーサを除去するために必要であり、特に続けて他の電極基板やカラーフィルタ上へスペーサを連続的に分散配置する場合は必要である。
トナージェット方式は、上述したプロセスの内、(1)の帯電プロセス、(2)の潜像形成プロセス、(3)の現像プロセスを必要とせず、帯電したスペーサを直接電極基板やカラーフィルタ上の所定の位置へ定着させる方式である。また、一旦、他のフィルム等へスペーサを転写してから再度、電極基板やカラーフィルタへ転写してもよい。
本発明の液晶表示装置に用いられるスペーサについて説明する。
【００２５】
本発明ではスペーサは、電子写真方式により分散配置され得ることが必要であるため、いわゆるトナーとしての性質を有するものが使用される。本発明において好ましいスペーサは、固体微粒子とバインダー樹脂とを含み、帯電量が＋２〜＋５０μＣ／ｇ、または−５〜−５０μＣ／ｇのものである。より好ましくは、＋５〜＋３０μＣ／ｇ、または−７〜−３０μＣ／ｇである。帯電量の絶対値が小さい場合（＋２〜−５μＣ／ｇ）、スペーサを所定の位置へ分散配置することができなく、一方、帯電量の絶対値が大きい場合（−５０μＣ／ｇより負、＋５０μＣ／ｇより正）、スペーサ同士の静電凝集が生じてしまい、スペーサを分散配置した場合、所望の高さに調整できなかったり、高精度で分散配置できなくなる。スペーサの帯電量を上記範囲とするための方法は特に限定されるものではないが、後述するような電荷制御性のバインダー樹脂および／または電荷制御剤を用いることが好ましい。なお、ここでいう帯電量の測定は、ブローオフ法に基づいて行われる。ブローオフ帯電量測定装置としては、東芝ケミカル（株）製ＴＢ−２００等が市販されている。
【００２６】
上記固体微粒子の平均粒子径は、好ましくは１〜３０μｍ、より好ましくは１〜２０μｍ、最も好ましくは１〜１５μｍである。平均粒子径が上記範囲を外れると、スペーサーとして用いられないことがある。
上記固体微粒子の粒子径の変動係数（ＣＶ）は、好ましくは１０％以下、より好ましくは８％以下、さらに好ましくは６％以下である。粒子径の変動係数が１０％を超えると、液晶層の厚みを均一かつ一定に保持することが困難となり、画像ムラを起こしやすくなる。
【００２７】
上記固体微粒子の形状は、球状、針状、板状、鱗片状、破砕状、俵状、まゆ状、金平糖状等の任意の粒子形状で良く、特に限定されないが、液晶表示板の隙間距離を均一に一定とする上では球状が好ましい。これは、粒子が球状であると、すべてまたはほぼすべての方向について一定またはほぼ一定の粒径を有することができるからである。
【００２８】
上記固体微粒子としては、種々のものがあり、特に限定はされないが、たとえば、有機架橋重合体粒子、無機系粒子、有機質無機質複合体粒子等が挙げられる。これらの中でも、ビニル系架橋重合体粒子および有機質無機質複合体粒子が、電極基板、配向膜またはカラーフィルターの損傷防止や両電極基板間の隙間距離の均一性を得やすい点で好ましく、有機質無機質複合体粒子が最も好ましい。
【００２９】
前記有機架橋重合体粒子としては、特に限定はされないが、たとえば、ジビニルベンゼンを単独で重合あるいは他のビニル単量体と共重合させて得られるジビニルベンゼン架橋樹脂粒子（特開平１−１４４４２９号公報参照）等が挙げられる。
前記無機系粒子としては、特に限定はされないが、たとえば、ガラス、シリカ、アルミナ等の球状微粒子等が挙げられる。
【００３０】
前記有機質無機質複合体粒子は、有機質部分と無機質部分とからなる複合粒子である。この有機質無機質複合体粒子において、前記無機質部分の割合は、特に限定はされないが、たとえば、前記有機質無機質複合体粒子の重量に対して、無機酸化物換算で、好ましくは１０〜９０ｗｔ％、より好ましくは２５〜８５ｗｔ％、より好ましくは３０〜８０ｗｔ％の範囲である。無機質部分の割合を示す無機酸化物換算とは、有機質無機質複合体粒子を空気中などの酸化雰囲気中で高温（たとえば１０００℃）で焼成した前後の重量を測定することにより求めた重量百分率で示される。有機質無機質複合体粒子の無機質部分の割合が、無機酸化物換算で前記範囲を下回ると、有機質無機質複合体粒子が軟らかくなり、電極基板への散布個数が増えることがあり、また、前記範囲を上回ると、硬すぎて配向膜の損傷やＴＦＴの断線が生じやすくなることがある。
【００３１】
このような有機質無機質複合体粒子としては、特に限定はされないが、たとえば、有機ポリマー骨格と、前記有機ポリマー骨格中の少なくとも１個の炭素原子にケイ素原子が直接化学結合した有機ケイ素を分子内に有するポリシロキサン骨格とを含み、前記ポリシロキサン骨格を構成するＳｉＯ₂の量が１０ｗｔ％以上である、有機質無機質複合体粒子等を挙げることができる。有機ポリマー骨格としては、ビニル系ポリマーがギャップコントロールを制御できる高復元性を与えるため、好ましい。有機質無機質複合体粒子は、染料および／または顔料を含むことで着色されていてもよい。
【００３２】
有機質無機質複合体粒子の製造方法としては、特に限定されないが、たとえば、縮合工程と重合工程と熱処理工程とを含む下記の製造方法が挙げられる。
縮合工程は、ラジカル重合性基含有シリコン化合物を用いて加水分解・縮合する工程である。
ラジカル重合性基含有シリコン化合物は、次の一般式（１）：
【００３３】
【化１】

【００３４】
（ここで、Ｒ^aは水素原子またはメチル基を示し；Ｒ^bは、置換基を有していても良い炭素数１〜２０の２価の有機基を示し；Ｒ^cは、水素原子と、炭素数１〜５のアルキル基と、炭素数２〜５のアシル基とからなる群から選ばれる少なくとも１つの１価基を示す）
と、次の一般式（２）：
【００３５】
【化２】

【００３６】
（ここで、Ｒ^dは水素原子またはメチル基を示し；Ｒ^eは、水素原子と、炭素数１〜５のアルキル基と、炭素数２〜５のアシル基とからなる群から選ばれる少なくとも１つの１価基を示す）
と、次の一般式（３）：
【００３７】
【化３】

【００３８】
（ここで、Ｒ^fは水素原子またはメチル基を示し；Ｒ^gは、置換基を有していても良い炭素数１〜２０の２価の有機基を示し；Ｒ^hは、水素原子と、炭素数１〜５のアルキル基と、炭素数２〜５のアシル基とからなる群から選ばれる少なくとも１つの１価基を示す）
とからなる群から選ばれる少なくとも１つの一般式で表される化合物またはその誘導体であることが好ましい。
【００３９】
重合工程は、縮合工程中および／または縮合工程後に、ラジカル重合性基をラジカル重合反応させて粒子を得る工程である。
熱処理工程は、重合工程で生成した重合体粒子を好ましくは８００℃以下、より好ましくは６００℃以下の温度で乾燥および焼成する工程である。熱処理工程は、たとえば、１０容量％以下の酸素濃度を有する雰囲気中や減圧下で行われることが好ましい。
【００４０】
縮合工程、重合工程および熱処理工程から選ばれる少なくとも１つの工程中および／または後に、生成した粒子を着色する着色工程をさらに含んでいてもよい。
上記固体微粒子は、染料および顔料からなる群から選ばれる少なくとも１つ等を含むことで着色されていてもよい。その色は、光が透過しにくいか、または、透過しない色が、スペーサー自身の光抜けを防止でき画質のコントラストを向上できる点で好ましい。光が透過しにくいか、または、透過しない色としては、たとえば、黒、濃青、紺、紫、青、濃緑、緑、茶、赤等の色が挙げられるが、特に好ましくは、黒、濃青、紺色である。
【００４１】
なお、染料および／または顔料は、単に固体微粒子に含まれるものでもよく、あるいは、染料および／または顔料と粒子本体を構成するマトリックスとが化学結合によって結び付けられた構造を有するものでもよい。
上記バインダー樹脂としては、エチレン性不飽和単量体の単独重合体または共重合体、ポリエステル樹脂、エポキシ樹脂等が挙げられる。これらのバインダー樹脂は、１種のみ用いてもよいし、２種以上を併用してもよい。
【００４２】
エチレン性不飽和単量体の単独重合体または共重合体の原料となるエチレン性不飽和単量体としては、特に限定はされないが、たとえば、ビニルエステル系単量体（酢酸ビニル等）、ビニル芳香族系単量体（スチレン、ビニルトルエン、α−メチルスチレン、α−クロロスチレン、ビニルナフタレン、ビニルキシレン等）、（メタ）アクリル系単量体（（メタ）アクリル酸、メチル（メタ）アクリレート、エチル（メタ）アクリレート、ｎ−プロピル（メタ）アクリレート、イソプロピル（メタ）アクリレート、ブチル（メタ）アクリレート、ヘキシル（メタ）アクリレート、２−エチルヘキシル（メタ）アクリレート、ラウリル（メタ）アクリレート、シクロヘキシル（メタ）アクリレート等）、共役ジオレフィン系単量体（ブタジエン、イソブチレン、クロロプレン等）、エチレン性不飽和カルボン酸（フマル酸、無水マレイン酸等）等が挙げられる。これらの中でも、（メタ）アクリル酸エステルおよびスチレンが、定着性が高いため好ましい。
【００４３】
前記バインダー樹脂としては、定着性をより向上させる観点から、エチレン性不飽和単量体の単独重合体または共重合体が好ましく、中でも（メタ）アクリル系樹脂および（メタ）アクリル−スチレン系樹脂からなる群の中から選ばれた少なくとも１種が最も好ましい。
バインダー樹脂のガラス転移温度は、好ましくは４０〜１００℃、より好ましくは４５〜９０℃、さらに好ましくは５０〜８０℃である。ガラス転移温度が４０℃未満では、スペーサが貯蔵中に融着等を起こしたり、電極基板上に分散配置する際の分散性が悪くなる場合がある。一方、ガラス転移温度が１００℃を超えると、分散配置させる際の加熱又は加圧時に、バインダー樹脂が溶融しにくく、そのため、電極基板やカラーフィルタへの定着性が不充分となる場合がある。
【００４４】
バインダー樹脂の軟化温度は、好ましくは５０〜１６０℃、より好ましくは６０〜１５０℃、さらに好ましくは７０〜１４０℃である。軟化温度が５０℃未満では、スペーサが貯蔵中に融着等を起こしたり、電極基板上に分散配置する際の分散性が悪くなる場合がある。一方、軟化温度が１６０℃を超えると、分散配置させる際の加熱又は加圧時に、バインダー樹脂が溶融しにくく、そのため、電極基板やカラーフィルタへの定着性が不充分となる場合がある。
【００４５】
一般にバインダー樹脂は、塩基性窒素等の電子供与性の置換基を含むものは正帯電性を示し、塩素、フッ素等の電子受容性の置換基を含むものは負帯電性を示す。例えば、ポリエステル樹脂は負帯電性が強く、（メタ）アクリル系樹脂やスチレン／（メタ）アクリル系樹脂は中性から弱い負帯電性を示す。
本発明においてバインダー樹脂としては電荷制御性を示すものが好ましく、負帯電性としては、ポリエステル樹脂、（メタ）アクリル酸等の酸基を導入した（メタ）アクリル系樹脂やスチレン／（メタ）アクリル系樹脂が好ましい。正帯電性としては、ジメチルアミノエチルメタクリレート等の窒素を導入した（メタ）アクリル系樹脂やスチレン／（メタ）アクリル系樹脂が好ましい。
【００４６】
また、バインダー樹脂全体の２〜２０重量％の割合で、低分子量ポリプロピレン、低分子量ポリエチレン等の低分子量オレフィン樹脂、パラフィンワックス、カルナバロウ等の各種ワックスをオフセット防止剤として加えることも可能である。
バインダー樹脂は、染料および顔料からなる群から選ばれる少なくとも１つ等を含むことで着色されていてもよい。その色は、光が透過しにくいか、または、透過しない色が、光抜けを防止でき画質のコントラストを向上できる点で好ましい。光が透過しにくいか、または、透過しない色としては、たとえば、黒、濃青、紺、紫、青、濃緑、緑、茶、赤等の色が挙げられるが、特に好ましくは、黒、濃青、紺色である。
【００４７】
バインダー樹脂の着色に使用できる染料および顔料としては、特に限定はされない。
固体微粒子に対するバインダー樹脂の重量割合は、特に限定はされないが、好ましくは１〜２００％、より好ましくは３〜１００％、特に好ましくは５〜５０％である。バインダー樹脂の重量割合が２００％を超えると、樹脂分が多くなって、溶融した際にスペーサの分散配置の面積が大きくなり、液晶表示板の表示領域へスペーサを分散配置したり、非表示領域へ分散配置しても表示領域まで被覆して、液晶表示板の画質低下を招く恐れがある。一方、バインダー樹脂の重量割合が少ないと、定着性が低下する。
【００４８】
上記バインダー樹脂は固体微粒子表面に存在していることが好ましく、固体微粒子表面の少なくとも一部を被覆するものであってもよいし、固体微粒子表面と化学結合していてもよい。
その場合のバインダー樹脂層の厚みは、特に限定はされないが、通常、０．０１〜５μｍの範囲、好ましくは０．０５〜２μｍの範囲である。厚みが上記範囲より小さいと、定着性が低下するおそれがあり、また、厚みが上記範囲より大きいと、スペーサの分散配置の面積が広くなって、液晶表示板の表示領域へスペーサを分散配置したり、非表示領域へ分散配置しても表示領域まで被覆して、液晶表示板の表示品位が低下するおそれがある。
【００４９】
バインダー樹脂層が固体微粒子表面に存在している場合の平均粒子径（固体微粒子本体にバインダー樹脂層の厚みが付与されたものの平均粒子径）は特に限定されないが、好ましくは１．５〜２５μｍ、より好ましくは２〜２５μｍ、さらに好ましくは２．５〜１７μｍである。
固体微粒子をバインダー樹脂で被覆する方法、もしくは固体微粒子表面とバインダー樹脂とを化学結合させる方法としては、特に限定はされないが、たとえば、バインダー樹脂の溶液中に、固体微粒子を分散させ、充分攪拌混合した後、溶剤を蒸発除去し、得られた塊状物を粉砕する方法や、溶融させたバインダー樹脂中に、固体微粒子を分散させ、混練して充分に分散させ、冷却後に塊状物を粉砕する方法；固体微粒子表面に各種官能基（ビニル基、エポキシ基、水酸基等）を導入し、その官能基を起点としてモノマーを重合させたり、その官能基とポリマーとを反応させて、粒子表面にグラフトさせる方法等がある。
【００５０】
また、上記方法以外に、「表面の改質」（日本化学会編化学総説No.44 、第45〜52頁、1987年発行）や「粉体の表面改質と高機能化技術」（「表面」第25巻第１号第１〜19頁および表紙写真、1987年発行）に詳細に記載されている、Ｉｎ ｓｉｔｕ重合法、コアセルベーション法、界面重合法、液中硬化被覆法、液中乾燥法、高速気流中衝撃法、気中懸濁被覆法、スプレードライング法等の従来公知の樹脂被覆方法によっても、被覆することができる。特に、高速気流中衝撃法は、たとえば、固体微粒子と、バインダー樹脂の粉体とを混合し、この混合物を気相中に分散させ、衝撃力を主体とする機械的熱的エネルギーを前記粒子と前記バインダー樹脂粉体とに与えることで、前記粒子の表面を前記バインダー樹脂で被覆する方法であり、簡便に被覆することができるので、最も好ましい。この高速気流中衝撃法を行う際に用いられる前記バインダー樹脂粉体の平均粒子径は、特に限定はされないが、たとえば、好ましくは２μｍ以下、より好ましくは１．８μｍ以下、最も好ましくは１μｍ以下である。
【００５１】
上記高速気流中衝撃法を利用した装置としては、特に限定はされないが、たとえば、奈良機械製作所（株）製ハイブリダイゼーションシステムや、ホソカワミクロン（株）製メカノフュージョンシステム、川崎重工業（株）製クリプトロンシステム等がある。
上述したように本発明のスペーサは、さらに電荷制御剤を含むことができる。電荷制御剤としては、特に限定されず、有機物であっても無機物であってもよい。正帯電性を示すものとしては、電子供与性物質であり、例えば、有機物では、ニグロシン染料等の塩基性染料、第４級アンモニウム化合物、脂肪酸金属塩、ベンゾグアナミン系樹脂等、無機物では、アミノ基で表面処理した（疎水性）シリカ、（疎水性）チタニア等がある。負帯電性を示すものとしては、電子受容性物質であり、例えば、有機物では、アゾ系含金属染料、サリチル酸誘導体の金属錯体、塩素化パラフィン、塩素化ポリエステル等、無機物では（疎水性）シリカ等がある。
【００５２】
電荷制御剤の量は、特に限定されないが、バインダー樹脂に対して０．０１〜２０重量％が好ましく、より好ましくは０．５〜１５重量％、さらに好ましくは１〜１０重量％である。電荷制御剤の量が多すぎても少なすぎても、スペーサの帯電量が上述の範囲に入らなくなる。
さらに本発明のスペーサは、上記以外の添加剤として、フェライト系の磁性体、シリカ等の外添剤、酸化防止剤、離型剤等を必要に応じて含んでいても良い。
【００５３】
本発明の液晶表示装置において、スペーサ以外の、電極基板、シール材、液晶材料などについては従来と同様のものを従来と同様に使用することができる。
電極基板は、ガラス基板、フィルム基板などの基板と、基板の表面に形成された電極とを有しており、必要に応じて、電極基板の表面に電極を覆うように形成された配向膜をさらに有する。また、カラー対応の液晶表示装置の場合、カラーフィルタを有する。シール材としては、エポキシ樹脂接着シール材などが使用される。液晶としては、従来より用いられているものでよく、たとえば、ビフェニル系、フェニルシクロヘキサン系、シッフ塩基系、アゾ系、アゾキシ系、安息香酸エステル系、ターフェニル系、シクロヘキシルカルボン酸エステル系、ビフェニルシクロヘキサン系、ピリミジン系、ジオキサン系、シクロヘキシルシクロヘキサンエステル系、シクロヘキシルエタン系、シクロヘキセン系、フッ素系などの液晶が使用できる。
【００５４】
本発明の液晶表示装置を製造する方法としては、たとえば、面内スペーサを２枚の電極基板のうちの一方の電極基板に電子写真方式により所定の位置に分散配置したものの上に、エポキシ樹脂等の接着シール材にシール部スペーサを分散させたものをもう一方の電極基板の接着シール部分にスクリーン印刷などの手段により塗布したものを載せ、適度の圧力を加え、１００〜１８０℃の温度で１〜６０分間の加熱、または、照射量４０〜３００ｍＪ／cm²の紫外線照射により、接着シール材を加熱硬化させた後、液晶を注入し、注入部を封止する方法を挙げることができるが、これに限定されるものではない。
【００５５】
本発明の液晶表示装置は、従来の液晶表示装置と同じ用途、たとえば、テレビ、モニター、パーソナルコンピューター、ワードプロセッサー、カーナビゲーションシステム、ＤＶＤ、デジタルビデオカメラ、ＰＨＳ（携帯情報端末）などの画像表示素子として使用される。
【００５６】
【実施例】
以下に実施例によりさらに詳細に本発明を説明するが、本発明はこれに限定されるものではない。
実施例中で「部」、「％」とは特にことわりがない限り、それぞれ「重量部」、「重量％」を表すものとする。
＜固体微粒子の平均粒子径、粒子径の変動係数＞
固体微粒子を電子顕微鏡により観察して、その撮影像の任意の粒子２００個の粒子径を実測し、次式に従って、平均粒子径、粒子径の標準偏差および粒子径の変動係数を求めた。
【００５７】
【数１】

【００５８】
【数２】

【００５９】
【数３】

【００６０】
＜バインダー樹脂のガラス転移温度＞
パーキンエルマー社製のＤＳＣ−７を用いて測定した。
＜バインダー樹脂の軟化温度＞
島津製作所製フローテスタＣＦＴ−５００Ｃ型を用いて、以下の条件で昇温法により測定し、流出開始温度を軟化温度とした。
【００６１】
開始温度：室温
終了温度：２３０℃
昇温速度：６℃／分
試験荷重：２０．０ｋｇｆ
ダイ穴径：０．５０ｍｍ
ダイ長さ：１．００ｍｍ
＜バインダー樹脂の平均粒子径＞
上記固体微粒子の平均粒子径の測定方法に準じた。
＜スペーサの帯電量＞
ブローオフ法に基づき、鉄粉（同和鉄粉（株）製ＤＳＰ−１２８）とスペーサを２５℃、６０％ＲＨ中で２４時間放置後、鉄粉２８．５０ｇとスペーサ１．５０ｇをボトル中で１分間混合した後、ブローオフ帯電量測定機（東芝ケミカル（株）製ＴＢ−２００）にて測定した。
＜固体微粒子の合成例＞
冷却管、温度計、滴下口のついた四つ口フラスコ中に２５％アンモニア水溶液４．５ｇ、水３８７．３ｇを混合した溶液（Ａ液）を入れ、２５±２℃に保持し、攪拌しながら該溶液中に、γ−メタクリロキシプロピルトリメトキシシラン６２ｇ、ビニルトリメトキシシラン２８ｇ、テトラエトキシシランの四〜五量体５ｇ、ラジカル重合開始剤として２，２′−アゾビス−（４−メトキシ−２，４−ジメチルバレロニトリル）０．３４ｇを混合した溶液（Ｂ液）を滴下口から添加して、γ−メタクリロキシプロピルトリメトキシシランと、ビニルトリメトキシシランと、テトラエトキシシランの四〜五量体との共加水分解・重縮合を行った。攪拌を継続しながら２０分後、Ｎ₂雰囲気中で６０±５℃に加熱し、ラジカル重合を行った。
【００６２】
２時間加熱を続けた後、室温まで冷却し、重合体粒子の懸濁体を得た。この懸濁体を濾過により固液分離し、得られたケーキをメタノールによるデカンテーションで３回洗浄した。
洗浄したケーキを濾過し、得られた粒子を窒素雰囲気中で３００℃で２時間焼成して球状の固体微粒子（１）を得た。
【００６３】
得られた固体微粒子（１）は、有機質無機質複合体であり、平均粒子径５．７μｍ、粒子径の変動係数３．５％、ポリシロキサン骨格の割合が固体微粒子（１）の重量に対してＳｉＯ₂換算量で４６．０ｗｔ％であった。
＜バインダー樹脂の合成例＞
バインダーとして表２に示すモノマー組成からなる樹脂をソープフリー重合で合成した。表２にガラス転移温度、軟化温度、平均粒子径もあわせて示した。
【００６４】
【表２】

【００６５】
［実施例１］
固体微粒子として、合成例で得られた固体微粒子（１）３５ｇと、バインダー（１）１４ｇ、負帯電用の電荷制御剤として下記化学式で示されるアゾ染料金属錯体（ただし、Ｍ＝Ｃｒ、Ｒ１＝Ｒ３＝Ｃｌ、Ｒ２＝Ｒ４＝Ｈ）０．２ｇ、低分子量ポリプロピレン０．５ｇとを混合した後、奈良機械製作所（株）製ハイブリダイゼーションシステムＮＨＳ−０型を使用して高速気流中衝撃法により固体微粒子（１）の表面をバインダー（１）で被覆処理して接着性粒子（１）を得た。該接着性粒子（１）のバインダー中には、電荷制御剤と低分子量ポリプロピレンが含有されていた。
【００６６】
【化４】

【００６７】
次に外添剤として疎水性シリカ超微粒子（日本アエロジル（株）製アエロジルＲ９７２、平均粒子径１６ｎｍ）０．０７ｇをコーヒーミル中で１０秒間攪拌した後、上記で得られた接着性粒子（１）３５ｇを添加して２０秒間攪拌混合し、接着性粒子（１）の表面に外添剤を付着させてスペーサ（１）を得た。
得られたスペーサ（１）は平均粒子径６．３μｍ、帯電量が−２６μＣ／ｇであった。
［実施例２］
実施例１において、バインダー（１）の代わりに負帯電性を示す電荷制御性のバインダー（２）を用い、アゾ染料金属錯体からなる電荷制御剤を使用せずに、その他は実施例１と同様にして、スペーサ（２）を得た。
【００６８】
得られたスペーサ（２）は平均粒子径６．２μｍ、帯電量が−１８μＣ／ｇであった。
［実施例３］
実施例１において、電荷制御剤としてアゾ染料金属錯体の代わりに正帯電性の電荷制御剤であるニグロシン０．２ｇを用い、疎水性シリカ超微粒子からなる外添剤を使用せずに、その他は実施例１と同様にして、スペーサ（３）を得た。
【００６９】
得られたスペーサ（３）は平均粒子径６．４μｍ、帯電量が＋１５μＣ／ｇであった。
［比較例１］
実施例１において、電荷制御剤を用いずに、その他は実施例１と同様にして、比較スペーサ（１）を得た。
【００７０】
得られた比較スペーサ（１）は平均粒子径６．４μｍ、帯電量が−２μＣ／ｇであった。
［比較例２］
実施例１において、アゾ染料金属錯体からなる電荷制御剤の量を３．０ｇとした以外は実施例１と同様にして、比較スペーサ（２）を得た。
【００７１】
得られた比較スペーサ（２）は平均粒子径６．１μｍ、帯電量が−７４μＣ／ｇであった。
［比較例３］
実施例３において、ニグロシンからなる電荷制御剤の量を３．０ｇとした以外は実施例３と同様にして、比較スペーサ（３）を得た。
【００７２】
得られた比較スペーサ（３）は平均粒子径６．５μｍ、帯電量が＋６７μＣ／ｇであった。
［実施例４］
ＴＦＴ型液晶表示装置において、カラーフィルタが設置されている電極基板のカラーフィルタのブラックマトリクス上に７０μｍおきにスペーサを分散配置するためにまずスペーサを分散配置すべきパターンを作製した。
【００７３】
次に図２に示すようなカールソン法からなる電子写真方式を用い、カラーフィルタ上のブラックマトリクス上にスペーサを固定化して、カラーフィルタのブラックマトリクス上にスペーサを分散配置した。すなわち、まず前記パターンを感光体上に静電潜像として形成させ、次いで、実施例１で得られたスペーサ（１）を前記静電潜像へ付着させ、カラーフィルタが設置された電極基板へ転写した後、１５０℃で加熱して定着させた。スペーサはブラックマトリクス上の所定の位置に７０μｍおきに分散配置されており、分散配置の密度は２０４個／ｍｍ²であった。
【００７４】
次に以下の手順でＴＦＴ型液晶表示装置を作製した。ＴＦＴ素子を有する透明電極基板と、上記のようにしてスペーサが分散配置されたカラーフィルタを有する透明電極基板とを、接着シール材で貼り合わせ、その後両電極基板の隙間を真空として更に大気圧に戻すことによりＴＦＴ用フッ素系ＴＮ液晶を注入し、注入部を封止した。そして、上下電極基板の外側に偏光フィルムを貼り、ＴＦＴ型液晶表示装置（１）を得た。
【００７５】
得られた液晶表示装置（１）は、色ムラがないものであった。これから、液晶表示装置（１）はギャップ均一性が優れたものであり、スペーサの分散配置が高精度で行われて高さにばらつきのないことがわかる。また、液晶表示装置（１）はコントラストが高く、ザラツキのないものであった。これから、スペーサが表示領域には存在しないことがわかる。以上のように、液晶表示装置（１）は良好な表示品位を示した。これらの結果を表３，４に示す。
［実施例５，６］
実施例４において、静電潜像へ付着させるスペーサとしてスペーサ（１）の代わりに、実施例２，３で得られたスペーサ（２），（３）を用いた以外は、実施例４と同様にしてＴＦＴ型液晶表示装置（２），（３）を得た。その結果を表３，４に示す。
［実施例７］
実施例４において、スペーサの分散配置方法をカールソン法からトナージェット法に変更した以外は、実施例４と同様にしてＴＦＴ型液晶表示装置（４）を得た。その結果を表３，４に示す。
［比較例４〜６］
実施例４において、静電潜像へ付着させるスペーサとしてスペーサ（１）の代わりに、比較例１〜３で得られた比較スペーサ（１）〜（３）を用いた以外は、実施例４と同様にして比較ＴＦＴ型液晶表示装置（１）〜（３）を得た。その結果を表３，４に示す。
［比較例７］
実施例４において、スペーサの分散配置方法を電子写真法式から、従来から用いられている高速気流式の乾式散布法に変更した以外は、実施例４と同様にして比較ＴＦＴ型液晶表示装置（４）を得た。スペーサの散布には、日清エンジニアリング（株）製ＤＩＳＰＡ−μＲを用い、散布個数は約２００±２０個／ｍｍ²とした。その結果を表３，４に示す。
【００７６】
【表３】

【００７７】
【表４】

【００７８】
【発明の効果】
本発明によると、スペーサの非表示領域への正確な分散配置と、所望の高さへの調整が容易かつ簡便にでき、その結果、コントラストの低下、ざらつき、色むら等がなく、表示品位に非常に優れた液晶表示装置を得ることができる。
【図面の簡単な説明】
【図１】本発明の液晶表示装置の一例を表わす概略断面図である。
【図２】電子写真方式の基本構成を表わす図である。
【図３】正現像法と反転現像法を示す図である。
【符号の説明】
２ シール材
３ シール部スペーサー
４ 配向膜
５ 電極
６ 偏光膜
７ 液晶
８ 面内スペーサー
１１ 下側ガラス基板
１２ 上側ガラス基板
２１ 感光体ドラム
２２ 帯電器
２３ 露光器
２４ 現像器
２５ 転写器
２６ 定着器
２７ 除電器
２８ クリーナ
２９ 記録紙
１１０ 下側電極基板
１２０ 上側電極基板[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a liquid crystal display device, a method for manufacturing the same, a method for dispersing and arranging spacers, and a spacer for a liquid crystal display panel.
[0002]
[Prior art]
Conventionally, when manufacturing an LCD, the spacers are sprayed on the substrate by wet or dry spraying. However, since the spacers are dispersedly arranged on the pixels, the existing portions of the spacers are not displayed, and the light from the backlight passes through the spacers themselves or around the spacers due to disorder of the alignment of the liquid crystal. As a result, there has been a problem that the display quality is greatly lowered due to a decrease in the contrast and roughness of the LCD.
[0003]
Therefore, a method of arranging spacers in a non-display area other than pixels and a method of forming columnar spacers on a black matrix of a color filter are known.
As a method of arranging the spacer, a method of causing the spacer to exist on the black matrix by mixing the spacer with a photoresist and performing exposure and development processing by a photolithography technique (Japanese Patent Laid-Open No. 9-160009), at the time of liquid crystal injection There are known a method of moving a spacer to a non-pixel region by utilizing the flow of a liquid (Japanese Patent Laid-Open No. 10-68952), a method of adhering to a substrate by electrophoresis (Japanese Patent Laid-Open No. 10-104638), and the like. .
[0004]
On the other hand, as a method of forming columnar spacers on a black matrix, a method of forming columnar spacers made of a photosensitive resin by a photolithography technique is known (Japanese Patent Laid-Open No. 10-73827).
[0005]
[Problems to be solved by the invention]
However, in the method using the photolithography technique, the process is complicated, and it is difficult to adjust to a desired height. On the contrary, nonuniformity of gaps is likely to occur, and color unevenness is likely to occur. There is also a problem. In addition, it is difficult for other methods to accurately disperse and arrange the spacers in the non-pixel regions.
[0006]
Therefore, an object of the present invention is to solve these conventional problems at once, and the accurate dispersion arrangement of the spacers in the non-display area and the adjustment to the desired height can be easily and easily performed. An object of the present invention is to provide a liquid crystal display device having no reduction in contrast, roughness, color unevenness, etc., and excellent display quality, a method for manufacturing the same, a method for dispersing and arranging spacers, and a spacer for a liquid crystal display panel.
[0007]
[Means for Solving the Problems]
In order to solve the above problems, the present invention provides the following configurations.
(1) A liquid crystal display device comprising: a pair of electrode substrates disposed opposite to each other with a liquid crystal material interposed therebetween; and a spacer that is selectively distributed between the electrode substrates and maintains a distance between the electrode substrates. The liquid crystal display device is characterized in that the spacers are dispersedly arranged at predetermined positions using an electrophotographic system.
(2) A method for manufacturing a liquid crystal display device, comprising: a pair of electrode substrates arranged to face each other with a liquid crystal material interposed therebetween; and spacers that are selectively distributed between the electrode substrates and maintain a distance between the electrode substrates. The method of manufacturing a liquid crystal display device according to claim 1, wherein the spacers are dispersedly arranged at predetermined positions using an electrophotographic method.
(3) A method for dispersing and arranging spacers on a substrate, the spacers being arranged at predetermined positions using an electrophotographic method.
(4) A spacer for a liquid crystal display panel for dispersive arrangement using an electrophotographic method, comprising solid fine particles and a binder resin, and having a charge amount of +2 to +50 μC / g or −5 to −50 μC / g A spacer for a liquid crystal display panel, characterized in that
[0008]
DETAILED DESCRIPTION OF THE INVENTION
The configuration of the liquid crystal display device of the present invention will be described with reference to FIG.
The liquid crystal display device of the present invention includes a pair of electrode substrates (a first electrode substrate 110 and a second electrode substrate 120) arranged to face each other with a liquid crystal material interposed therebetween, and a spacer. The first electrode substrate 110 includes a first substrate 11 and an electrode 5 formed on the surface of the first substrate 11. The second electrode substrate 120 includes the second substrate 12 and the electrode 5 formed on the surface of the second substrate 12. The first electrode substrate 110 and the second electrode substrate 120 are bonded together by the sealing material 2 at the periphery thereof. The spacers are selectively distributed between the substrates to maintain the distance between the substrates, and there are seal portion spacers 3 dispersed in the sealing material 2 and in-plane spacers 8 dispersed in the surface. To do. The liquid crystal material 7 is sealed between the first electrode substrate 110 and the second electrode substrate 120, and is filled in a space surrounded by the first electrode substrate 110, the second electrode substrate 120, and the sealing material 2. Yes.
[0009]
The present invention is characterized in that spacers (mainly in-plane spacers) are dispersedly arranged at predetermined positions using an electrophotographic system. The electrophotographic method forms an electrostatic latent image on the surface of a photoreceptor or an insulator, develops the latent image by applying a developer, and transfers the obtained image to a transfer member as necessary. This is a method of fixing and obtaining a transfer product. According to the electrophotographic method, the spacers can be accurately dispersed and arranged, and the adjustment to the desired height is very simple, so that there is no problem of gap non-uniformity which is a problem in the photolithography method.
[0010]
Various methods are known for electrophotography, such as the Carlson method, PIP (persistent internal polarization method, photoelectret method), charge transfer method, light injection method, electroelectrophotography, ion flow method, barrier modulation method. Organic Memory Coating (OMC), particle transfer method, photoelectrophoresis, EPM (Electro-Plate Marking), photothermoplastic recording, γ-luticon, toner jet method, etc. The toner jet method is particularly preferable.
[0011]
In the Carlson method, a uniform charge (−10 to 10 μm) is applied to the surface of an insulating photoconductor layer (thickness of 100 μm or less) by corona discharge. ⁷ C / cm ² ), And then the charge in the exposed area is eliminated by light to obtain an electrostatic latent image, which is then developed with toner, and transferred and fixed to a transfer object. The toner jet method is a system in which toner is ejected from a control electrode array onto a transfer object and fixed from the back side of the transfer object through a reverse electrode. With a simple structure that does not require a light source and drums, it is possible to reduce the size and price of a crisis. According to these methods, it is possible to easily design a predetermined position (for example, a non-display area (such as a black matrix of a color filter) in a liquid crystal display device) where the spacers are to be dispersedly arranged, and to achieve the predetermined position with high accuracy. The spacers can be easily distributed and arranged.
[0012]
The electrophotographic method, particularly the Carlson method, is a technique widely used in copying machines, and the copying process will be described first.
As shown in FIG. 2, the basic configuration of the electrophotographic system includes a photosensitive drum 21, a charger 22, an exposure device 23, a developing device 24, a transfer device 25, a fixing device 26, a static eliminator 27, and a cleaner 28. Yes. The copying process will be described using the configuration of the copying machine of FIG. The electrophotographic process basically consists of (1) charging process, (2) latent image formation process, (3) development process, (4) transfer process, (5) fixing process, (6) cleaning process and static elimination process. Is done.
[0013]
The charging process (1) is a process in which ions or electrons are attached to the surface of the photosensitive drum 21 using the charger 22 and uniformly charged to a constant potential. The charging method is roughly classified into a non-contact charging method and a contact charging method. As a non-contact charging method, corona charging is generally used. On the other hand, the contact charging method includes conductive brush charging and conductive roller charging.
[0014]
The latent image forming process (2) is a process of forming an electrostatic latent image on the photosensitive drum 21 using the photoconductive phenomenon using the exposure device 23. There are two types of latent images: a positive latent image that irradiates light outside the image area, removes the charged charges in the irradiated area, and leaves a charge in the image area. There are only negative latent images that remove charged charges.
[0015]
The development process (3) is a step in which a toner, which is a charged colored charged fine particle, is electrostatically attached to the electrostatic latent image formed on the surface of the photosensitive drum 21 so that development is possible.
The electrostatic latent image developing method includes a normal developing method and a reversal developing method as shown in FIG. The forward development method is a method in which toner having a charge opposite in polarity to the latent image charge is electrostatically attached. On the other hand, the reversal development method is a method in which an electric field is formed with the help of a developing electrode at a place where charge has been removed, and a toner charged with the same polarity as that of a uniform charge is attached by this electric field. Development is performed by three processes: (1) charging of toner particles, (2) transport of charged toner to the development area, and (3) toner adhesion to the electrostatic latent image. The developer or developing member charged by the movement of the toner is then neutralized and returns to the initial state. There are three main toner charging methods: friction charging, charge injection charging based on charge injection from the developing electrode, and electrophoretic charging in a liquid. Examples of toner holding / conveying means include electrostatic force, magnetic force, gravity, liquid flow, and air flow. Various developing methods are used by combining these toner charging methods and toner holding / conveying means. A typical example is shown in Table 1.
[0016]
[Table 1]

[0017]
The main point of the development process is to obtain a clear and sufficiently dark print by attaching a required amount of toner to the electrostatic latent image quickly and accurately. Further, it is necessary that the toner does not adhere to the background portion. The developing speed and the amount of adhered toner depend on the electric field structure of the electrostatic latent image in the developing area and the charged amount of toner particles.
In the transfer process (4), the recording paper 29 is superimposed on the toner image formed on the surface of the photosensitive drum 21, and a charge opposite in polarity to the charging polarity of the toner is applied to the recording paper from the back side of the recording paper with a corona charger. The toner image is transferred to the recording paper by electrostatic force. The force used for transfer includes mechanical force and adhesive force in addition to electrostatic force. In the pressure transfer method using mechanical force, pressure is applied between the recording paper and the photosensitive member, and the toner is transferred onto the recording paper by mechanically rubbing the toner into the fibers of the recording paper. In the adhesive transfer method using adhesive force, the toner image on the photoconductor is transferred with adhesive force.
[0018]
Since the toner transferred from the photosensitive drum 21 to the recording paper 29 is attached only with a weak force, it easily peels off. Therefore, it is necessary to fix it permanently. The fixing process (5) is a step of applying heat or pressure to the transferred toner image and fusing it to a recording paper to obtain a permanent image.
The latent image charge on the photosensitive drum 21 after the transfer is neutralized by light. Further, the residual toner which is not transferred and remains on the photosensitive drum 21 is removed by a cleaner. This process is the cleaning process (6) and the static elimination process.
[0019]
In the copying machine, printing is continuously performed by repeating the series of processes (1) to (6).
In the present invention, the copying process using the above-described electrophotographic method is basically applied to a spacer spacer arrangement in a liquid crystal display device. The present invention will be described while specifically describing the differences from the above-described copying on recording paper when spacers are dispersedly arranged using an electrophotographic system.
[0020]
When the spacers are dispersedly arranged, it is first necessary to determine at which position on the electrode substrate of the liquid crystal display device or the color filter. In order to improve the contrast of the liquid crystal display device and achieve high display quality, it is not preferable to disperse the spacers in the pixel region, that is, the display region, and it is preferable to disperse the spacers in the non-pixel region, that is, the non-display region. This is because when the pixel area is dispersedly arranged, the existence portion of the spacer is not displayed, and light escape occurs around the spacer due to the alignment of the spacer itself or the liquid crystal. Therefore, for example, in the case of the TN mode, it is preferable to disperse the spacers only in the areas that are not directly related to the display, such as the periphery of characters and designs and gaps. Further, for example, in the STN mode, since the transparent electrodes of the electrode substrate are arranged in stripes, it is preferable to disperse spacers in the gaps between the transparent electrodes. Further, for example, in the case of color display of TFT or STN, it is preferable to disperse and arrange on the portion other than R, G, B of the pixel of the color filter, that is, the black matrix. Further, in the case of dispersively arranging on the electrode substrate facing the substrate with the color filter, it is preferable to disperse and arrange at positions relative to the black matrix.
[0021]
In addition, the number of spacer positions to be dispersed is not particularly limited as long as the cell gap of the liquid crystal display device can be maintained uniformly. However, if the amount is too small, the uniformity of the gap is deteriorated. Become. The number of dispersed arrangements also depends on the size of one pixel in the display area.
After determining the positions where the spacers are dispersedly arranged as described above, the electrostatic latent image at the positions where the spacers are desired to be dispersedly arranged on the photosensitive member is performed by performing the above-described charging process (1) and latent image forming process (2). Form an image.
[0022]
Next, in the development process (3), a spacer is electrostatically attached to the electrostatic latent image obtained above using a spacer described later instead of the toner. As a method for charging the spacer, frictional charging that easily imparts a charge amount for accurately attaching to the electrostatic latent image is preferable, and as a means for holding and transporting the spacer, electrostatic force or magnetic force is preferable, dry development method, In particular, a two-component magnetic brush developing method or a one-component insulating toner developing method is preferable.
[0023]
In the transfer process (4), an electrode substrate and a color filter are superimposed on the spacer image formed on the surface of the photoreceptor, and transferred to a predetermined position, preferably a non-display area. Alternatively, the spacer image formed on the surface of the photoreceptor may be once transferred to an intermediate transfer belt or other film, and further transferred to the electrode substrate or the color filter again.
In the fixing process (5), heat or pressure is applied to the spacer transferred from the photosensitive member to a predetermined position on the electrode substrate or color filter, and the spacer is fixed by fusion. The heating temperature is preferably higher than the temperature at which the binder contained in the spacer melts and lower than the decomposition temperature, and may be any temperature that does not damage members other than the spacer on the electrode substrate or color filter. This will be described in the place of a spacer described later. Further, the pressure is preferably such that the electrode substrate and the color filter are not damaged.
[0024]
The cleaning process and charge removal process of (6) are necessary to remove the latent image remaining on the photoconductor and the remaining spacers. In particular, the spacers are continuously dispersed and arranged on other electrode substrates and color filters. If necessary.
The toner jet method does not require the charging process (1), the latent image formation process (2), and the development process (3) among the processes described above, and the charged spacer is directly placed on the electrode substrate or color filter. This is a method of fixing to a predetermined position. Alternatively, the spacer may be transferred to another film or the like and then transferred to the electrode substrate or the color filter again.
The spacer used in the liquid crystal display device of the present invention will be described.
[0025]
In the present invention, since it is necessary that the spacers can be dispersedly arranged by an electrophotographic system, a spacer having a property as a toner is used. A preferable spacer in the present invention includes solid fine particles and a binder resin, and has a charge amount of +2 to +50 μC / g or −5 to −50 μC / g. More preferably, it is +5 to +30 μC / g, or −7 to −30 μC / g. When the absolute value of the charge amount is small (+2 to -5 μC / g), the spacers cannot be dispersedly arranged at predetermined positions. On the other hand, when the absolute value of the charge amount is large (negative than −50 μC / g, +50 μC / More positive than / g), electrostatic aggregation occurs between the spacers, and when the spacers are dispersedly arranged, they cannot be adjusted to a desired height or cannot be dispersedly arranged with high accuracy. The method for adjusting the charge amount of the spacer to the above range is not particularly limited, but it is preferable to use a charge controllable binder resin and / or a charge control agent as described later. Here, the measurement of the charge amount is performed based on the blow-off method. As a blow-off charge amount measuring device, TB-200 manufactured by Toshiba Chemical Corporation is commercially available.
[0026]
The average particle diameter of the solid fine particles is preferably 1 to 30 μm, more preferably 1 to 20 μm, and most preferably 1 to 15 μm. If the average particle size is out of the above range, it may not be used as a spacer.
The coefficient of variation (CV) of the particle size of the solid fine particles is preferably 10% or less, more preferably 8% or less, and still more preferably 6% or less. If the variation coefficient of the particle diameter exceeds 10%, it becomes difficult to keep the thickness of the liquid crystal layer uniform and constant, and image unevenness is likely to occur.
[0027]
The shape of the solid fine particles may be any particle shape such as spherical shape, needle shape, plate shape, scale shape, crushed shape, bowl shape, eyebrow shape, confetti shape, etc., and is not particularly limited. Spherical shape is preferable for uniform uniformity. This is because if the particles are spherical, they can have a constant or nearly constant particle size in all or almost all directions.
[0028]
The solid fine particles include various types and are not particularly limited, and examples thereof include organic crosslinked polymer particles, inorganic particles, and organic / inorganic composite particles. Among these, vinyl-based crosslinked polymer particles and organic inorganic composite particles are preferable in terms of preventing damage to the electrode substrate, the alignment film or the color filter, and obtaining uniformity of the gap distance between the two electrode substrates. Body particles are most preferred.
[0029]
The organic crosslinked polymer particles are not particularly limited. For example, divinylbenzene crosslinked resin particles obtained by polymerizing divinylbenzene alone or copolymerizing with other vinyl monomers (JP-A-1-144429). For example).
The inorganic particles are not particularly limited, and examples thereof include spherical fine particles such as glass, silica, and alumina.
[0030]
The organic inorganic composite particles are composite particles composed of an organic portion and an inorganic portion. In this organic-inorganic composite particle, the proportion of the inorganic part is not particularly limited. For example, it is preferably 10 to 90 wt%, more preferably in terms of inorganic oxide, based on the weight of the organic-inorganic composite particle. Is in the range of 25-85 wt%, more preferably 30-80 wt%. Inorganic oxide conversion indicating the proportion of the inorganic part is expressed as a percentage by weight obtained by measuring the weight before and after firing the organic-inorganic composite particles at a high temperature (for example, 1000 ° C.) in an oxidizing atmosphere such as air. It is. When the ratio of the inorganic part of the organic-inorganic composite particles is below the above range in terms of inorganic oxide, the organic-inorganic composite particles may be softened, and the number of sprays on the electrode substrate may increase, and the above range may be exceeded. In some cases, the alignment film is too hard and damage to the alignment film or disconnection of the TFT is likely to occur.
[0031]
Such organic inorganic composite particles are not particularly limited. For example, an organic polymer skeleton and organic silicon in which a silicon atom is directly chemically bonded to at least one carbon atom in the organic polymer skeleton are contained in the molecule. SiO having a polysiloxane skeleton, and constituting the polysiloxane skeleton ₂ An organic-inorganic composite particle etc. whose quantity is 10 wt% or more can be mentioned. As the organic polymer skeleton, a vinyl polymer is preferable because it provides high resilience capable of controlling the gap control. The organic / inorganic composite particles may be colored by containing a dye and / or a pigment.
[0032]
Although it does not specifically limit as a manufacturing method of organic inorganic composite particle, For example, the following manufacturing method including a condensation process, a polymerization process, and a heat treatment process is mentioned.
A condensation process is a process of hydrolyzing and condensing using a radically polymerizable group containing silicon compound.
The radical polymerizable group-containing silicon compound has the following general formula (1):
[0033]
[Chemical 1]

[0034]
(Where R ^a Represents a hydrogen atom or a methyl group; R ^b Represents a divalent organic group having 1 to 20 carbon atoms which may have a substituent; R ^c Represents at least one monovalent group selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, and an acyl group having 2 to 5 carbon atoms)
And the following general formula (2):
[0035]
[Chemical 2]

[0036]
(Where R ^d Represents a hydrogen atom or a methyl group; R ^e Represents at least one monovalent group selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, and an acyl group having 2 to 5 carbon atoms)
And the following general formula (3):
[0037]
[Chemical 3]

[0038]
(Where R ^f Represents a hydrogen atom or a methyl group; R ^g Represents a divalent organic group having 1 to 20 carbon atoms which may have a substituent; R ^h Represents at least one monovalent group selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, and an acyl group having 2 to 5 carbon atoms)
It is preferably a compound represented by at least one general formula selected from the group consisting of or a derivative thereof.
[0039]
The polymerization step is a step of obtaining particles by radical polymerization reaction of radically polymerizable groups during and / or after the condensation step.
The heat treatment step is a step of drying and firing the polymer particles produced in the polymerization step at a temperature of preferably 800 ° C. or lower, more preferably 600 ° C. or lower. The heat treatment step is preferably performed, for example, in an atmosphere having an oxygen concentration of 10% by volume or less or under reduced pressure.
[0040]
A coloring step for coloring the produced particles may be further included during and / or after at least one step selected from the condensation step, the polymerization step and the heat treatment step.
The solid fine particles may be colored by containing at least one selected from the group consisting of dyes and pigments. The color is preferably a light that does not easily transmit light or a color that does not transmit light because the light leakage of the spacer itself can be prevented and the image quality contrast can be improved. Examples of colors that are difficult to transmit or do not transmit light include black, dark blue, amber, purple, blue, dark green, green, brown, red, and the like, and particularly preferably black, dark Blue and scarlet.
[0041]
The dye and / or pigment may be simply contained in the solid fine particles, or may have a structure in which the dye and / or pigment and the matrix constituting the particle body are linked by chemical bonding.
Examples of the binder resin include homopolymers or copolymers of ethylenically unsaturated monomers, polyester resins, and epoxy resins. These binder resins may be used alone or in combination of two or more.
[0042]
The ethylenically unsaturated monomer used as the raw material for the homopolymer or copolymer of the ethylenically unsaturated monomer is not particularly limited, and examples thereof include vinyl ester monomers (such as vinyl acetate) and vinyl. Aromatic monomers (styrene, vinyl toluene, α-methyl styrene, α-chlorostyrene, vinyl naphthalene, vinyl xylene, etc.), (meth) acrylic monomers ((meth) acrylic acid, methyl (meth) acrylate) , Ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, butyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, cyclohexyl (meth) ) Acrylate, etc.), conjugated diolefin monomers (butadiene, And so on) and ethylenically unsaturated carboxylic acids (fumaric acid, maleic anhydride, etc.). Among these, (meth) acrylic acid ester and styrene are preferable because of their high fixability.
[0043]
As the binder resin, a homopolymer or copolymer of an ethylenically unsaturated monomer is preferable from the viewpoint of further improving the fixability, and among these, a (meth) acrylic resin and a (meth) acrylic-styrene resin are preferable. Most preferred is at least one selected from the group consisting of
The glass transition temperature of binder resin becomes like this. Preferably it is 40-100 degreeC, More preferably, it is 45-90 degreeC, More preferably, it is 50-80 degreeC. When the glass transition temperature is less than 40 ° C., the spacer may cause fusion during storage, or the dispersibility when dispersedly arranged on the electrode substrate may deteriorate. On the other hand, when the glass transition temperature exceeds 100 ° C., the binder resin is not easily melted during heating or pressurizing for dispersive arrangement, and therefore, the fixability to the electrode substrate or the color filter may be insufficient.
[0044]
The softening temperature of the binder resin is preferably 50 to 160 ° C, more preferably 60 to 150 ° C, and still more preferably 70 to 140 ° C. If the softening temperature is less than 50 ° C., the spacer may cause fusion or the like during storage, or the dispersibility when dispersed on the electrode substrate may deteriorate. On the other hand, when the softening temperature exceeds 160 ° C., the binder resin is hardly melted during heating or pressurizing when it is dispersedly arranged, and therefore, the fixability to the electrode substrate or the color filter may be insufficient.
[0045]
In general, a binder resin containing an electron donating substituent such as basic nitrogen exhibits positive chargeability, and a binder resin containing an electron accepting substituent such as chlorine or fluorine exhibits negative chargeability. For example, polyester resin has strong negative chargeability, and (meth) acrylic resin and styrene / (meth) acrylic resin have neutral to weak negative chargeability.
In the present invention, binder resins exhibiting charge controllability are preferable, and negative chargeability includes polyester resins, (meth) acrylic resins having an acid group such as (meth) acrylic acid, and styrene / (meth) acrylic. Based resins are preferred. The positive chargeability is preferably a (meth) acrylic resin or styrene / (meth) acrylic resin into which nitrogen such as dimethylaminoethyl methacrylate is introduced.
[0046]
Further, low-molecular weight olefin resins such as low molecular weight polypropylene and low molecular weight polyethylene, and various waxes such as paraffin wax and carnauba wax can be added as an anti-offset agent at a ratio of 2 to 20% by weight of the total binder resin.
The binder resin may be colored by including at least one selected from the group consisting of dyes and pigments. The color is preferably a color that is difficult to transmit light or that does not transmit light in terms of preventing light leakage and improving image quality contrast. Examples of colors that are difficult to transmit or do not transmit light include black, dark blue, amber, purple, blue, dark green, green, brown, red, and the like, and particularly preferably black, dark Blue and scarlet.
[0047]
There are no particular limitations on the dyes and pigments that can be used to color the binder resin.
The weight ratio of the binder resin to the solid fine particles is not particularly limited, but is preferably 1 to 200%, more preferably 3 to 100%, and particularly preferably 5 to 50%. If the weight ratio of the binder resin exceeds 200%, the resin content increases, and the area of spacer dispersion arrangement increases when melted, and spacers are dispersed and arranged in the display area of the liquid crystal display panel. Even if they are dispersed, the display area may be covered and the image quality of the liquid crystal display plate may be degraded. On the other hand, when the weight ratio of the binder resin is small, the fixability is lowered.
[0048]
The binder resin is preferably present on the surface of the solid fine particles, and may cover at least a part of the surface of the solid fine particles, or may be chemically bonded to the surface of the solid fine particles.
The thickness of the binder resin layer in that case is not particularly limited, but is usually in the range of 0.01 to 5 μm, preferably in the range of 0.05 to 2 μm. If the thickness is smaller than the above range, the fixability may be deteriorated. If the thickness is larger than the above range, the area of the spacer is increased and the spacers are dispersed in the display area of the liquid crystal display panel. Even if it is dispersedly arranged in the non-display area, the display area may be covered and the display quality of the liquid crystal display panel may be lowered.
[0049]
The average particle diameter when the binder resin layer is present on the surface of the solid fine particles (the average particle diameter of the solid fine particle body provided with the thickness of the binder resin layer) is not particularly limited, but preferably 1.5 to 25 μm, More preferably, it is 2-25 micrometers, More preferably, it is 2.5-17 micrometers.
The method of coating the solid fine particles with the binder resin or the method of chemically bonding the surface of the solid fine particles and the binder resin is not particularly limited. For example, the solid fine particles are dispersed in a binder resin solution and mixed sufficiently. After that, the solvent is removed by evaporation and the resulting mass is pulverized, or the solid fine particles are dispersed in the melted binder resin, kneaded and sufficiently dispersed, and the mass is pulverized after cooling. Introducing various functional groups (vinyl group, epoxy group, hydroxyl group, etc.) onto the surface of the solid fine particles, polymerizing the monomer starting from the functional group, or reacting the functional group with the polymer to graft onto the particle surface There are methods.
[0050]
In addition to the methods described above, “surface modification” (Chemical Review No. 44 edited by The Chemical Society of Japan, pages 45-52, published in 1987) and “surface modification of powder and highly functional technology” (“ In-situ polymerization method, coacervation method, interfacial polymerization method, submerged curing coating method, liquid described in detail in “Surface”, Vol. 25, No. 1, pages 1-19 and cover photo, published in 1987) The coating can also be performed by a conventionally known resin coating method such as a medium drying method, a high-speed air current impact method, an air suspension coating method, or a spray drying method. In particular, the impact method in high-speed air current is, for example, mixing solid fine particles and binder resin powder, dispersing the mixture in the gas phase, and applying mechanical thermal energy mainly composed of impact force to the particles. By giving to the binder resin powder, it is a method of coating the surface of the particles with the binder resin, and it is most preferable because it can be easily coated. The average particle size of the binder resin powder used when performing this high-speed air-flow impact method is not particularly limited, but is preferably 2 μm or less, more preferably 1.8 μm or less, and most preferably 1 μm or less. is there.
[0051]
There are no particular limitations on the apparatus using the high-speed air-flow impact method, but examples include a hybridization system manufactured by Nara Machinery Co., Ltd., a mechano-fusion system manufactured by Hosokawa Micron Co., Ltd., and a kryptron manufactured by Kawasaki Heavy Industries, Ltd. There are systems.
As described above, the spacer of the present invention can further contain a charge control agent. The charge control agent is not particularly limited and may be organic or inorganic. Those that exhibit positive charge are electron donating substances. For example, organic substances are basic dyes such as nigrosine dyes, quaternary ammonium compounds, fatty acid metal salts, benzoguanamine resins, etc., and inorganic substances are amino groups. Surface treated (hydrophobic) silica, (hydrophobic) titania and the like. Those that exhibit negative chargeability are electron-accepting substances, such as azo metal-containing dyes, metal complexes of salicylic acid derivatives, chlorinated paraffins, chlorinated polyesters, etc. for organic substances, and (hydrophobic) silica for inorganic substances, etc. There is.
[0052]
The amount of the charge control agent is not particularly limited, but is preferably 0.01 to 20% by weight, more preferably 0.5 to 15% by weight, and still more preferably 1 to 10% by weight with respect to the binder resin. If the amount of the charge control agent is too large or too small, the charge amount of the spacer does not fall within the above range.
Furthermore, the spacer of the present invention may contain ferrite-based magnetic materials, external additives such as silica, antioxidants, release agents, and the like as necessary, in addition to the above-described additives.
[0053]
In the liquid crystal display device of the present invention, other than the spacers, electrode substrates, sealing materials, liquid crystal materials, and the like can be used in the same manner as in the past.
The electrode substrate has a substrate such as a glass substrate or a film substrate, and an electrode formed on the surface of the substrate, and an alignment film formed so as to cover the electrode on the surface of the electrode substrate as necessary. Also have. A color-compatible liquid crystal display device has a color filter. An epoxy resin adhesive sealing material or the like is used as the sealing material. As the liquid crystal, those conventionally used may be used. For example, biphenyl, phenylcyclohexane, Schiff base, azo, azoxy, benzoate, terphenyl, cyclohexylcarboxylate, biphenylcyclohexane , Pyrimidine-based, dioxane-based, cyclohexylcyclohexane ester-based, cyclohexylethane-based, cyclohexene-based, and fluorine-based liquid crystals can be used.
[0054]
As a method for manufacturing the liquid crystal display device of the present invention, for example, an in-plane spacer is dispersed on a predetermined position by electrophotography on one of the two electrode substrates, an epoxy resin or the like. A material obtained by dispersing sealant spacers on the other electrode substrate and applying it to the adhesive seal part of the other electrode substrate by means of screen printing or the like is applied, an appropriate pressure is applied, and 1 at a temperature of 100 to 180 ° C. Heating for up to 60 minutes or irradiation amount of 40-300 mJ / cm ² Although the adhesive sealing material is heated and cured by UV irradiation, a method of injecting liquid crystal and sealing the injection portion can be mentioned, but it is not limited thereto.
[0055]
The liquid crystal display device of the present invention has the same application as a conventional liquid crystal display device, for example, as an image display element for a television, a monitor, a personal computer, a word processor, a car navigation system, a DVD, a digital video camera, a PHS (personal digital assistant), etc. used.
[0056]
【Example】
The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto.
Unless otherwise specified, “parts” and “%” in the examples represent “parts by weight” and “% by weight”, respectively.
<Average particle size of solid fine particles, coefficient of variation of particle size>
The solid fine particles were observed with an electron microscope, the particle diameters of 200 arbitrary particles in the photographed image were measured, and the average particle diameter, the standard deviation of the particle diameter, and the coefficient of variation of the particle diameter were determined according to the following formulas.
[0057]
[Expression 1]

[0058]
[Expression 2]

[0059]
[Equation 3]

[0060]
<Glass transition temperature of binder resin>
It measured using DSC-7 made from Perkin Elmer.
<Softening temperature of binder resin>
Using a flow tester CFT-500C manufactured by Shimadzu Corporation, the temperature was measured by the temperature rising method under the following conditions, and the outflow start temperature was defined as the softening temperature.
[0061]
Starting temperature: room temperature
End temperature: 230 ° C
Temperature increase rate: 6 ° C / min
Test load: 20.0kgf
Die hole diameter: 0.50mm
Die length: 1.00mm
<Average particle size of binder resin>
The measurement was performed in accordance with the method for measuring the average particle size of the solid fine particles.
<Charge of spacer>
Based on the blow-off method, iron powder (DSP-128 manufactured by Dowa Iron Powder Co., Ltd.) and spacers were allowed to stand at 25 ° C. and 60% RH for 24 hours, and then 28.50 g of iron powder and 1.50 g of spacers were 1 in a bottle. After mixing for a minute, it was measured with a blow-off charge measuring device (TB-200 manufactured by Toshiba Chemical Corporation).
<Example of synthesis of solid fine particles>
In a four-necked flask equipped with a condenser, thermometer, and dripping port, a solution (solution A) in which 4.5 g of 25% aqueous ammonia solution and 387.3 g of water were mixed was placed, and the temperature was maintained at 25 ± 2 ° C. and stirred. In this solution, 62 g of γ-methacryloxypropyltrimethoxysilane, 28 g of vinyltrimethoxysilane, 5 g of tetraethoxysilane tetramer, and 2,2′-azobis- (4-methoxy-) as a radical polymerization initiator. 2,4-dimethylvaleronitrile) (solution B) mixed with 0.34 g was added from the dropping port, and γ-methacryloxypropyltrimethoxysilane, vinyltrimethoxysilane, and tetraethoxysilane 4-5. Co-hydrolysis and polycondensation with the monomer were performed. After 20 minutes with continued stirring, N ₂ Radical polymerization was carried out by heating to 60 ± 5 ° C. in an atmosphere.
[0062]
After heating for 2 hours, the mixture was cooled to room temperature to obtain a suspension of polymer particles. This suspension was subjected to solid-liquid separation by filtration, and the obtained cake was washed three times by decantation with methanol.
The washed cake was filtered, and the resulting particles were calcined at 300 ° C. for 2 hours in a nitrogen atmosphere to obtain spherical solid fine particles (1).
[0063]
The obtained solid fine particles (1) are an organic-inorganic composite, the average particle size is 5.7 μm, the particle size variation coefficient is 3.5%, and the proportion of the polysiloxane skeleton is based on the weight of the solid fine particles (1). SiO ₂ The amount converted was 46.0 wt%.
<Example of binder resin synthesis>
A resin having a monomer composition shown in Table 2 as a binder was synthesized by soap-free polymerization. Table 2 also shows the glass transition temperature, softening temperature, and average particle size.
[0064]
[Table 2]

[0065]
[Example 1]
As solid fine particles, 35 g of solid fine particles (1) obtained in the synthesis example, 14 g of binder (1), and an azo dye metal complex represented by the following chemical formula as a charge control agent for negative charge (where M = Cr, R1 = After mixing 0.2 g of R3 = Cl, R2 = R4 = H) and 0.5 g of low molecular weight polypropylene, a high-speed impact in air current method was performed using a hybridization system NHS-0 manufactured by Nara Machinery Co., Ltd. The surface of the solid fine particles (1) was coated with the binder (1) to obtain adhesive particles (1). The binder of the adhesive particles (1) contained a charge control agent and a low molecular weight polypropylene.
[0066]
[Formula 4]

[0067]
Next, 0.07 g of hydrophobic silica ultrafine particles (Aerosil R972 manufactured by Nippon Aerosil Co., Ltd., average particle diameter 16 nm) as an external additive was stirred for 10 seconds in a coffee mill, and then the adhesive particles (1 35 g was added and stirred and mixed for 20 seconds, and an external additive was adhered to the surface of the adhesive particles (1) to obtain a spacer (1).
The obtained spacer (1) had an average particle size of 6.3 μm and a charge amount of −26 μC / g.
[Example 2]
Example 1 is the same as Example 1 except that the charge controllable binder (2) exhibiting negative chargeability is used instead of the binder (1), and no charge control agent comprising an azo dye metal complex is used. Thus, a spacer (2) was obtained.
[0068]
The obtained spacer (2) had an average particle diameter of 6.2 μm and a charge amount of −18 μC / g.
[Example 3]
In Example 1, 0.2 g of nigrosine, which is a positively chargeable charge control agent, was used as the charge control agent instead of the azo dye metal complex, and without using an external additive composed of ultrafine hydrophobic silica particles, the others were In the same manner as in Example 1, a spacer (3) was obtained.
[0069]
The obtained spacer (3) had an average particle diameter of 6.4 μm and a charge amount of +15 μC / g.
[Comparative Example 1]
In Example 1, a comparative spacer (1) was obtained in the same manner as in Example 1 except that no charge control agent was used.
[0070]
The obtained comparative spacer (1) had an average particle diameter of 6.4 μm and a charge amount of −2 μC / g.
[Comparative Example 2]
In Example 1, a comparative spacer (2) was obtained in the same manner as in Example 1 except that the amount of the charge control agent comprising an azo dye metal complex was changed to 3.0 g.
[0071]
The obtained comparative spacer (2) had an average particle diameter of 6.1 μm and a charge amount of −74 μC / g.
[Comparative Example 3]
In Example 3, a comparative spacer (3) was obtained in the same manner as in Example 3 except that the amount of the charge control agent comprising nigrosine was changed to 3.0 g.
[0072]
The obtained comparative spacer (3) had an average particle size of 6.5 μm and a charge amount of +67 μC / g.
[Example 4]
In the TFT type liquid crystal display device, in order to disperse and arrange the spacers at intervals of 70 μm on the black matrix of the color filter of the electrode substrate on which the color filters are disposed, a pattern in which the spacers are to be dispersed and arranged is first prepared.
[0073]
Next, using an electrophotographic method comprising the Carlson method as shown in FIG. 2, the spacers were fixed on the black matrix on the color filter, and the spacers were dispersedly arranged on the black matrix of the color filter. That is, the pattern is first formed as an electrostatic latent image on the photosensitive member, and then the spacer (1) obtained in Example 1 is attached to the electrostatic latent image, to the electrode substrate on which the color filter is installed. After the transfer, the image was fixed by heating at 150 ° C. The spacers are dispersed and arranged at predetermined positions on the black matrix every 70 μm, and the density of the dispersed arrangement is 204 pieces / mm. ² Met.
[0074]
Next, a TFT-type liquid crystal display device was produced according to the following procedure. The transparent electrode substrate having the TFT element and the transparent electrode substrate having the color filter in which the spacers are dispersed and arranged as described above are bonded together with an adhesive sealant, and then the gap between the two electrode substrates is reduced to a further atmospheric pressure. By returning, a fluorine-based TN liquid crystal for TFT was injected, and the injection portion was sealed. And the polarizing film was stuck on the outer side of the upper and lower electrode substrates, and the TFT type liquid crystal display device (1) was obtained.
[0075]
The obtained liquid crystal display device (1) had no color unevenness. From this, it can be seen that the liquid crystal display device (1) has excellent gap uniformity, and the spacers are dispersed and arranged with high accuracy, and there is no variation in height. Further, the liquid crystal display device (1) had a high contrast and was not rough. From this, it can be seen that the spacer does not exist in the display area. As described above, the liquid crystal display device (1) exhibited good display quality. These results are shown in Tables 3 and 4.
[Examples 5 and 6]
Example 4 is the same as Example 4 except that instead of the spacer (1), the spacers (2) and (3) obtained in Examples 2 and 3 were used as spacers to be attached to the electrostatic latent image. Thus, TFT type liquid crystal display devices (2) and (3) were obtained. The results are shown in Tables 3 and 4.
[Example 7]
In Example 4, a TFT liquid crystal display device (4) was obtained in the same manner as in Example 4 except that the spacer dispersion method was changed from the Carlson method to the toner jet method. The results are shown in Tables 3 and 4.
[Comparative Examples 4 to 6]
Example 4 is the same as Example 4 except that the comparative spacers (1) to (3) obtained in Comparative Examples 1 to 3 were used instead of the spacer (1) as the spacer to be attached to the electrostatic latent image. Similarly, comparative TFT type liquid crystal display devices (1) to (3) were obtained. The results are shown in Tables 3 and 4.
[Comparative Example 7]
In Example 4, a comparative TFT type liquid crystal display device (4) was prepared in the same manner as in Example 4 except that the spacer arrangement method was changed from the electrophotographic method to the conventionally used high-speed airflow type dry spraying method. ) For dispersion of spacers, DISPA-μR made by Nisshin Engineering Co., Ltd. is used, and the number of dispersion is about 200 ± 20 / mm. ² It was. The results are shown in Tables 3 and 4.
[0076]
[Table 3]

[0077]
[Table 4]

[0078]
【The invention's effect】
According to the present invention, accurate dispersion and arrangement of spacers in a non-display area and adjustment to a desired height can be easily and easily performed. As a result, there is no reduction in contrast, roughness, color unevenness, etc., and display quality is improved. A very excellent liquid crystal display device can be obtained.
[Brief description of the drawings]
FIG. 1 is a schematic sectional view showing an example of a liquid crystal display device of the present invention.
FIG. 2 is a diagram illustrating a basic configuration of an electrophotographic system.
FIG. 3 is a diagram showing a normal development method and a reversal development method.
[Explanation of symbols]
2 Sealing material
3 Seal part spacer
4 Alignment film
5 electrodes
6 Polarizing film
7 Liquid crystal
8 In-plane spacer
11 Lower glass substrate
12 Upper glass substrate
21 Photosensitive drum
22 Charger
23 Exposure unit
24 Developer
25 Transfer device
26 Fixing device
27 Static eliminator
28 Cleaner
29 Recording paper
110 Lower electrode substrate
120 Upper electrode substrate

Claims (10)

A liquid crystal display device comprising: a pair of electrode substrates disposed opposite to each other with a liquid crystal material interposed therebetween; and a spacer that is selectively distributed between the electrode substrates to maintain a space between the electrode substrates. the all SANYO which are distributed in a predetermined position by using an electrophotographic system,
The spacer includes solid fine particles and a resin layer made of a binder resin formed on the surface of the solid fine particles, and the charge amount is −5 to −50 μC / g,
A binder resin in which the resin layer is a negatively chargeable resin selected from a polyester resin, a (meth) acrylic resin having an acid group introduced therein, and a styrene / (meth) acrylic resin, and / or an azo metal-containing dye And a liquid crystal display device comprising at least one charge control agent selected from the group consisting of a metal complex of a salicylic acid derivative, chlorinated paraffin, chlorinated polyester, and negatively charged hydrophobic silica . A liquid crystal display device comprising: a pair of electrode substrates disposed opposite to each other with a liquid crystal material interposed therebetween; and a spacer that is selectively distributed between the electrode substrates to maintain a space between the electrode substrates. the all SANYO which are distributed in a predetermined position by using an electrophotographic system,
The spacer includes solid fine particles and a resin layer made of a binder resin formed on the surface of the solid fine particles, and the charge amount is +2 to +50 μC / g,
The resin layer is a binder resin that is a positively chargeable resin selected from nitrogen-introduced (meth) acrylic resin and styrene / (meth) acrylic resin, and / or basic dye, quaternary ammonium compound , A liquid crystal display device comprising at least one charge control agent selected from the group consisting of fatty acid metal salts, benzoguanamine resins, hydrophobic silica surface-treated with amino groups, and hydrophobic titania . The electrophotographic method is Carlson method or toner jet method, a liquid crystal display device according to claim 1 or 2 wherein. The liquid crystal display device according to claim 1, wherein the predetermined position is a non-display area. The liquid crystal display device according to claim 1, wherein the solid fine particles are organic-inorganic composite fine particles. In a method of manufacturing a liquid crystal display device, comprising: a pair of electrode substrates disposed opposite to each other with a liquid crystal material interposed therebetween; and a spacer that is selectively distributed between the electrode substrates and maintains a distance between the electrode substrates. Including dispersing the spacers at predetermined positions using electrophotography ,
The spacer includes solid fine particles and a resin layer made of a binder resin formed on the surface of the solid fine particles, and the charge amount is −5 to −50 μC / g,
A binder resin in which the resin layer is a negatively chargeable resin selected from a polyester resin, a (meth) acrylic resin having an acid group introduced therein, and a styrene / (meth) acrylic resin, and / or an azo metal-containing dye And a method for producing a liquid crystal display device comprising at least one charge control agent selected from the group consisting of a metal complex of a salicylic acid derivative, chlorinated paraffin, chlorinated polyester and negatively charged hydrophobic silica . In a method of manufacturing a liquid crystal display device, comprising: a pair of electrode substrates disposed opposite to each other with a liquid crystal material interposed therebetween; and a spacer that is selectively distributed between the electrode substrates and maintains a distance between the electrode substrates. Including dispersing the spacers at predetermined positions using electrophotography ,
The spacer includes solid fine particles and a resin layer made of a binder resin formed on the surface of the solid fine particles, and the charge amount is +2 to +50 μC / g,
The resin layer is a binder resin that is a positively chargeable resin selected from nitrogen-introduced (meth) acrylic resin and styrene / (meth) acrylic resin, and / or basic dye, quaternary ammonium compound , A fatty acid metal salt, a benzoguanamine-based resin, a hydrophobic silica surface-treated with an amino group, and at least one charge control agent selected from the group consisting of hydrophobic titania . A method of dispersing and arranging spacers on a substrate, wherein the spacers according to any one of claims 1 to 5 are dispersed and arranged at predetermined positions using an electrophotographic system. . A spacer for a liquid crystal display panel for dispersive arrangement using an electrophotographic method,
A solid fine particle and a resin layer made of a binder resin formed on the surface of the solid fine particle, and the charge amount is −5 to −50 μC / g,
A binder resin in which the resin layer is a negatively chargeable resin selected from a polyester resin, a (meth) acrylic resin having an acid group introduced therein, and a styrene / (meth) acrylic resin, and / or an azo metal-containing dye A spacer for a liquid crystal display panel , comprising at least one charge control agent selected from the group consisting of a metal complex of a salicylic acid derivative, chlorinated paraffin, chlorinated polyester, and negatively charged hydrophobic silica . A spacer for a liquid crystal display panel for dispersive arrangement using an electrophotographic method,
A solid fine particle and a resin layer made of a binder resin formed on the surface of the solid fine particle, the charge amount is +2 to +50 μC / g,
The resin layer is a binder resin that is a positively chargeable resin selected from nitrogen-introduced (meth) acrylic resin and styrene / (meth) acrylic resin, and / or basic dye, quaternary ammonium compound , A spacer for a liquid crystal display panel , comprising at least one charge control agent selected from the group consisting of a fatty acid metal salt, a benzoguanamine resin, a hydrophobic silica surface-treated with an amino group, and a hydrophobic titania .

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