JP4108164B2

JP4108164B2 - Production method of chemisorbed monolayer

Info

Publication number: JP4108164B2
Application number: JP31723097A
Authority: JP
Inventors: 小川　　一文; 忠大竹; 幸生野村
Original assignee: Panasonic Corp; Matsushita Electric Industrial Co Ltd
Current assignee: Panasonic Corp; Panasonic Holdings Corp
Priority date: 1997-11-18
Filing date: 1997-11-18
Publication date: 2008-06-25
Anticipated expiration: 2017-11-18
Also published as: JPH11147074A

Description

【０００１】
【発明の属する技術分野】
本発明は、化学吸着単分子膜の製造方法に関する。さらに詳しくは、フッ素系防汚性単分子膜、液晶用配向膜、偏光膜、位相差膜、分子素子用導電膜など、分子レベルで用いる薄膜材料である化学吸着単分子膜の製造方法に関する。
【０００２】
【従来の技術】
従来、化学吸着単分子膜の製造方法としては、化学吸着液に基材を浸漬し、前記化学吸着液中で基材表面と化学吸着液の接触界面において、すなわち溶媒中の化学吸着物質と基材表面間において所定の時間化学反応させる方法が一般的に用いられてきた。
【０００３】
例えば、あらかじめ直鎖状炭化水素基及びＳｉを含むシラン系界面活性剤（以下、化学吸着物質あるいは化学吸着化合物ともいう）を用い、１重量％程度の濃度で非水系の溶媒に溶かして化学吸着溶液を調整しておき、この化学吸着液に基材を浸漬し、前記化学吸着液中で所定の時間化学吸着反応させた後化学吸着液から基材を取り出し、表面に付着した余分の化学吸着液を非水系の有機溶媒で洗浄除去する方法が用いられたきた。
【０００４】
【発明が解決しようとする課題】
しかしながら、従来の化学吸着単分子膜の作成方法では、１重量％程度の濃度で室温で行う場合、反応が飽和するまでおよそ２時間程度を必要とし極めて効率が悪かった。そこで、この反応時間を短縮する方法として、化学吸着液の濃度を上げる方法、あるいは化学吸着中の温度を上げる方法が試みられてきた。ところが、加熱する方法では、せいぜい５０〜６０℃程度が限界であり、この程度の加熱では高々１０〜２０％程度しか反応時間を短縮できなかった。また、それ以上加熱して化学吸着を行うと、吸着反応中溶媒が蒸発してしまったり、化学吸着された単分子膜の配向が悪くなるなどの問題があった。一方、濃度を上げる方法では、高価な化学吸着物質を無駄にすることになり効率が悪かった。また、作成された化学吸着液の安定性の面でも不都合であった。
【０００５】
本発明は、前記従来の問題を解決するため、厚みはナノメータレベルできわめて薄く、均一な化学吸着単分子膜を短時間、高能率に製造できる方法を提供することを目的とする。
【０００６】
【課題を解決するための手段】
前記目的を達成する本発明に係る化学吸着単分子膜の製造方法は、
沸点が１００〜２５０℃のシリコーン系非水系の有機溶媒と、ＳｉＣｌ ₃ 基を有するシラン系界面活性剤とを含有する化学吸着液を、表面にＯＨ基を有する基板に乾燥雰囲気中で塗布する工程、
前記有機溶媒を乾燥雰囲気中で蒸発させて濃縮させつつ、前記吸着液中のシラン系界面活性剤が有するＣｌと前記基板表面のＯＨ基とを化学反応させて前記シラン系界面活性剤分子を前記基板表面に一端で結合固定する工程、
その後、有機溶媒を用い、前記基板表面に残った未反応のシラン系界面活性剤を乾燥雰囲気中で洗浄除去する工程、および
前記基板表面を水分にさらす工程、
を有する。
【０００７】
洗浄除去する工程と、前記基板表面を水分にさらす工程との間に、さらに所望の方向に前記基板を立てて洗浄液を液切りし、液切り方向に前記固定された前記シラン系界面活性剤分子を配向させる工程を含んでも良い。
【０００８】
また、乾燥雰囲気として相対湿度３０％以下の雰囲気を用いると、白濁がないより完璧な化学吸着単分子膜を製造する上で都合がよい。
【０００９】
さらにまた、炭素鎖またはシロキサン結合鎖の末端または一部が、３フッ化炭素基（−ＣＦ₃）、メチル基（−ＣＨ₃）、ビニル基（−ＣＨ＝ＣＨ₂）、アリル基（−ＣＨ＝ＣＨ−）、アセチレン基（炭素−炭素の３重結合）、フェニル基（−Ｃ₆Ｈ₅）、アリール基（−Ｃ₆Ｈ₄−）、ハロゲン原子、アルコキシ基（−ＯＲ；Ｒはアルキル基を表す）、シアノ基（−ＣＮ）、カルボニル基（＝ＣＯ）、及びカルボキシ基（−ＣＯＯ−）から選ばれる少なくとも一つの有機基で置換されていると、いろいろな表面エネルギーをもつ化学吸着単分子膜を作成できて好都合である。
【００１０】
さらにまた、界面活性剤として複数種のシラン系界面活性剤を混合して用いると、表面が分子レベルで凸凹な単分子膜を製造でき、新たな機能を発現する上で都合がよい。
【００１１】
一方、化学吸着物質に感光性基を組み込み、吸着・洗浄後、または液切り予備配向後、さらに偏光板を介して露光する工程を行うと、化学吸着された分子は偏光方向に沿って配向され且つ重合されるので、分子が配向固定された化学吸着単分子膜を製造方法する上で都合がよい。
【００１４】
また、化学吸着液を塗布する工程において、オフセット印刷、スクリーン印刷、またはロールコート法を用いると、必要以上に化学吸着液を使用しないのでより効率よく被膜を形成できる。
【００１５】
また、化学吸着液を塗布する工程において、オフセット印刷、スクリーン印刷、またはロールコート法を行う際、化学吸着液の粘度を１〜５００００ｃＳｔに制御しておくと、塗布後の溶媒蒸発時間を短くでき、且つ液垂れを防ぐことができて都合がよい。さらにまた、化学吸着液の粘度制御にシリコーンを用いると、分子量の調節のみで粘度を制御できて都合がよい。
【００１８】
【実施例】
以下実施例を用いて本発明をさらに具体的に説明する。
（実施例１）
表面に透明電極の形成されたガラス基板１（表面に水酸基を多数含む）を準備し、あらかじめよく洗浄脱脂した。一方、末端に被膜の表面エネルギーを小さくする官能基（−ＣＦ₃等）を一つ組み込んだ直鎖状炭化水素基及びＳｉを含むシラン系界面活性剤（以下、化学吸着物質あるいは化学吸着化合物ともいう）、ＣＦ₃（ＣＦ₂）₇（ＣＨ₂）₂ＳｉＣｌ₃を用い、１重量％の濃度で非水系の溶媒に溶かして化学吸着溶液を調製しておいた。このとき、非水系溶媒（水を含まない溶媒）としては、良く脱水したヘキサメチルシリコーン（ｂｐ．１００℃、これ以外に、沸点が２５０℃程度までの非水系有機溶媒なら、多少蒸発時間が長くはなるが実用上、何ら問題なく使用可能であった。）を用いた。このようにして調製された溶液を吸着溶液２とし、乾燥雰囲気中（相対湿度３０％以下）で、この吸着溶液２の中に前記基板１を１分間程度浸漬（コーター等で塗布しても良い）した（図１）。その後、液から引き上げて、同雰囲気中でシリコーン溶媒を蒸発させ、基板表面の化学吸着物質濃度が１００％になるまで濃縮し、その後さらに１０分間反応させた。すなわち、前記化学吸着物質のみからなる被膜を前記基板表面に５μｍ膜厚程度に形成し化学吸着剤と基板表面の反応を加速させた。その後、さらに同様の乾燥雰囲気中で良く脱水した水を含まない非水系の溶媒であるクロロホルム３を用いて洗浄した後洗浄液より引き上げて液切りし、次いで水分を含む空気中に暴露した（図２）。５は洗浄液からの引き上げ方向を示す。
【００１９】
以上の処理により、前記クロロシラン系界面活性剤が反応してなる化学吸着単分子膜４が基板表面の水酸基が含まれていた部分にシロキサンの共有結合を介して化学結合した状態で約１ｎｍの膜厚で形成された。なお、このとき化学吸着膜の臨界表面エネルギーは、ジスマンプロットを用いて測定すると約１０ｍＮ／ｍであった。また、水に対する接触角度は１２０度程度有り、防汚性に優れた化学吸着単分子膜が得られた。
【００２０】
ちなみに、基板表面と界面活性剤との反応においては、はじめに下記式（化１）の結合が生成され、さらに、溶媒洗浄後一般空気中に取り出すと、空気中の水分と反応して式（化２）の結合が生成されたものと考えられた。なお、このとき吸着された分子の炭素鎖はＦＴＩＲで分析すると液切り方向（洗浄液からの引き上げ方向５と反対の方向）にある程度傾斜して配向していた（図３）。
【００２１】
【化１】

【００２２】
【化２】

【００２３】
さらにまた、対剥離強度も碁盤目試験で確認したが全く剥離しなかった。
前記の一連の化学吸着単分子膜形成工程において、溶媒蒸発後には前記クロロシラン系界面活性剤が１００％に濃縮された状態で基板表面に塗布されたことになり、その状態でクロロシラン系界面活性剤のＳｉＣｌ基と前記基板表面の水酸基とで脱塩酸反応が生じるので、通常１〜２時間必要とする吸着時間が、１１分間と極めて短時間に短縮できた。
【００２４】
（実施例２）
表面に透明電極の形成されたガラス基板（表面に水酸基を多数含む）を準備し、あらかじめよく洗浄脱脂した。一方、末端に被膜の表面エネルギーを制御する官能基を一つ組み込んだ直鎖状炭化水素基及びＳｉを含むシラン系界面活性剤（以下、化学吸着物質あるいは化学吸着化合物ともいう）、ＣＨ₃（ＣＨ₂）₁₄ＳｉＣｌ₃と感光基を組み込んだシラン系界面活性剤、Ｃ₆Ｈ₅ＣＨ＝ＣＨＣＯＣ₆Ｈ₄Ｏ（ＣＨ₂）₆ＳｉＣｌ₃（モル比で１：１に混合して用いた）を用い、１重量％の濃度で非水系の溶媒に溶かして化学吸着溶液を調整しておいた。このとき、非水系溶媒（水を含まない溶媒）としては、良く脱水したオクタメチルシリコーン（ｂｐ．１００℃、これ以外に、沸点が２５０℃程度までの非水系有機溶媒なら、多少蒸発時間が長くはなるが実用上、何ら問題なく使用可能であった。）を用いた。このようにして調製された溶液を吸着溶液とし、乾燥雰囲気中（相対湿度３０％以下）で、この吸着溶液２の中に前記基板を１分間程度浸漬（塗布しても良い）した。
【００２５】
その後、液から引き上げて、同雰囲気中でシリコーン溶媒を蒸発させ、基板表面の化学吸着物質濃度が１００％になるまで濃縮し、その後さらに５分間反応させた。すなわち、前記化学吸着物質のみからなる被膜を前記基板表面に形成し化学吸着剤と基板表面の反応を加速させた。その後、さらに同様の乾燥雰囲気中で良く脱水した水を含まない非水系の溶媒であるｎ−ヘキサンを用いて洗浄した後、基板を所望の方向に立てた状態で洗浄液より引き上げて液切りした後、水分を含む空気中に暴露した。
【００２６】
以上の処理により、前記混合クロロシラン系界面活性剤が反応してなる化学吸着単分子膜４’が基板表面の水酸基が含まれていた部分にシロキサンの共有結合を介して化学結合した状態で結合され、結合された分子が引き上げ方向５と反対方向、すなわち液切り方向に沿って配向して約１．７ｎｍの膜厚で形成された。なお、このとき化学吸着膜の臨界表面エネルギーは約２８ｍＮ／ｍであった。
【００２７】
そこで、この状態の基板２枚を用い、化学吸着膜が向かい合うように組み合わせて、配向方向がアンチパラレルになるようにセットし２０ミクロンギヤップの液晶セルを組み立て、ネマチック液晶（ＺＬＩ４７９２；メルク社製）を注入して配向状態を確認すると、注入した液晶分子が洗浄液の液切り方向に向かって、基板に対して約プレチルト角４゜で配向していた。ちなみに、基板表面と界面活性剤との反応においては、はじめに下記式（化３および４）の結合がほぼ１：１の比で生成され、さらに、溶媒洗浄後一般空気中に取り出すと、空気中の水分と反応して式（化５及び６）の結合が生成されたものと考えられた。なお、このとき吸着された分子の炭素鎖はＦＴＩＲで分析すると液切り方向にある程度傾斜して配向していた（図４）。
【００２８】
【化３】

【００２９】
【化４】

【００３０】
【化５】

【００３１】
【化６】

【００３２】
前記の一連の化学吸着単分子膜形成工程において、溶媒蒸発後には前記クロロシラン系界面活性剤が１００％に濃縮された状態で基板表面に塗布されたことになり、その状態でクロロシラン系界面活性剤のＳｉＣｌ基と前記基板表面の水酸基とで脱塩酸反応が生じるので、通常１〜２時間必要とする吸着時間が、６分間と極めて短時間に短縮できた。
【００３３】
次に、この状態の基板を２個用意し、さらにそれぞれの引き上げ方向と直行する方向から３度ずらせて、即ち引き上げ方向と８７度で交差する方向に偏光方向１３が向くように偏光板６（ＨＮＰ´Ｂ：ポラロイド社製）を基板に重ねてセットし、５００Ｗの超高圧水銀灯の３６５ｎｍ（ｉ線）の光７（偏光膜透過後３．６ｍＷ／ｃｍ²）を用いて４００ｍＪ照射した（図５）。照射後の偏光板６を除いた化学吸着単分子膜を図６に示す。図６中、８は膜分子の再配向方向を示す。
以上の処理により、ＦＴＩＲ分析によると化学吸着単分子膜内の化５で示される分子は変化しないが、化６示される感光性基（Ｃ₆Ｈ₅ＣＨ＝ＣＨＣＯＣ₆Ｈ₄−）は、３６５ｎｍ（ｉ線）の光に感光性を示すので、光重合して化７に示したような構造となった。図５〜６中、９は透明電極を表わす。また膜分子の構造を図７に示す。図７中、４”は再配向された感光性基が重合された化学吸着単分子膜を示す。
【００３４】
【化７】

【００３５】
さらに、この状態の基板２枚を用い、図７の化学吸着膜４”が向かい合うように組み合わせて、配向方向がアンチパラレルになるようにセットし２０ミクロンギヤップの液晶セルを組み立て、ネマチック液晶（ＺＬＩ４７９２；メルク社製）を注入して配向状態を確認すると、注入した液晶分子が偏光方向に沿って、基板に対して約プレチルト角４゜で配向していた。
【００３６】
ちなみに、前記化学吸着単分子膜４’中の直鎖状炭素鎖の配向方向をＦＴＩＲを用いて分析すると臨界表面エネルギーとチルト角は変わらなかったが配向方向８は偏光方向１３とほぼ平行方向に変化し、しかも配向ばらつきも、引き上げによる液切り予備配向時より改善されていた。
【００３７】
なお、このとき照射部の吸着分子の配向方向を一方向に揃えるためには、液切り方向と完全に９０゜で交差するのではなく、多少、好ましくは数度以上ずらせる必要がある。もし万一、完全に９０゜に交差させれば、個々の分子が２方向に向いてしまう場合がある。なお、洗浄液液切り方向と平行になるように偏光方向１３を合わせると、さらに配向規制力の優れた単分子膜が得られた。
【００３８】
また、基板表面で選択的に配向方向を変えたい場合には、あらかじめ引き上げ液切りを行った後、偏光板にパターン状のマスクを重ねて２００〜５００ｍＪのエネルギーで３６５ｎｍの波長の紫外線を照射すると、照射された部分のみ配向方向が変化し同一面内の配向膜内でパターン状に配向方向の異なる部分、すなわち、引き上げ液切り方向５と偏光方向１３にそれぞれ沿って液晶が配向する部分を複数箇所設けることができた。
【００３９】
なお、乾燥雰囲気として相対湿度３５％以上の雰囲気を用いた場合には、洗浄しても基板表面に白く被膜が残り簡単には除去できなかった。
また、界面活性剤として直鎖状炭素鎖またはシロキサン結合鎖とクロロシリル基を含むシラン系の界面活性剤を用いたが、アルコキシシラン基またはイソシアネートシラン基を含む界面活性剤も反応速度はやや遅くなるが、利用できた。
【００４０】
さらにまた、界面活性剤として臨界表面エネルギーの異なる複数種のシリコン系界面活性剤、例えば炭素鎖またはシロキサン結合鎖の末端または一部が、３フッ化炭素基（−ＣＦ₃）、メチル基（−ＣＨ₃）、ビニル基（−ＣＨ＝ＣＨ₂）、アリル基（−ＣＨ＝ＣＨ−）、アセチレン基（炭素−炭素の３重結合）、フェニル基（−Ｃ₆Ｈ₅）、アリール基（−Ｃ₆Ｈ₄−）、ハロゲン原子、アルコキシ基（−ＯＲ；Ｒはアルキル基を表し、炭素数１〜３の範囲が好ましい。）、シアノ基（−ＣＮ）、アミノ基（−ＮＨ₂）、水酸基（−ＯＨ）、カルボニル基（＝ＣＯ）、カルボキシ基（−ＣＯＯ−）及びカルボキシル基（−ＣＯＯＨ）から選ばれる少なくとも一つの有機基で置換されている界面活性剤を用いると臨界表面エネルギーを１０〜５５ｄｙｎ／ｃｍの範囲で極めて簡単に制御できた。
【００４１】
また、非水系の有機溶媒として、アルキル基、ふっ化炭素基または塩化炭素基またはシロキサン基を含む溶媒を用いると未反応の界面活性剤を効率よく除去できた。
【００４２】
このとき、ＣＨ₃（ＣＨ₂）₁₄ＳｉＣｌ₃とＣ₆Ｈ₅ＣＨ＝ＣＨＣＯＣ₆Ｈ₄Ｏ（ＣＨ₂）₆ＳｉＣｌ₃の組成を１：０〜０：１（好ましくは５０：１〜１：５０）で変えると、臨界表面エネルギーは２４ｍＮ／ｍから３５ｍＮ／ｍに変化し、それぞれプレチルト角は８６゜から３゜の範囲で任意に制御できた。さらに、ＣＨ₃（ＣＨ₂）₁₄ＳｉＣｌ₃の代わりに化学吸着化合物としてフッ素を含む界面活性剤、例えば、ＣＦ₃（ＣＦ₂）₇（ＣＨ₂）₂ＳｉＣｌ₃を添加して行くと臨界表面エネルギーは１４ｍＮ／ｍまで小さくできた。２０重量％添加の場合は、液晶のプレチルト角はほぼ９０度であったが、電圧を印加して駆動してみると、きわめて均一な配向変化を示した。
【００４３】
なお、膜を基板表面に選択的に形成したい場合には、オフセット印刷、スクリーン印刷、またはロールコート法を用いて所望のパターンで基板表面１に吸着液２を塗布する方法が利用できた。
【００４４】
以上のように、実施例１では、炭素鎖長が−（ＣＨ₂）₁₄−のシラン系界面活性剤と−（ＣＨ₂）₆−で感光性基を有するシラン系界面活性剤とを混合して用いたが、炭素鎖長の長さが異なる（例えば、−（ＣＨ₂）_n−；ｎは１から２５の範囲の整数）界面活性剤を混合して用いても、配向方向は偏光方向で制御でき、プレチルト角度は単分子膜の臨界表面エネルギーで同様に制御できた。また炭化水素鎖の代わりにシロキサン結合鎖（−（ＳｉＯ）_n−；ｎは１から１５の範囲の整数）を組み込んでも同様の配向制御が可能であった。
【００４５】
なお、上記実施例２では、露光に用いる光として超高圧水銀灯のｉ線である３６５ｎｍの光を用いたが、膜物質の光の吸収度合いに応じて４３６ｎｍ、４０５ｎｍ、２５４ｎｍやＫｒＦエキシマレーザーで得られる２４８ｎｍの光を用いることも可能である。特に、２４８ｎｍや２５４ｎｍの光は大部分の物質に吸収され易いためエネルギー配向効率が高い。
【００４６】
（実施例３）
実施例１に於て、炭素鎖やシロキサン結合鎖を含む界面活性剤分子の化学吸着を行う工程の前に、ドライ雰囲気中（相対湿度３０％以下）でクロロシリル基を複数個含む化合物を溶かして作製した吸着溶液を作り、基板表面に塗布し乾燥した。すると、吸着溶媒が蒸発しクロロシリル基を複数個含む化合物は濃縮され、ついにはクロロシリル基を複数個含む化合物の皮膜が形成された。このとき、基板表面に含まれた水酸基とクロロシリル基を複数個含む化合物のクロロシリル基が急速に脱塩酸反応する。その後、さらに水分をほとんど含まない非水系の有機溶媒で洗浄し、空気中に取り出すと、基板表面に残ったクロロシリル基が空気中の水分と反応して、表面にＳｉＯＨ結合、すなわち水酸基を多数含む無機シロキサンから成る化学吸着単分子膜が形成された。
【００４７】
たとえば、クロル基を複数個含むシリル化合物としてＣｌ₃ＳｉＯＳｉＣｌ₃を用い脱水したトルエンに１重量％溶かして吸着液を作製し、乾燥雰囲気中で基板を１分程度浸漬し、さらに引き上げて同雰囲気中で５分間程度かけて乾燥しトルエンを蒸発させてからさらに５分反応させた後よく脱水したクロロホルムで洗浄すると、基材表面には−ＯＨ基が多少とも含まれているので、界面で脱塩酸反応が生じ図８に示したような単分子膜状の被膜１１が、−ＳｉＯ−結合を介して基板表面に形成された。その後さらに空気中に取り出し、空気中の水分と反応させると図９に示したような表面に水酸基（−ＯＨ）を多数含む単分子膜状のシロキサン被膜１２が−ＳｉＯ−結合を介して基板表面に形成された。
【００４８】
前記の一連の化学吸着単分子膜形成工程において、溶媒蒸発後には前記クロル基を複数個含むシリル化合物が１００％に濃縮された状態で基板表面に塗布されたことになり、その状態でクロロシラン系界面活性剤のＳｉＣｌ基と前記基板表面の水酸基とで脱塩酸反応が生じるので、通常１〜２時間必要とする化学吸着時間が、１１分間と極めて短時間に短縮できた。
【００４９】
なお、このときできたシロキサン単分子膜１２は基板とは−ＳｉＯ−の化学結合を介して完全に結合されているので剥がれることが無い。また、得られた単分子膜は表面にＳｉＯＨ結合を数多く持つ。特に−ＯＨ基は、当初の約２〜３倍程度の数が生成された。この状態での処理部は、極めて親水性が高かった。
【００５０】
そこで、この状態で、実施例１と同様の界面活性剤を用い化学吸着工程を行うと、図１の４と同様、ＣＦ₃（ＣＦ₂）₇（ＣＨ₂）₂ＳｉＣｌ₃界面活性剤が反応してなる炭素鎖を含む化学吸着単分子膜が前記シロキサン単分子膜１２を介してシロキサンの共有結合で化学結合した状態で約１．８ｎｍの膜厚で形成された。このとき、界面活性剤の吸着前の基材表面の吸着サイト（この場合はＯＨ基）は、実施例１に比べて約２〜３倍程度と多いため、実施例１の場合に比べより吸着分子密度を大きくできた。また、処理部は極めて撥油性が高かった。
【００５１】
なお、クロル基を複数個含むシリル化合物として、前記Ｃｌ₃ＳｉＯＳｉＣｌ₃以外にＣｌ−（ＳｉＣｌ₂Ｏ）_n−ＳｉＣｌ₃（ｎは整数。ただし０，１〜３が扱いよかった。）が利用できた。
【００５２】
（参考例１）
実施例２に於て、化学吸着物質としてＣＨ₃（ＣＨ₂）₁₄ＳｉＣｌ₃の代わりに、ＣｌＳｉ（ＣＨ₃）₂ＯＳｉ（ＣＨ₃）₂ＯＳｉ（ＣＨ₃）₂ＯＳｉ（ＣＨ₃）₂Ｃｌを１：０〜０：１の間で混合して用いた場合、臨界表面エネルギーは混合比に応じて３７ｍＮ／ｍから２３ｍＮ／ｍの範囲で制御できた。
【００５３】
（実施例４）
実施例２に於て、化学吸着物質としてＣＨ₃（ＣＨ₂）₁₄ＳｉＣｌ₃の代わりに、ＣＨ₃ＣＨ₂Ｃ^*ＨＣＨ₃ＣＨ₂ＯＣＯ（ＣＨ₂）₁₀ＳｉＣｌ₃（ただし、Ｃ^*は不整炭素）を１：０〜１：２０の間で混合して用い同様の配向膜を作製した。この場合には、臨界表面エネルギーは混合比に応じて３１ｍＮ／ｍから４１ｍＮ／ｍの範囲で制御できた。
【００５４】
【発明の効果】
以上説明した通り、本発明によれば、厚みはナノメータレベルできわめて薄く、膜厚均一性に優れた化学吸着単分子膜を極めて短時間で、高効率に形成できる効果がある。
【図面の簡単な説明】
【図１】本発明の実施例１における単分子膜作製に用いる化学吸着工程を説明するための断面概念図。
【図２】同、単分子膜作製の洗浄工程を説明するための断面概念図。
【図３】同、溶媒洗浄後のフッ素系単分子膜内の分子配向状態を説明するために断面を分子レベルまで拡大した概念図。
【図４】本発明の実施例２における感光性基を組み込んだ単分子膜内の分子配向状態を説明するために断面を分子レベルまで拡大した概念図。
【図５】同、光露光により吸着された分子を再配向させるために用いた露光工程の概念図。
【図６】同、光配向後の単分子膜内の分子配向状態を説明するための概念図。
【図７】同、光配向後の化学吸着単分子膜の分子配向状態を説明するために断面を分子レベルまで拡大した概念図。
【図８】本発明の実施例３におけるクロロシラン単分子膜の形成された状態（空気中の水分との反応前）を説明するために分子レベルまで拡大した断面概念図。
【図９】本発明の実施例３におけるシロキサン単分子膜の形成された状態を説明するために分子レベルまで拡大した断面概念図。
【符号の説明】
１基板
２化学吸着液
３洗浄用非水系溶媒
４フッ素系化学吸着単分子膜
４’ １次配向された感光性基を有する化学吸着単分子膜
４” 再配向された感光性基が重合された化学吸着単分子膜
５洗浄液からの引き上げ方向
６偏光板
７照射光
８再配向方向
９透明電極
１１単分子膜状のクロロシラン被膜
１２単分子膜状のシロキサン被膜
１３偏光方向[0001]
BACKGROUND OF THE INVENTION
The present invention is related to method for producing a chemically adsorbed monomolecular film. More specifically, the present invention relates to a method for producing a chemical adsorption monomolecular film which is a thin film material used at a molecular level, such as a fluorine-based antifouling monomolecular film, an alignment film for liquid crystal, a polarizing film, a retardation film, and a conductive film for molecular elements .
[0002]
[Prior art]
Conventionally, as a method for producing a chemical adsorption monomolecular film, a substrate is immersed in a chemical adsorption solution, and the chemical adsorption material and substrate in the solvent are contacted at the contact surface between the substrate surface and the chemical adsorption solution. A method of causing a chemical reaction between material surfaces for a predetermined time has been generally used.
[0003]
For example, a silane-based surfactant containing a linear hydrocarbon group and Si (hereinafter also referred to as a chemical adsorption material or a chemical adsorption compound) is used and dissolved in a non-aqueous solvent at a concentration of about 1% by weight for chemical adsorption. Prepare the solution, immerse the base material in this chemical adsorption solution, let the chemical adsorption reaction for a predetermined time in the chemical adsorption solution, take out the base material from the chemical adsorption solution, and remove the extra chemical adsorption attached to the surface A method of washing and removing the liquid with a non-aqueous organic solvent has been used.
[0004]
[Problems to be solved by the invention]
However, when a conventional method for producing a chemical adsorption monomolecular film is carried out at a concentration of about 1% by weight at room temperature, it takes about 2 hours until the reaction is saturated, which is very inefficient. Therefore, as a method for shortening the reaction time, a method of increasing the concentration of the chemical adsorption solution or a method of increasing the temperature during chemical adsorption has been tried. However, the heating method has a limit of about 50 to 60 ° C., and this level of heating can shorten the reaction time only by about 10 to 20%. Further, when the chemical adsorption is carried out by further heating, there is a problem that the solvent evaporates during the adsorption reaction or the orientation of the chemisorbed monomolecular film is deteriorated. On the other hand, in the method of increasing the concentration, an expensive chemisorbed substance is wasted and the efficiency is poor. Moreover, it was inconvenient in terms of the stability of the prepared chemical adsorption solution.
[0005]
In order to solve the above-mentioned conventional problems, an object of the present invention is to provide a method capable of producing a uniform chemisorbed monomolecular film in a short time and with high efficiency at a nanometer level.
[0006]
[Means for Solving the Problems]
The method for producing a chemisorbed monomolecular film according to the present invention that achieves the above-described object comprises:
A step of applying a chemisorption liquid containing a silicone-based non-aqueous organic solvent having a boiling point of 100 to 250 ° C. and a silane-based surfactant having a SiCl ₃ group to a substrate having an OH group on the surface in a dry atmosphere. ,
While evaporating the organic solvent in a dry atmosphere and concentrating it, the silane-based surfactant molecules in the adsorbed liquid are chemically reacted with OH groups on the substrate surface to cause the silane-based surfactant molecules to be A step of fixing at one end to the substrate surface;
Thereafter, using an organic solvent, washing and removing unreacted silane-based surfactant remaining on the substrate surface in a dry atmosphere; and
Exposing the substrate surface to moisture;
Have
[0007]
Between the step of washing and removing and the step of exposing the substrate surface to moisture, the substrate is further erected in a desired direction to drain the cleaning solution, and the silane-based surfactant molecules fixed in the direction of draining are fixed. A step of orienting may also be included.
[0008]
Further, when an atmosphere having a relative humidity of 30% or less is used as a dry atmosphere, it is convenient to produce a more complete chemisorption monomolecular film without white turbidity .
[0009]
Furthermore, the terminal or part of the carbon chain or siloxane bond chain is a carbon trifluoride group (—CF ₃ ), a methyl group (—CH ₃ ), a vinyl group (—CH═CH ₂ ), an allyl group (—CH ₃ ). ═CH—), acetylene group (carbon-carbon triple bond), phenyl group (—C ₆ H ₅ ), aryl group (—C ₆ H ₄ —), halogen atom, alkoxy group (—OR; R is alkyl represents a group), a cyano group (-CN), mosquito carbonyl group (= CO), and the carboxy group (-COO-) or it is substituted with at least one organic group selected, with a variety of surface energy It is convenient to produce a chemisorbed monolayer.
[0010]
Furthermore, when a mixture of a plurality of types of silane surfactants is used as the surfactant, a monomolecular film whose surface is uneven at the molecular level can be produced, which is advantageous in expressing a new function.
[0011]
On the other hand, if a photosensitive group is incorporated into the chemisorbed material, and after adsorption / washing, or after pre-orientation of the drained liquid, further exposure is performed through the polarizing plate, the chemisorbed molecules are aligned along the polarization direction. Moreover, since it is polymerized, it is convenient for producing a chemisorption monomolecular film in which molecules are oriented and fixed.
[0014]
Further, in the step of applying the chemical adsorption liquid, when an offset printing, screen printing, or roll coating method is used, the chemical adsorption liquid is not used more than necessary, so that a film can be formed more efficiently.
[0015]
In addition, when performing offset printing, screen printing, or roll coating in the process of applying the chemical adsorption liquid, the solvent evaporation time after application can be shortened by controlling the viscosity of the chemical adsorption liquid to 1 to 50000 cSt. In addition, it is convenient to prevent dripping. Furthermore, when silicone is used for controlling the viscosity of the chemical adsorption solution, it is advantageous that the viscosity can be controlled only by adjusting the molecular weight.
[0018]
【Example】
Hereinafter, the present invention will be described more specifically with reference to examples.
(Example 1)
A glass substrate 1 (having many hydroxyl groups on the surface) having a transparent electrode formed on the surface was prepared and thoroughly washed and degreased in advance. On the other hand, a silane-based surfactant (hereinafter referred to as a chemical adsorption material or a chemical adsorption compound) containing a linear hydrocarbon group and Si containing one functional group (such as —CF ₃ ) that reduces the surface energy of the coating at the end. say), using _{_{_{CF 3 (CF 2) 7 (}}} CH 2) 2 SiCl 3, had been prepared chemisorption solution by dissolving in a concentration of 1% by weight of non-aqueous solvents. At this time, as a non-aqueous solvent (a solvent not containing water), a well-dehydrated hexamethyl silicone (bp. 100 ° C., in addition to this, a non-aqueous organic solvent having a boiling point up to about 250 ° C. has a slightly longer evaporation time. However, it was practically usable without any problem. The solution thus prepared is used as the adsorption solution 2, and the substrate 1 may be immersed in the adsorption solution 2 for about 1 minute (in a coater or the like) in a dry atmosphere (relative humidity of 30% or less). (FIG. 1). Thereafter, the solution was pulled up from the solution, the silicone solvent was evaporated in the same atmosphere, concentrated until the chemical adsorption substance concentration on the substrate surface reached 100%, and then reacted for another 10 minutes. That is, a film made of only the chemical adsorption material was formed on the substrate surface to a thickness of about 5 μm to accelerate the reaction between the chemical adsorbent and the substrate surface. Thereafter, after washing with chloroform 3 which is a non-aqueous solvent that does not contain water well dehydrated in a similar dry atmosphere, it was pulled up from the washing solution, drained, and then exposed to moisture-containing air (FIG. 2). ). Reference numeral 5 denotes a pulling direction from the cleaning liquid.
[0019]
By the above treatment, the chemisorption monomolecular film 4 obtained by the reaction of the chlorosilane-based surfactant is about 1 nm in a state where it is chemically bonded to the portion containing the hydroxyl group on the substrate surface via a covalent bond of siloxane. Formed in thickness. At this time, the critical surface energy of the chemisorbed film was about 10 mN / m as measured using the Zisman plot. Moreover, the contact angle with water was about 120 degrees, and a chemisorption monomolecular film excellent in antifouling property was obtained.
[0020]
Incidentally, in the reaction between the substrate surface and the surfactant, a bond of the following formula (Chemical Formula 1) is first generated, and when taken out in general air after solvent cleaning, it reacts with moisture in the air to formula (Chemical Formula). It was thought that the bond of 2) was generated. The carbon chains of the molecules adsorbed at this time were oriented with a certain degree of inclination in the liquid draining direction (the direction opposite to the pulling direction 5 from the cleaning liquid) when analyzed by FTIR (FIG. 3).
[0021]
[Chemical 1]

[0022]
[Chemical 2]

[0023]
Furthermore, the peel strength was confirmed by a cross-cut test, but it did not peel at all.
In the series of chemical adsorption monomolecular film forming steps, after evaporation of the solvent, the chlorosilane-based surfactant is applied to the substrate surface in a state of being concentrated to 100%. In that state, the chlorosilane-based surfactant is applied. Since the dehydrochlorination reaction occurs between the SiCl group and the hydroxyl group on the surface of the substrate, the adsorption time usually required for 1 to 2 hours can be shortened to an extremely short time of 11 minutes.
[0024]
(Example 2)
A glass substrate with a transparent electrode formed on the surface (containing a large number of hydroxyl groups on the surface) was prepared and thoroughly washed and degreased in advance. On the other hand, a silane-based surfactant (hereinafter also referred to as a chemical adsorption material or a chemical adsorption compound) containing a linear hydrocarbon group and Si incorporating one functional group for controlling the surface energy of the coating at the terminal, CH ₃ ( CH ₂ ) ₁₄ SiCl ₃ and a silane-based surfactant incorporating a photosensitive group, C ₆ H ₅ CH═CHCOC ₆ H ₄ O (CH ₂ ) ₆ SiCl ₃ (used by mixing at a molar ratio of 1: 1) A chemisorption solution was prepared by dissolving in a non-aqueous solvent at a concentration of 1% by weight. At this time, as a non-aqueous solvent (a solvent not containing water), a well-dehydrated octamethyl silicone (bp. 100 ° C., other than this, a non-aqueous organic solvent having a boiling point up to about 250 ° C. has a slightly longer evaporation time. However, it was practically usable without any problem. The solution thus prepared was used as an adsorption solution, and the substrate was immersed (applied) in the adsorption solution 2 for about 1 minute in a dry atmosphere (relative humidity of 30% or less).
[0025]
Thereafter, the solution was pulled up from the solution, the silicone solvent was evaporated in the same atmosphere, concentrated until the chemical adsorption substance concentration on the substrate surface reached 100%, and then reacted for another 5 minutes. That is, a film made only of the chemical adsorption material was formed on the substrate surface to accelerate the reaction between the chemical adsorption agent and the substrate surface. After washing with n-hexane, which is a non-aqueous solvent that does not contain water well dehydrated in a similar dry atmosphere, the substrate is pulled up from the cleaning solution in a desired state and drained. , Exposed to moisture-containing air.
[0026]
As a result of the above treatment, the chemisorbed monomolecular film 4 ′ formed by the reaction of the mixed chlorosilane-based surfactant is bonded in a state of being chemically bonded to the portion containing the hydroxyl group on the substrate surface via a covalent bond of siloxane. The bonded molecules are oriented in the direction opposite to the pulling direction 5, that is, along the liquid draining direction, and are formed with a film thickness of about 1.7 nm. At this time, the critical surface energy of the chemical adsorption film was about 28 mN / m.
[0027]
Therefore, using two substrates in this state, combining them so that the chemisorbed films face each other and setting the alignment direction to be antiparallel, a 20 micron gap liquid crystal cell is assembled, and nematic liquid crystal (ZLI4792; manufactured by Merck) When the alignment state was confirmed by injecting the liquid crystal, the injected liquid crystal molecules were aligned at a pretilt angle of 4 ° with respect to the substrate in the direction of draining the cleaning liquid. By the way, in the reaction between the substrate surface and the surfactant, the bonds of the following formulas (Chemical Formulas 3 and 4) are first formed in a ratio of approximately 1: 1, and further, when taken out in general air after solvent cleaning, It was considered that the bond of the formulas (Chemical Formulas 5 and 6) was generated by reacting with the water. The carbon chains of the molecules adsorbed at this time were oriented with a certain degree of inclination in the liquid draining direction when analyzed by FTIR (FIG. 4).
[0028]
[Chemical 3]

[0029]
[Formula 4]

[0030]
[Chemical formula 5]

[0031]
[Chemical 6]

[0032]
In the series of chemical adsorption monomolecular film forming steps, after evaporation of the solvent, the chlorosilane-based surfactant is applied to the substrate surface in a state of being concentrated to 100%. In that state, the chlorosilane-based surfactant is applied. Since the dehydrochlorination reaction occurs between the SiCl group and the hydroxyl group on the surface of the substrate, the adsorption time usually required for 1 to 2 hours can be shortened to an extremely short time of 6 minutes.
[0033]
Next, two substrates in this state are prepared, and are further shifted by 3 degrees from the direction perpendicular to the respective pulling directions, that is, the polarizing plate 6 ( HNP'B: manufactured by Polaroid Co., Ltd. was placed over the substrate and irradiated with 400 mJ using 365 nm (i-line) light 7 (3.6 mW / cm ² after passing through the polarizing film) of a 500 W ultrahigh pressure mercury lamp (Fig. 5). FIG. 6 shows a chemisorption monomolecular film excluding the polarizing plate 6 after irradiation. In FIG. 6, 8 indicates the reorientation direction of the film molecules.
According to the above treatment, according to FTIR analysis, the molecule represented by chemical formula ₅ in the chemisorption monomolecular film is not changed, but the photosensitive group represented by chemical formula ₆ (C ₆ H ₅ CH═CHCOC ₆ H ₄ —) is 365 nm. Since it showed photosensitivity to (i-line) light, it was photopolymerized to give a structure as shown in Chemical Formula 7. 5-6, 9 represents a transparent electrode. The structure of the membrane molecule is shown in FIG. In FIG. 7, 4 ″ represents a chemisorbed monomolecular film in which a reoriented photosensitive group is polymerized.
[0034]
[Chemical 7]

[0035]
Furthermore, using two substrates in this state, the chemical adsorption film 4 ″ of FIG. 7 is combined so as to face each other, and the alignment direction is set to be antiparallel, and a 20-micron gap liquid crystal cell is assembled, and a nematic liquid crystal (ZLI4792) is assembled. ; Manufactured by Merck & Co., Inc.) and the alignment state was confirmed. The injected liquid crystal molecules were aligned at a pretilt angle of 4 ° with respect to the substrate along the polarization direction.
[0036]
Incidentally, when the orientation direction of the linear carbon chain in the chemisorption monomolecular film 4 ′ is analyzed using FTIR, the critical surface energy and the tilt angle are not changed, but the orientation direction 8 is substantially parallel to the polarization direction 13. In addition, the orientation variation was improved as compared with the preliminary orientation for liquid draining by pulling up.
[0037]
At this time, in order to align the orientation direction of the adsorbed molecules in the irradiation part in one direction, it is necessary to shift the orientation direction of the adsorbed molecules to a certain direction, rather than completely intersecting the liquid draining direction at 90 °, and preferably slightly. If they are completely crossed at 90 °, individual molecules may be oriented in two directions. In addition, when the polarization direction 13 was adjusted so as to be parallel to the cleaning liquid draining direction, a monomolecular film having further excellent alignment regulating force was obtained.
[0038]
In addition, when it is desired to selectively change the orientation direction on the substrate surface, after performing the pulling up of the liquid in advance, a pattern mask is superimposed on the polarizing plate and irradiated with ultraviolet rays having a wavelength of 365 nm at an energy of 200 to 500 mJ. A plurality of portions in which the alignment direction is changed only in the irradiated portion and the alignment directions are different in a pattern in the alignment film in the same plane, that is, a portion where the liquid crystal is aligned along the pulling liquid draining direction 5 and the polarization direction 13 respectively. I was able to provide a place.
[0039]
When an atmosphere having a relative humidity of 35% or more was used as the dry atmosphere, a white coating remained on the substrate surface even after cleaning, and could not be easily removed.
Moreover, although the silane type surfactant containing a linear carbon chain or a siloxane bond chain and a chlorosilyl group was used as the surfactant, the reaction rate of a surfactant containing an alkoxysilane group or an isocyanate silane group is slightly slow. But it was available.
[0040]
Furthermore, as a surfactant, a plurality of types of silicon surfactants having different critical surface energies, for example, a terminal or a part of a carbon chain or a siloxane bond chain may be a carbon trifluoride group (—CF ₃ ), a methyl group (— CH ₃ ), vinyl group (—CH═CH ₂ ), allyl group (—CH═CH—), acetylene group (carbon-carbon triple bond), phenyl group (—C ₆ H ₅ ), aryl group (— . C ₆ H ₄ -), a halogen atom, an alkoxy group (-OR; R is an alkyl group, a range of 1 to 3 carbon atoms is preferred), cyano group (-CN), amino group (-NH _2), When a surfactant substituted with at least one organic group selected from a hydroxyl group (—OH), a carbonyl group (═CO), a carboxy group (—COO—) and a carboxyl group (—COOH) is used, the critical surface energy is reduced. 10 It could be very easily controlled in the range of 5dyn / cm.
[0041]
Further, when a solvent containing an alkyl group, a carbon fluoride group, a carbon chloride group or a siloxane group was used as the non-aqueous organic solvent, the unreacted surfactant could be efficiently removed.
[0042]
At this time, the composition of CH ₃ (CH ₂ ) ₁₄ SiCl ₃ and C ₆ H ₅ CH═CHCOC ₆ H ₄ O (CH ₂ ) ₆ SiCl ₃ is set to 1: 0 to 0: 1 (preferably 50: 1 to 1: 50), the critical surface energy changed from 24 mN / m to 35 mN / m, and the pretilt angle could be arbitrarily controlled in the range of 86 ° to 3 °. Furthermore, when a surfactant containing fluorine as a chemisorbing compound instead of CH ₃ (CH ₂ ) ₁₄ SiCl ₃ , for example, CF ₃ (CF ₂ ) ₇ (CH ₂ ) ₂ SiCl ₃ is added, the critical surface energy is increased. Can be reduced to 14 mN / m. In the case of 20% by weight addition, the pretilt angle of the liquid crystal was approximately 90 degrees, but when it was driven by applying a voltage, it showed a very uniform alignment change.
[0043]
In addition, when it was desired to selectively form the film on the substrate surface, a method of applying the adsorbing liquid 2 to the substrate surface 1 in a desired pattern using offset printing, screen printing, or roll coating method could be used.
[0044]
As described above, in Example 1, a silane surfactant having a carbon chain length of — (CH ₂ ) ₁₄ — and a silane surfactant having a photosensitive group of — (CH ₂ ) ₆ — are mixed. Although the carbon chain length is different (for example, — (CH ₂ ) _n —; n is an integer in the range of 1 to 25), the orientation direction is the polarization direction even if a surfactant is mixed. The pretilt angle could be similarly controlled by the critical surface energy of the monomolecular film. In addition, the same orientation control was possible by incorporating a siloxane bond chain (— (SiO) _n —; n is an integer in the range of 1 to 15) instead of the hydrocarbon chain.
[0045]
In Example 2 above, 365 nm light, i-line of an ultrahigh pressure mercury lamp, was used as light used for exposure, but it was obtained with a 436 nm, 405 nm, 254 nm or KrF excimer laser depending on the light absorption degree of the film material. It is also possible to use 248 nm light. In particular, light of 248 nm and 254 nm has high energy alignment efficiency because it is easily absorbed by most substances.
[0046]
(Example 3)
In Example 1, a compound containing a plurality of chlorosilyl groups was dissolved in a dry atmosphere (with a relative humidity of 30% or less) before the step of chemical adsorption of surfactant molecules containing carbon chains or siloxane bond chains. The produced adsorption solution was made, applied to the substrate surface and dried. Then, the adsorption solvent was evaporated and the compound containing a plurality of chlorosilyl groups was concentrated, and finally a film of a compound containing a plurality of chlorosilyl groups was formed. At this time, the chlorosilyl group of the compound containing a plurality of hydroxyl groups and chlorosilyl groups contained on the substrate surface rapidly undergoes a dehydrochlorination reaction. After that, when the substrate is further washed with a non-aqueous organic solvent containing almost no moisture and taken out into the air, the chlorosilyl group remaining on the substrate surface reacts with the moisture in the air and contains a lot of SiOH bonds, that is, hydroxyl groups on the surface. A chemisorbed monolayer composed of inorganic siloxane was formed.
[0047]
For example, an adsorption solution is prepared by dissolving 1% by weight in dehydrated toluene using Cl ₃ SiOSiCl ₃ as a silyl compound containing a plurality of chloro groups, dipping the substrate for about 1 minute in a dry atmosphere, and further raising the substrate in the same atmosphere. After drying for 5 minutes and evaporating toluene, reacting for another 5 minutes and washing with well-dehydrated chloroform, the substrate surface contains some -OH groups. As a result of the reaction, a monomolecular film 11 as shown in FIG. 8 was formed on the substrate surface via —SiO— bonds. After that, when it is further taken out into the air and reacted with moisture in the air, the monomolecular film-like siloxane film 12 containing many hydroxyl groups (—OH) on the surface as shown in FIG. Formed.
[0048]
In the series of chemical adsorption monomolecular film forming steps, after evaporation of the solvent, the silyl compound containing a plurality of chloro groups is applied to the substrate surface in a state of being concentrated to 100%. Since the dehydrochlorination reaction occurs between the SiCl group of the surfactant and the hydroxyl group on the surface of the substrate, the chemical adsorption time that normally requires 1 to 2 hours can be shortened to an extremely short time of 11 minutes.
[0049]
The siloxane monomolecular film 12 formed at this time is not peeled off because it is completely bonded to the substrate through a —SiO— chemical bond. Moreover, the obtained monomolecular film has many SiOH bonds on the surface. In particular, the number of —OH groups was about 2 to 3 times as many as the original. The treated part in this state was extremely hydrophilic.
[0050]
Therefore, in this state, when the chemical adsorption process is performed using the same surfactant as in Example 1, the CF ₃ (CF ₂ ) ₇ (CH ₂ ) ₂ SiCl ₃ surfactant reacts as in 4 of FIG. A chemically adsorbed monomolecular film containing carbon chains formed as described above was formed with a film thickness of about 1.8 nm in a state of being chemically bonded by a siloxane covalent bond via the siloxane monomolecular film 12. At this time, the number of adsorption sites (OH groups in this case) on the surface of the base material before adsorption of the surfactant is about 2 to 3 times as large as that in Example 1, so that the adsorption site is larger than that in Example 1. The molecular density could be increased. In addition, the treated part was extremely high in oil repellency.
[0051]
In addition to the above Cl ₃ SiOSiCl ₃ , Cl— (SiCl ₂ O) _n —SiCl ₃ (n is an integer, although 0, 1 to ₃ can be handled) can be used as the silyl compound containing a plurality of chloro groups. .
[0052]
( Reference Example 1 )
In Example 2, instead of CH ₃ (CH ₂ ) ₁₄ SiCl ₃ , ClSi (CH ₃ ) ₂ OSi (CH ₃ ) ₂ OSi (CH ₃ ) ₂ OSi (CH ₃ ) ₂ Cl was used instead of CH ₃ (CH ₂ ) ₁₄ SiCl _3. When mixed between 1: 0 and 0: 1, the critical surface energy could be controlled in the range of 37 mN / m to 23 mN / m depending on the mixing ratio.
[0053]
(Example 4 )
In Example 2, instead of CH ₃ (CH ₂ ) ₁₄ SiCl ₃ as a chemisorbing material, CH ₃ CH ₂ C ^* HCH ₃ CH ₂ OCO (CH ₂ ) ₁₀ SiCl ₃ (where C ^* is an irregular carbon) ) Were mixed between 1: 0 and 1:20 to produce a similar alignment film. In this case, the critical surface energy could be controlled in the range of 31 mN / m to 41 mN / m depending on the mixing ratio.
[0054]
【The invention's effect】
As described above, according to the present invention, the thickness is extremely thin at the nanometer level, and there is an effect that a chemical adsorption monomolecular film excellent in film thickness uniformity can be formed in a very short time with high efficiency.
[Brief description of the drawings]
FIG. 1 is a conceptual cross-sectional view for explaining a chemical adsorption step used for production of a monomolecular film in Example 1 of the present invention.
FIG. 2 is a conceptual cross-sectional view for explaining a cleaning process for producing a monomolecular film.
FIG. 3 is a conceptual diagram in which a cross section is enlarged to a molecular level in order to explain a molecular orientation state in a fluorine-based monomolecular film after solvent cleaning.
FIG. 4 is a conceptual diagram in which a cross section is expanded to a molecular level in order to explain a molecular orientation state in a monomolecular film incorporating a photosensitive group in Example 2 of the present invention.
FIG. 5 is a conceptual diagram of an exposure process used for reorienting molecules adsorbed by light exposure.
FIG. 6 is a conceptual diagram for explaining a molecular orientation state in a monomolecular film after photo-alignment.
FIG. 7 is a conceptual diagram in which the cross section is expanded to the molecular level in order to explain the molecular orientation state of the chemisorbed monomolecular film after photo-alignment.
FIG. 8 is a conceptual cross-sectional view enlarged to a molecular level in order to explain a state where a chlorosilane monomolecular film is formed (before reaction with moisture in the air) in Example 3 of the present invention.
FIG. 9 is a conceptual cross-sectional view enlarged to a molecular level for explaining a state where a siloxane monomolecular film is formed in Example 3 of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Substrate 2 Chemical adsorption liquid 3 Non-aqueous solvent 4 for washing | cleaning Fluorine type chemical adsorption monomolecular film | membrane 4 'Chemical adsorption monomolecular film | membrane 4 "which has the primary orientation photosensitive group 4" The reoriented photosensitive group was polymerized Chemical adsorption monomolecular film 5 Lifting direction from cleaning liquid 6 Polarizing plate 7 Irradiation light 8 Reorientation direction 9 Transparent electrode 11 Monomolecular film-like chlorosilane film 12 Monomolecular film-like siloxane film 13 Polarization direction

Claims

And an organic solvent silicone nonaqueous boiling point 100 to 250 ° C., applying a chemisorption solution containing a silane-based surfactant having an SiCl ₃ group, the board having an OH group on the surface in a dry atmosphere process you,
While concentrating the organic solvent is evaporated in a dry atmosphere, the said silane-based surfactant molecules and OH groups of Cl to the substrate surface a silane-based surface active agent in the adsorbing solution have by chemical reaction A process of bonding and fixing to the substrate surface at one end;
Then, using an organic solvent, washing removes a silane-based surfactant unreacted remaining on the substrate surface in a dry atmosphere, and
Exposing the substrate surface to moisture;
A method for producing a chemisorbed monomolecular film comprising:

And an organic solvent silicone nonaqueous boiling point 100 to 250 ° C., applying a chemisorption solution containing a silane-based surfactant having an SiCl ₃ group, the board having an OH group on the surface in a dry atmosphere process you,
While concentrating the organic solvent is evaporated in a dry atmosphere, the said silane-based surfactant molecules and OH groups of Cl to the substrate surface a silane-based surface active agent in the adsorbing solution have by chemical reaction A process of bonding and fixing to the substrate surface at one end;
Then, using an organic solvent, washing removes a silane-based surfactant unreacted remaining on the substrate surface in a dry atmosphere,
A step of further upright the substrate to draining the washing liquid in a desired direction, is Oriented said silane-based surfactant molecules the fixed draining direction, and
Exposing the substrate surface to moisture;
A method for producing a chemisorbed monomolecular film comprising:

The method for producing a chemical adsorption monomolecular film according to any one of claims 1 and 2 , wherein an atmosphere having a relative humidity of 30% or less is used as a dry atmosphere.

The terminal or part of the carbon chain or siloxane bond chain is a carbon trifluoride group (—CF ₃ ), a methyl group (—CH ₃ ), a vinyl group (—CH═CH ₂ ), an allyl group (—CH═CH— ), Acetylene group (carbon-carbon triple bond), phenyl group (—C ₆ H ₅ ), aryl group (—C ₆ H ₄ —), halogen atom, alkoxy group (—OR; R represents an alkyl group) ), a cyano group (-CN), mosquito carbonyl group (= CO), and a carboxy group (-COO-) or al least any one of claim 1 to 3 which is substituted by one organic group selected The manufacturing method of the chemisorption monomolecular film of description.

Method of manufacturing a chemically adsorbed monomolecular film according to any one of claims 1-4 used as a mixture of double several silane-based surface active agent.

The method for producing a chemisorption monomolecular film according to any one of claims 1 to 5 , wherein a step of exposing through a polarizing plate is further performed after washing or liquid draining preliminary orientation.

The method for producing a chemical adsorption monomolecular film according to any one of claims 1 to 6 , wherein offset printing, screen printing, or roll coating is used in the step of applying the chemical adsorption solution.

The method for producing a chemical adsorption monomolecular film according to claim 7 , wherein the viscosity of the chemical adsorption liquid is controlled to 1 to 50000 cSt when performing offset printing, screen printing, or roll coating in the step of applying the chemical adsorption liquid.

The method for producing a chemical adsorption monomolecular film according to claim 8 , wherein silicone is added to control the viscosity of the chemical adsorption solution.