JP2004503832A - Multiphoton absorption method using patterned light - Google Patents

Abstract

Methods and apparatus for creating regions of at least partially reacted material in a photoreactive composition. The method includes providing a photoreactive composition; providing a source of light sufficient for the photoreactive composition to absorb at least two photons simultaneously; Providing an exposure system capable of inducing the following: generating a non-random three-dimensional light pattern by the exposure system; and exposing the photoreactive composition to the three-dimensional light pattern generated by the exposure system. Reacting at least partially a portion of the material in response to the non-random three-dimensional light pattern incident thereon.

Description

の式で示されるグリシジル・エーテル・モノマーがあり、この式で、Ｒ’はアルキル又はアリルであり、ｎは１〜６の範囲の整数である。例としては多水酸基を過剰な量のエピクロロヒドリンなどのクロロヒドリンと反応させて得られる多水酸基フェノールのグリシジル・エーテル（例えば、２，２−ｂｉｓ−（２，３−エポキシプロポキシフェノール）−プロパン）などがある。このタイプのエポキシドのさらに別の例は米国特許第３，０１８，２６２号に述べられており、さらに、Ｈａｎｄｂｏｏｋ　ｏｆ　Ｅｐｏｘｙ　Ｒｅｓｉｎｓ，Ｌｅｅ　ａｎｄ　Ｎｅｖｉｌｌｅ，ＭｃＧｒａｗ−Ｈｉｌｌ　Ｂｏｏｋ　Ｃｏ．，Ｎｅｗ　Ｙｏｒｋ（１９６７）でも参照できる。
【００６３】
多数の市販エポキシ樹脂も用いることができる。特に、入手し易いエポキシドには酸化アクタデシレン、エピクロロヒドリン、酸化スチレン、酸化ビニル・シクロヘキセン、グリシドル、グリシジルメタクリレン、ビスフェノールＡのジグリシル・エーテル（例えば、Ｒｅｓｏｌｕｔｉｏｎ　Ｐｅｒｆｏｒｍａｎｃｅ　Ｐｒｏｄｕｃｔｓ社、前Ｓｈｅｌｌ　Ｃｈｅｍｉｃａｌｓ　Ｃｏ．から発売されているＥｐｏｎ^ＴＭ８２８、Ｅｐｏｎ^ＴＭ８２５、Ｅｐｏｎ^ＴＭ１００４、及びＥｐｏｎ^ＴＭ１０１０など、及びＤｏｗ　Ｃｈｅｍｉｃａｌ　Ｃｏ．から発売されているＤＥＲ^ＴＭ−３３１、ＤＥＲ^ＴＭ−３３２及びＤＥＲ^ＴＭ−３３４など）、二酸化ビニルシクロヘキセン（例えばＵｎｉｏｎ　Ｃａｒｂｉｄｅ　Ｃｏｒｐ．から発売されているＥＲＬ−４２０６など）、３，４−エポキシシツキヘキシルメチル−３，４−エポキシシクロヘキセン・カルボキシレート（例えば、Ｕｎｉｏｎ　Ｃａｒｂｉｄｅ　Ｃｏｒｐから市販されているＥＲＬ−４２２１又はＣｙｒａｃｕｒｅ^ＴＭＵＶＲ　６１１０あるいはＵＶＲ　６１０５など）、３，４−エポキシ−６−メチルシクロヘキシルメチル−３，４−エポキシ−６−メチル−シクロヘキセン・カルボキシレート（例えばＵｎｉｏｎ　Ｃａｒｂｉｄｅ　ＣｏｒｐのＥＲＬ−４２０１）、ｂｉｓ（３，４−エポキシ−６−メチルシクロヘキシルメチル）アジペート（例えば、Ｕｎｉｏｎ　Ｃａｒｂｉｄｅ　ＣｏｒｐのＥＲＬ−４２８９）、ｂｉｓ（２，３−エポキシシクロペンチル）エーテル（例えば、Ｕｎｉｏｎ　Ｃａｒｂｉｄｅ　ＣｏｒｐのＥＲＬ−０４００）、ポリプロピレン・グリコールから修正された脂肪性エポキシ（例えばＵｎｉｏｎ　Ｃａｒｂｉｄｅ　ＣｏｒｐのＥＲＬ−４０５０及びＥＲＬ−４０５２）、二酸化ジペンテン（例えば、Ｕｎｉｏｎ　Ｃａｒｂｉｄｅ　ＣｏｒｐのＥＲＬ−４２６９）、エポキシ化ポリブタジエン（例えばＦＭＣ　ＣｏｒｐのＯｘｉｒｏｎ^ＴＭ２００１）、エポキシ機能性を有するシリコン樹脂、難燃性エポキシ樹脂（例えば、Ｄｏｗ　Ｃｈｅｍｉｃａｌ　Ｃｏから市販されているシュウ酸化ビビスフェノール・タイプのエポキシ樹脂であるＤＥＲ^ＴＭ−５８０）、フェノールアルデヒド・ノバラクの１，４−ブタンジオール・ジグリシル・エーテル（例えば、Ｄｏｗ　Ｃｈｅｍｉｃａｌ　ＣｏからのＤＥＮ^ＴＭ−４３１及びＤＥＮ^ＴＭ−４３８）、レソルチノル・ジグリシジル・エーテル（例えば、Ｋｏｐｐｅｒｓ　Ｃｏｍｐａｎｙ，Ｉｎｃ．からのＫｏｐｏｒｉｔｅ^ＴＭ）、ｂｉｓ（３，４−エポキシシクロヘキシル）アジペート（例えば、Ｕｎｉｏｎ　Ｃａｒｂｉｄｅ　ＣｏｒｐのＥＲＬ−４２９９あるいはＵＶＲ−６１２８）、２−（３，４−エポキシシクロヘキシル−５，５−スピロ−３，４−エポキシ）シクロヘキサン−メタ−ジオキサン（例えば、Ｕｎｉｏｎ　Ｃａｒｂｉｄｅ　ＣｏｒｐのＥＲＬ−４２３４）、一酸化ビニルシクロヘキセン１，２−エポキシヘキサデカン（例えば、Ｕｎｉｏｎ　Ｃａｒｂｉｄｅ　ＣｏｒｐのＵＶＲ−６２１６）、アルキルＣ_８−Ｃ_１０グリシル・エーテル（例えば、Ｒｅｓｏｌｕｔｉｏｎ　Ｐｅｒｆｏｒｍａｎｃｅ　ＰｒｏｄｕｃｔｓからのＨｅｌｏｘｙ^ＴＭ　Ｍｏｄｉｆｉｅｒ７）、アルキルＣ_１２−Ｃ_１４グリシル・エーテル（例えば、Ｒｅｓｏｌｕｔｉｏｎ　Ｐｅｒｆｏｒｍａｎｃｅ　ＰｒｏｄｕｃｔｓからのＨｅｌｏｘｙ^ＴＭ　Ｍｏｄｉｆｉｅｒ８）、ブチル・グリシジル・エーテル（例えば、Ｒｅｓｏｌｕｔｉｏｎ　Ｐｅｒｆｏｒｍａｎｃｅ　ＰｒｏｄｕｃｔｓからのＨｅｌｏｘｙ^ＴＭ　Ｍｏｄｉｆｉｅｒ６１）、クレシル・グリシジル・エーテル（例えば、Ｒｅｓｏｌｕｔｉｏｎ　Ｐｅｒｆｏｒｍａｎｃｅ　ＰｒｏｄｕｃｔｓからのＨｅｌｏｘｙ^ＴＭ　Ｍｏｄｉｆｉｅｒ６２）、ｐ−ｔｅｒｔ−ブチルフェニル・グリシジル・エーテル（例えば、Ｒｅｓｏｌｕｔｉｏｎ　Ｐｅｒｆｏｒｍａｎｃｅ　ＰｒｏｄｕｃｔｓからのＨｅｌｏｘｙ^ＴＭ　Ｍｏｄｉｆｉｅｒ６５）、１，４−ブタンジオールのグリシジル・エーテルなど多機能性グリシジル・エーテル（例えば、Ｒｅｓｏｌｕｔｉｏｎ　Ｐｅｒｆｏｒｍａｎｃｅ　ＰｒｏｄｕｃｔｓからのＨｅｌｏｘｙ^ＴＭ　Ｍｏｄｉｆｉｅｒ６７）、ネオペンチル・グリコールのグリシジル・エーテル（例えば、Ｒｅｓｏｌｕｔｉｏｎ　Ｐｅｒｆｏｒｍａｎｃｅ　ＰｒｏｄｕｃｔｓからのＨｅｌｏｘｙ^ＴＭ　Ｍｏｄｉｆｉｅｒ６８）、シクロヘキサンジメタノールのジグリシル・エーテル（例えば、Ｒｅｓｏｌｕｔｉｏｎ　Ｐｅｒｆｏｒｍａｎｃｅ　ＰｒｏｄｕｃｔｓからのＨｅｌｏｘｙ^ＴＭ　Ｍｏｄｉｆｉｅｒ１０７）、トリメチロル・エタン・エーテル（例えば、Ｒｅｓｏｌｕｔｉｏｎ　Ｐｅｒｆｏｒｍａｎｃｅ　ＰｒｏｄｕｃｔｓからのＨｅｌｏｘｙ^ＴＭ　Ｍｏｄｉｆｉｅｒ４４）、トリメチロール・プロパン・トリグリシル・エーテル（例えば、Ｒｅｓｏｌｕｔｉｏｎ　Ｐｅｒｆｏｒｍａｎｃｅ　ＰｒｏｄｕｃｔｓからのＨｅｌｏｘｙ^ＴＭ　Ｍｏｄｉｆｉｅｒ４８）、脂肪性ポリオールのポリグリシル・エーテル（例えば、Ｒｅｓｏｌｕｔｉｏｎ　Ｐｅｒｆｏｒｍａｎｃｅ　ＰｒｏｄｕｃｔｓからのＨｅｌｏｘｙ^ＴＭ　Ｍｏｄｉｆｉｅｒ８４）、ポリグリコール・ジエポキシド（例えば、Ｒｅｓｏｌｕｔｉｏｎ　Ｐｅｒｆｏｒｍａｎｃｅ　ＰｒｏｄｕｃｔｓからのＨｅｌｏｘｙ^ＴＭ　Ｍｏｄｉｆｉｅｒ３２）、ビスフェノールＦエポキシド（例えば、Ｃｉｂａ−Ｇｅｉｇｙ　Ｃｏｒｐ．から発売されているＥｐｏｎ^ＴＭ−１１３８あるいはＧＹ−２８１）、そして９，９−ｂｉｓ［４−（２，３−エポキシプロポキシ）−フェニル］フルオレノン（例えば、Ｒｅｓｏｌｕｔｉｏｎ　Ｐｅｒｆｏｒｍａｎｃｅ　Ｐｒｏｄｕｃｔｓ社のＥｐｏｎ^ＴＭ１０７９）などである。
【００６４】
他の有益なエポキシ樹脂には（グリシジルアクリレート及びグリシジルメタクリレートなどの）グリシドルのアクリル酸エステルの１つ、あるいは複数の共重合可能なビニル化合物などがある。そうしたコポリマーの例としては１：１スチレン−グリシジルメタクリレート、１：１メチルメタクリレート−グリシジルアクリレート、及び６２．５：２４：１３．５メチルメタクリレート−エチルアクリレート−グリシジルメタクリレートなどがある。他の有益なエポキシ樹脂も良く知られており、エピクロロヒドリン、アルキレン酸化物（例えば、酸化プロピレン）、酸化スチレン、アルケニル酸化物（例えば、酸化ブタジエン）、そしてグリシジル・エステル（例えば、エチル・グリシデート）などが含まれる。
【００６５】
有益なエポキシ機能性ポリマーには米国特許第４，２７９，７１７号（Ｅｃｋｂｅｒｇ）に述べられており、Ｇｅｎｅｒａｌ　Ｅｌｅｃｔｒｉｃ　Ｃｏｍｐａｎｙから市販されているようなものなどエポキシ機能性シリコンがある。これらはポリメチルシロキサンで、１〜２０モル％のケイ素原子がエポキシアルキル基（好ましくは、米国特許第５，７５３，３４６号（Ｋｅｓｓｅｌ）に述べられているようなエポキシ・シクロヘキシルエチル）で置換されたものである。
【００６６】
種々のエポキシ含有物質の混合物も用いることができる。こうした混合物はエポキシ含有化合物の２つ以上の重量平均分子量分布（例えば、低分子量（２００未満）、中間分子量（約２００〜１０，０００）、そして高分子量（約１０，０００超））を有している。あるいは、又はそれに加えて、エポキシ樹脂は異なった化学的性質（脂肪性及び芳香性など）あるいは機能性（極性及び非極性）を有するエポキシ含有物質の混合物を含んでいてもよい。その他の陽イオン反応性ポリマー（例えばビニル・エーテルなど）も必要であれば加えることができる。
【００６７】
好ましいエポキシには芳香性グリシジル・エポキシド（例えばＲｅｓｏｌｕｔｉｏｎ　Ｐｅｒｆｏｒｍａｎｃｅ　Ｐｒｏｄｕｃｔｓ社から市販されているＥｐｏｎ^ＴＭなど）及び環式脂肪性エポキシ（Ｕｎｉｏｎ　Ｃａｒｂｉｄｅ社発売のＥＲＬ−４２２１及びＥＲＬ−４２９９など）がある。
【００６８】
適切な陽イオン反応種も、ビニル・エーテル・モノマー、オリゴマー、そして反応性ポリマー（例えば、メチル・ビニル・エーテル、エチル・ビニル・エーテルｔｅｒｔ−ブチル・ビニル・エーテル、イソブチル・ビニル・エーテル、トリエチレングリコール・ジビニル・エーテル（Ｉｎｔｅｒｎａｔｉｏｎｌ　Ｓｐｅｃｉａｌｉｔｙ　Ｐｒｏｄｕｃｔｓ，Ｗａｙｎｅ，ＮＪから市販されているＲａｐｉ−Ｃｕｒｅ^ＴＭ　ＤＶＥ−３）、トリメチロルプロパン・トリビニル・エーテル（Ｂａｓｅ　Ｃｏｒｐ．，Ｍｏｕｎｔ　Ｏｌｉｖｅ，ＮＪから市販されているＴＭＰＴＶＥ）、そしてＡｌｌｉｅｄ　Ｓｉｇｎａｌ社発売のＶｅｃｔｏｍｅｒ^ＴＭジビニル・エーテル樹脂（例えば、Ｖｅｃｔｏｍｅｒ^ＴＭ２０１０、Ｖｅｃｔｏｍｅｒ^ＴＭ２０２０、Ｖｅｃｔｏｍｅｒ^ＴＭ４０１０、そしてＶｅｃｔｏｍｅｒ^ＴＭ４０２０と他の製造業者から初版されているその同等品））と、それらの混合物を含んでいる。１つ、あるいは複数のビニル・エーテル樹脂及び／又は１つ以上のエポキシ樹脂を（いずれの割合ででも）混合したものも利用することができる。多水酸機能性物質（例えば、米国特許第５，８５６，３７３号（Ｋａｉｓａｋｉ等））もエポキシ及び／又はビニル・エーテル機能性物質と組み合わせて用いることができる。
【００６９】
非硬化種としては、例えば、その可溶性が酸又はラジカル誘発反応によって増大される反応性ポリマーなどがある。こうした反応性ポリマーには、例えば、光発生酸によて水溶性酸基に転換することができるエステル基を含んだ水不溶性ポリマー（例えば、ポリ（ｔｅｒｔ−ブトキシカルボニルオキシスチレン）がある。非硬化樹脂にはＲ．Ｄ．Ａｌｌｅｎ，Ｇ．Ｍ，Ｗａｌｒａｆｆ，Ｗ．Ｄ，Ｈｉｎｓｂｅｒｇ，ａｎｄ　Ｌ．Ｌ．Ｓｉｍｐｔｏｎによって‘‘Ｈｉｇｈ　Ｐｅｒｆｏｒｍａｎｃｅｓ　Ａｃｒｙｌｉｃ　Ｐｏｌｙｍｅｒｓ　ｆｏｒ　Ｃｈｅｍｉｃａｌｌｙ　Ａｍｐｌｉｆｉｅｄ　Ｐｈｏｔｏｒｅｓｉｓｔ　Ａｐｐｌｉｃａｔｉｏｎｓ’’Ｊ．Ｖａｃ．Ｓｃｉ．Ｔｅｃｈｎｏｌ．Ｂ，９，３３５７（１９９１）に述べられているような化学的に増幅されるフォトレジストがある。これら化学的に増幅されるフォトレジストというコンセプトは現在ではマイクロチップ製造業界ではひろく行き渡っており、特に０．５ミクロン（あるいはさらに０．２ミクロン）以下の特性が知られている。こうしたフォトレジストでは、触媒性の種（通常水素イオン）を光照射によって発生させることができ、これには一連の化学反応が関与している。こうした一連の化学反応は水素がより多数の水素イオンや他の酸性種を発生させて、それによって反応速度を増大させるような反応を開始した場合に起きる。典型的な酸触媒化学増幅フォトレジスト・システムの例にはデプロテクション（例えば、米国特許第４，４９１，６２８号に述べられているようなｔ−ブトキシカルボニロキシスチレン・レジスト、米国特許第３，７７９，７７８号に述べられているようなトトラハイドロピラン（ＴＨＰ）メタクリレート系物質、ＴＨＰ−フェノール性物質、そしてＰ．Ｄ．Ａｌｌｅｎ等によってＰｒｏｃ．ＳＰＩＥ，２４３８，４７４（１９９５）に述べられているようなｔ−ブチル・メタクリレート系物質など）；脱重合化（例えば、ポリフタルアルデヒド系物質）；そして再構成（例えば、ピナコール再構成に基づく物質）などがある。
【００７０】
有益な非硬化性種としては、ロイコ染料などもあり、これは多光子光増感剤系によって発生される酸によって酸化されるまでは無色のままであり、酸化されると目に見えるような色を示す傾向がある。（酸化された染料は電磁スペクトルの可視部分（約４００〜７００ｎｍ）の光が吸収されるので発色する）。本発明において有益なロイコ染料は通常の酸化条件下で反応性を示し、酸化可能であるが、通常の環境条件の下ではそれほど反応性を示さず、酸化しないようなものである。そうした化学的タイプのロイコ染料は画像形成関係の化学者に多数知られている。
【００７１】
本発明で有用なロイコ染料にはアクリレート化ロイコ・アジン、フェノキサジン、フェノチアジンなどがあり、これらは、部分的に
【化２】

の式で示すことができ、この式で、Ｘは、Ｏ、Ｓ、及び−Ｎ−Ｒ^１１からなる群から選択され、Ｓが好ましく、Ｒ^１とＲ^２はそれぞれＨと炭素原子が１−約４個程度のアルキル基から選択され、Ｒ^３，Ｒ^４，Ｒ^６及びＲ^７はそれぞれ独立してＨおよび炭素原子が１〜約４のアルキル基、好ましくはメチルであり；Ｒ^５は炭素原子が１−約１６のアルキル基、炭素原子が１−約１６個のアルコキシ基、そして炭素原子が最大１６個までのアリル基であり；Ｒ^８は−Ｎ（Ｒ^１）（Ｒ^２）、Ｈ、炭素原子が１〜約４のアルキル基（Ｒ^１とＲ^２は上に述べたように選択、定義されるものとする）；Ｒ^９とＲ^１０はＨと炭素原子数が１〜約４のアルキル基からそれぞれ選択され；そして、Ｒ^１１は炭素原子数が１〜約４のアルキル基と炭素原子数が最大１１個までのアリル基から選択される（好ましくはフェニル基）。以下の化合物はこのタイプのロイコ染料の例である。
【化３】

【００７２】
他の有用なロイコ染料には、Ｌｅｕｃｏ　Ｃｒｙｓｔａｌ　Ｖｉｏｌｅｔ（４，４’，４’’−メチリジネトリス−（Ｎ，Ｎ−ジメシルアニリン）、Ｌｅｕｃｏ　Ｍａｌａｃｈｉｔｅ　Ｇｒｅｅｎ（ｐ，ｐ’−ベンジルイデネビス−（Ｎ，Ｎ−ジメチルジアミン））、以下の構造を有するＬｅｕｃｏ　Ａｔａｃｒｙｌ　Ｏｒａｎｇｅ−ＬＧＭ（色インデックスＢａｓｉｃ　Ｏｒａｎｇｅ　２１，Ｃｏｍｐ．Ｎｏ．４８０３５（フィッシャー塩基タイプ化合物））、
【化４】

以下の構造を有するＬｅｕｃｏ　Ａｔａｃｒｙｌ　Ｂｒｉｌｌａｎｔ　Ｒｅｄ−４Ｇ（Ｃｏｌｏｒ　Ｉｎｄｅｘ　Ｂａｓｉｃ　Ｒｅｄ　１４）
【化５】

以下の構造を有するＬｅｕｃｏ　Ａｔａｃｒｙｌ　Ｙｅｌｌｏｗ−Ｒ（Ｃｏｌｏｒ　Ｉｎｄｅｘ　Ｂａｓｉｃ　Ｙｅｌｌｏｗ　１１，Ｃｏｍｐ．Ｎｏ．４８０５５）
【化６】

Ｌｅｕｃ　Ｅｔｈｙｌ　Ｖｉｏｌｅｔ（４，４’，４’’−メチルイジネトリス−（Ｎ，Ｎ−ジエチルアニリン）、Ｌｅｕｃｏ　Ｖｉｃｔｏｒｉａ　Ｂｌｕｅ−ＢＧＯ（Ｃｏｌｏｒ　Ｉｎｄｅｘ　Ｂａｓｉｃ　Ｂｌｕｅ７２８ａ，Ｃｏｍｐ．　Ｎｏ．４４０４０；４，４’−メチルイジネビス−（Ｎ，Ｎ−ジエチルアニリン）−４−（Ｎ−エチル−１−ナフタルアミン）、及びＬｅｕｃｏ　Ａｔｌａｎｔｉｃ　Ｆｕｃｈｓｉｍｅ　Ｃｒｕｄｅ（４，４’，４’’−メチルイジネトリス−アニリン）がある。
【００７３】
ロイコ染料は通常は光感作層の総重量に対して重量で少なくとも約０．０１重量％（好ましくは、少なくとも約０，３重量％、より好ましくは少なくとも約１重量％、そして最も好ましくは、少なくとも約２〜１０重量％）のレベルで存在していてよい。結合剤、安定剤、表面活性剤、静電気防止剤、コーティング剤、潤滑剤、充填剤なども前記光感作層に存在していてもよい。当業者であれば添加剤の望ましい量は容易に分かるであろう。例えば、充填剤の量は書き込み波長に望ましくない散乱が起きないように選択される。
【００７４】
望ましいのであれば、異なったタイプの反応種の混合物を光反応性組成物で用いることもできる。例えば、遊離ラジカル−反応種と陽イオン反応種の混合物、硬化可能種と非硬化種の混合物なども有益である。
【００７５】
光反応開始剤系
（１）多光子光増感剤
光反応性組成物の多光子光反応開始剤系での使用に適した多光子光増感剤は十分な光に露光された場合に少なくとも２つの光子を同時に吸収することができるものである。好ましくは、それらはフルオレセインのものより大きな２光子吸収断面（つまり、３’，６’−ジヒドロキシスピロ［イソベンゼンフラン−１（３Ｈ），９’−［９Ｈ］キサンテン］３−ｏｎｅのそれより大きな吸収断面）を有している。一般的に、この断面はＣ．Ｘｕ及びＷ．Ｗ．Ｗｅｂｂ　ｉｎ　Ｊ．Ｏｐｔ．Ｓｏｃ．Ａｍ．Ｂ，１３，４８１（１９９６）（これは国際公報第ＷＯ９８／２１５２１号の８５頁、１８〜２２行によってＭａｒｄｅｒ　ａｎｄ　Ｐｅｒｒｙ等によっても引用されている）に述べられている方法で測定した場合、約５０×１０^−５０ｃｍ^４秒／光子以上であってもよい。
【００７６】
この方法はその光増感剤の２光子フルオレセイン強度の基準化合物の強度との（同じ励起強度及び光反応開始剤濃度条件下での）比較ステップを含んでいる。基準化合物は光反応開始剤吸収及び蛍光によってカバーされるスペクトル範囲にできるだけ適合するように選択することができる。１つの可能な実験的設定において、励起ビームを励起強度の５０％が光増感剤に入り、残りの５０％が基準物質に入るように２つのアームに分割することができる。そして前記光増感剤の基準化合物に対する相対蛍光強度は、２つの光倍増管チューブあるいはその他の較正済み検出装置で測定することができる。最後に、両方の化合物の蛍光量子効率を１光子励起状況で測定することができる。
【００７７】
蛍光及び燐光量子イールドを判定するための方法はこの技術分野ではよく知られている。一般的には問題の化合物の蛍光（あるいは燐光）スペクトル下の領域を周知の蛍光（あるいは燐光）量子イールドを有する標準的発光化合物の蛍光（または燐光）スペクトル下で比較し、そして、（例えば、励起波長でのその組成物の最適密度、蛍光検出装置の形状、放射波長の差、そして前記検出装置の異なった波長への応答を考慮に入れた）適切な訂正が行われる。標準的な方法は、例えば、Ｈａｎｄｂｏｏｋ　ｏｆ　Ｆｌｕｏｒｅｓｃｅｎｃｅ　Ｓｐｅｃｔｒａ　ｏｆ　Ａｒｏｍａｔｉｃ　Ｍｏｌｅｃｕｌｅｓ，　Ｓｅｃｏｎｄ　Ｅｄｉｔｉｏｎ，ｐａｇｅ２４〜２７，Ａｃａｄｅｍｉｃ　Ｐｒｅｓｓ，Ｎｅｗ　Ｙｏｒｋ（１９７１）の中でＩ．Ｂ．Ｂｅｒｌｍａｎによって、Ｊ．Ｐｈｙｓ．Ｃｈｅｍ．，７５，９９１〜１０２４（１９７１）でＪ．Ｎ．Ｄｅｍａｓ　ａｎｄ　Ｇ．Ａ．Ｃｒｏｓｂｙによって；そしてＪ．Ｐｈｙｓ．Ｃｈｅｍ．，８０，９６９〜９７４（１９７６）おいてＪ．Ｖ．Ｍｏｒｒｉｓ，Ｍ．Ａ，Ｍａｈｏｎｅｙによって、述べられている。
【００７８】
放射状態が１又は２光子励起の下で同じであると仮定して（共通の仮定）、光増感剤の２光子断面（δ_ｓａｍ）はδ_ｒｅｆＫ（Ｉ_ｓａｍ／Ｉ_ｒｅｆ）（φ_ｓａｍ／φ_ｒｅｆ）と等しく、ここでδ_ｒｅｆは基準化合物の２光子吸収断面であり、Ｉ_ｓａｍは光増感剤の蛍光強度であり、Ｉ_ｒｅｆは基準化合物の蛍光強度であり、φ_ｓａｍは光増感剤の蛍光量子効率であり、φ_ｒｅｆは基準物質の蛍光量子効率であり、そしてＫは光経路と２つの検出装置の応答のわずかな違いに対応するための補正係数である。Ｋはサンプル及び基準アームの両方で同じ光増感剤に対する応答を測定することで判定できる。有効な測定を行うためには、励起力に対する２光子蛍光強度の明らかな二次関数的依存を確認することができ、光増感剤と基準化合物の両方の比較的低い濃度を（蛍光再吸収し光増感剤凝集効果を避けるために）用いることができる。
【００７９】
その光増感剤が蛍光性にものでなければ、電子的励起状態のイールドを測定して周知の標準と比較することができる。蛍光イールドを判定する上に述べた方法に加えて、励起状態イールドを測定する種々の方法が知られている（例えば、一過性吸収、燐光イールド、光化学反応物生成あるいは光増感剤の（光反応からの）消失など）。
【００８０】
好ましくは、光増感剤の２光子吸収断面はフルオレシンの約１．５倍以上（言い換えると、前記の方法で測定して約７５×１０^−５０ｃｍ^４秒／光子以上）、そしてより好ましくはフルオレシンの約２倍以上（言い換えると、前記の方法で測定して約１００×１０^−５０ｃｍ^４秒／光子以上）、最も好ましくはフルオレシンの約３倍以上（言い換えると、前記の方法で測定して約１５０×１０^−５０ｃｍ^４秒／光子以上）、任意には、フルオレシンの約４倍以上（言い換えると、前記の方法で測定して約２００×１０^−５０ｃｍ^４秒／光子以上）である。
【００８１】
好ましくは、前記光増感剤は反応種に（その反応種が液体であれば）可溶性であり、反応種およびその組成物に含まれているいずれの（以下に述べるような）結合剤とも共存可能である。最も好ましくは、この光増感剤は米国特許第３，７２９，３１３号で述べられているテスト手順を用いて、その非ハブの単一光子吸収スペクトルに重なり合う波長範囲（単一光子吸収条件）で連続的に照射することで２−メチル−４，６−ｂｉｓ（トリクロロメチル）−ｓ−トリアジンを感光性にすることができる。現在利用できる素材を用いて、このテストは以下のように実行することができる。
【００８２】
以下の組成：つまり、（単位体積あたり）５（重量）％溶液を４５，０００〜５５，０００分子重量のメタノールに溶かしたもの５．０部、９．０〜１３．０％ヒドロキシル含有ポリビニル・ブチラル（Ｂｕｔｖａｒ^ＴＭＢ７６、Ｍｏｎｓａｎｔｏ）、０．３部のトリメチロルプロパン；及び０．０３部の２−メチル−４，６−ｂｉｓ（トリクロロメチル）−ｓ−トリアジン（Ｂｕｌｌ．Ｃｈｅｍ．Ｓｏｃ．Ｊａｐａｎ，４２，２９２４〜２９３０（１９６９）参照）の組成を有する標準テスト溶液を調製する。この溶液に、０．０１部のテストされる化合物を光増感剤として加える。得られた溶液を０．０５ｍｍのナイフ・オリフィスを用いて０．０５ｍｍの清潔なポリエステル・フィルム上にナイフ・コーティングし、その被膜を３０分間程度空気乾燥する。０．０５ｍｍの透明なポリエステル・カバー・フィルムを乾燥しているが柔からで粘着性の被覆上にできるだけ空気を閉じ込めないように注意しながら被せる。得られたサンドイッチ構造を可視光線と紫外線の両方の領域で光を提供するタングステン光源（ＦＣＨＴＭ　６５０ワット・クオーツ・ヨード・ランプ、Ｇｅｎｅｒａｌ　Ｅｌｅｃｔｒｉｃ）からの光に１６１，０００Ｌｕｘの入射光に３分間露光させる。露光はステンシルを介して行い、前記構造に露光された領域と露光されない領域を作り出すことができる。露光語、フィルムを取り外し、そして被覆を通常静電写真法で使われるようなカラー・トナー粉末などの細かに分割された色付き粉末で処理する。テストされる物質が光増感剤であれば、トリメチロルプロパン・トリメタクリレート・モノマーが２−メチル−４，６−ｂｉｓ（トリクロロメチル）−ｓ−トリアジンからの光発生遊離ラジカルによって露光領域内でポリマー化される。ポリマー化された領域は基本的にはねばつきがなく、色付き粉末は選択的に、基本的にはその被覆のねばついた非露光領域だけに接着して、その型板に対応した目で見える画像を形成する。
【００８３】
好ましくは、光増感剤は一部には保存安定性を考慮に入れて選択することもできる。従って、特定の光増感剤の選択はある程度用いられる特定の反応種（及び電子供与体化合物及び／又は光反応開始剤の選択）にかかっている。
【００８４】
特に好ましい多光子光増感剤には、Ｒｈｏｄａｍｉｎｅ　Ｂ（つまり、Ｎ−［９−（２−カルボキシフェニル）−６−（ジチルアミノ）−３Ｈ−キサンタン−３−イリデン］−Ｎ−エチルエタンアミニウム・クロライド、及びＲｈｏｒｄａｍｉｎｅＢのヘキサフルオロアツモネート塩）及び、例えば、国際特許公報ＷＯ９８／２１５２１及びＷＯ９９／５３２４２でＭａｒｄｅｒとＰｅｒｒｙ等によって開示されているような４つの種類の光増感剤など、大きな多光子吸収断面を示すものなどである。これら４つの種類は以下の通りである。（ａ）２つのドナーが接合π（ｐｉ）電子ブリッジに接続されている分子、（ｂ）２つのドナーが１つ以上の電子受容基によって置換されている接合π（ｐｉ）電子ブリッジに接続されている分子、（ｃ）２つの受容体が接合π（ｐｉ）電子ブリッジに接続されている分子、そして（ｄ）２つの受容体が１つ以上の電子受容基によって置換されている接合π（ｐｉ）電子ブリッジに接続されている分子。（ここで、『ブリッジ』とは２つ以上の化学基を接続する分子フラグメント、『ドナー』は接合π（ｐｉ）電子ブリッジｎ結合することができる低イオン化ポテンシャルを有する原始あるいは基を、そして『受容体』とは接合π（ｐｉ）電子ブリッジに結合することができる高電子親和性を有する原子または基をそれぞれ意味している）。
【００８５】
かかる光増感剤の代表的な例として下記式が挙げられる。
【化７】

【化８】

【化９】

【化１０】

【化１１】

【００８６】
上に述べた４つのタイプの光増感剤は標準的なＷｉｔｔｉｇ条件下でアルデヒドをイリドに反応させるか、あるいは国際特許Ｎｏ．ＷＯ９８／２１５２１に詳述されているようにＭｃＭｕｒｒａｙ反応を用いて調製することができる。
【００８７】
他の化合物はＲｅｉｎｈａｒｄｔ等によって（例えば、国際特許第６，１００，４０５、５，８５９，２５１及び５，７７０，７３７で）大きな多光子吸収断面を有するものと述べられているが、これらの断面は上に述べたのとは別の方法で測定されたものである。相した化合物の代表的な例は以下の通りである。
【化１２】

【化１３】

【００８８】
本発明において光増感剤として利用できる可能性がある他の化合物は、フルオレシン、ｐ−ｂｉｓ（ｏ−メチルスチリル）ベンゼン、エオシン、ローズ・ベンガル、エリスロシン、クマリン３０７（Ｅａｓｔｍａｎ　Ｋｏｄａｋ）、Ｃａｓｃａｄｅ　Ｂｌｕｅ　ヒドラジン塩、Ｌｕｃｃｉｆｅｒ　Ｙｅｌｌｏｗ　ＣＨアンモニウム塩、４，４−ジフルオロ−１，３，５，７，８−ペンタメチル−４−ボラ−３α、４α−ジアザインデセン−２，６−ジスルホン酸塩、１，１−ジオクタルデシル−３，３，３’，３’−テトラメチルインドカルボシアニン、インド−１ペンタカリウム塩（Ｍｏｌｅｃｕｌａｒ　Ｐｒｏｂｅｓ）、５−ジエチルアミノナフタレン−１−スルホニル・ヒドラジン、４’，６−ジアミジノ−２−フェニルインドル・ジヒドロクロライド、５，７−ジヨード−３−ブトキシ−６−フルオロン、９−フルオロン−２−カルボン酸、そして以下の構造を有する化合物である。
【化１４】

【化１５】

【００８９】
（２）電子供与体化合物
光反応性組成物の多光子光反応開始剤系内で有用な電子供与体化合物は（その光増感剤自体を除いて）前記光増感剤の電子励起状態に電子を提供できる化合物である。これらの電子供与体化合物は好ましくはゼロよりか大きく、標準飽和カロメル電極に対するｐ−ジメトキシベンゼンのそれ以下である酸化ポテンシャルを有している。好ましくは、酸化ポテンシャルは標準飽和カロメル電極（Ｓ．Ｃ．Ｅ）を基準として約０．３〜１ボルトの間である。
【００９０】
電子供与体化合物はさらに反応種内に可溶性であることが好ましく、一部には（上に述べたような）保存安定性を考慮に入れて選択される。適切なドナーは通常望ましい波長の光に露光されると、（硬化などの）反応速度あるいは画像密度を増大させることができる。
【００９１】
陽イオン反応種を用いて作業する場合、当業者は、電子供与体化合物は、実質的に塩基性を有している場合は陽イオン性反応に対して悪影響を及ぼす場合があることを認識するであろう。（例えば、米国特許第６，０２５，４０６号（Ｏｘｍａｎ等）、欄７、行６２から欄８、行４９参照）。
【００９２】
一般的に、特定の光増感剤及び光反応開始剤と共に使用するのに適した電子供与体化合物は（例えば、米国特許第４，８５９，５７２号（Ｆａｒｉｄ等）に述べられているように）それら３つの構成部分の酸化還元ポテンシャルを比較することで選択される。こうしたポテンシャルは（例えば、Ｒ．Ｊ．Ｃｏｘ，Ｐｈｏｔｏｇｒａｐｈｉｃ　Ｓｅｎｓｉｔｉｖｉｔｙ，Ｃｈａｐｔｅｒ１５，Ａｃａｄｅｍｉｃ　Ｐｒｅｓｓ（１９７３）に述べられている方法で）実験的に測定することができ、あるいはＮ．Ｌ．Ｗｅｉｎｂｕｒｇ，Ｅｄ．，Ｔｅｃｈｎｉｑｕｅ　ｏｆ　Ｅｌｅｃｔｒｏｏｒｇａｎｉｃ　Ｓｙｎｔｈｅｓｉｓ　ｐａｒｔ　ＩＩ　Ｔｅｃｈｎｉｑｕｅｓ　ｏｆ　Ｃｈｅｍｉｓｔｒｙ，Ｖｏｌ．Ｖ（１９７５）、及びＣ．Ｋ，Ｍａｎｎ　ａｎｄ　Ｋ．Ｋ．Ｂａｒｎｅｓ，Ｅｌｅｃｔｒｏｎｃｈｅｍｉｃａｌ　ｒｅａｃｔｉｏｎｓ　ｉｎ　Ｎｏａｑｕｅｏｕｓ　Ｓｙｓｔｅｍｓ（１９７０）などの参考文献にも示されている。このポテンシャルは相対的エネルギー関係を反映しており、そして以下の方法で電子供与体化合物選択に適用することができる。
【００９３】
光増感剤が電子的励起状態にある場合、その光増感剤の最高占有分子軌道（ＨＯＭＯ）はより高いエネルギー・レベル（つまり、その光増感剤の最低非占有分子軌道（ＬＵＭＯ））に上昇しており、それが最初に占有していた分子軌道内に空隙が残されている。光反応開始剤はより高いエネルギー軌道から電子を受け取り、そして、特定の相対的エネルギー関係が満たされると、その電子供与体化合物は電子を提供して最初の占有軌道の空隙を満たす。
【００９４】
その光反応開始剤の還元ポテンシャルが光増感剤と比較してよりネガティブ（あるいはよりポジティブ）である場合、これは発熱プロセスであるから、その光増感剤のより高いエネルギー軌道内の電子はその光増感剤からその光反応開始剤の最低非占有分子軌道（ＬＵＭＯ）に移る。そのプロセスが多少球熱性であれば（つまり、その光増感剤の還元ポテンシャルが光反応開始剤のそれと比較して最大０．１ボルトよりネガティブであっても）、周辺の熱活性がそうした小さなバリアを易々と乗り越えてしまう。
【００９５】
同様の方法で、電子供与体化合物の酸化ポテンシャルが光反応開始剤のそれと比較してポジティブではない場合（あるいはよりネガティブであれば）、土でかのＨＯＭＯから光増感剤の軌道空隙に移動する電子はより高い電位からより低い電位に移動しているのであって、これも発熱性プロセスを示している。このプロセスが多少吸熱性であっても（つまり、その光増感剤の酸化ポテンシャルが電子供与体化合物のそれより最大０．１ボルトよりポジティブであっても）、周辺熱活性化がそうした小さなバリアを容易に克服してしまう。
【００９６】
光増感剤の還元ポテンシャルが光反応開始剤のそれと比較して最大０．１ボルトよりネガティブであれば、あるいは光増感剤の酸化ポテンシャルがその電子供与体化合物のそれと比較して最大０．１ボルトよりポジティブである軽度の吸熱性反応は、光反応開始剤と電子供与体化合物のどちらが最初にその励起状態にある光増感剤と反応するかには関係なく、どの瞬間にでも起きる。光反応開始剤あるいは電子供与体化合物がその励起状態にある光増感剤と反応している場合、その反応は発熱性であるか、多少の吸熱性であることが好ましい。光反応開始剤か電子供与体化合物が光増感剤イオン・ラジカルと反応している場合も発熱性反応が望ましいが、それでもより吸熱性の反応が多くの瞬間に起きることが予想される。従って、光反応開始剤の還元ポテンシャルは二番目に反応する光反応開始剤のそれと比較して最大０．２ボルト（あるいはそれ以上）よりネガティブであってよいし、あるいは光増感剤の酸化ポテンシャルが二番目に反応する電子供与体化合物のそれと比較して最大０．２ボルト（あるいはそれ以上）ポジティブであってもよい。
【００９７】
適切な電子供与体化合物には、例えば、Ｄ．Ｆ．ＦａｔｏｎがＡｄｖａｎｃｅｓ　ｉｎ　Ｐｈｏｔｏｃｈｅｍｉｓｔｏｒｙ，ｅｄｉｔｅｄ　ｂｙ　Ｂ．Ｖｏｍａｎ　ｅｔ　ａｌ．，Ｖｏｌｕｍｅ１３，ｐｐ．４２７〜４８８，Ｊｏｈｎ　Ｗｉｌｅｙ　ａｎｄ　Ｓｏｎｓ，Ｎｅｗ　Ｙｏｒｋ（１９８６）で、あるいはＯｘｍａｎｎ等が米国特許第６，０２５，４０６号の欄７、行４２〜６１で、そしてＰａｌａｚｚｏｔｔｏ等が米国特許第５，５４５，６７６号の欄４、行１４から欄５、行１８に述べているようなものがある。そうした電子供与体化合物は（トリエタノールアミン、ヒドラジン、１，４−ジアザビシクロ［２，２，２］オクタン、トリフェノールアミン（及びそのトリフェニルホスフィン及びトリフェニルアルシン類似物など、アミノアルデヒド、そしてアミノシランなどを含む）アミン類、（ホスホルアミドを含む）アミド類、（チオエーテルを含む）エーテル類、硫酸及びその塩、フェノシアニドの塩、アスコルピン酸とその塩、キサンタンの塩、エチレン・ジアミン・四酢酸、（アルキル）ｎ（アリル）ｎホウ酸塩（ｎ＋ｍ＝４）（好ましくはテトラアルキスアンモニウム塩）、ＳｎＲ４化合物（各Ｒはアルキル、アラルキル（特にベンジル）、アリル、そしてアルカリル基からなる群からそれぞれ選択される）種々の有機金属化合物（例えば、ｎ−Ｃ_３Ｈ_７Ｓｎ（ＣＨ_３）_３、（アリル）Ｓｎ（ＣＨ_３）_３、及び（ベンジル）Ｓｎ（ｎ−Ｃ_３Ｈ_７）_３などの化合物）、フェロシンなど、及びそれらの混合物である。電子供与体化合物は未置換でもよいし、１つ以上の非干渉性置換基で置換されていてもよい。特に好ましい電子供与体化合物は（窒素、酸素、リン、及び硫黄原子などの）電子ドナー原子とその電子ドナー原子に加えて炭素又はケイ素原子に結合した抽出可能な水素原子を含んでいる。
【００９８】
好ましいアミン系電子供与体化合物にはアルキル−、アリル−、アルカリル−、及びアラルキル−アミン（例えば、メチルアミン、エチルアミン、プロピルアミン、ブチルアミン、トリエタノールアミン、アミルアミン、２，４−ジメチルアニリン、２，３−ジメチルアニリン、ｏ−、ｍ−、及びｐ−トルイジン、ベンジルアミン、アミノピリジン、Ｎ，Ｎ’−ジメチルエチレンジアミン、Ｎ，Ｎ’−ジエチルエチルジアミン、Ｎ，Ｎ’−ジベンジルエチレンジアミン、Ｎ，Ｎ’−ジエチル−１，３−プロパンジアミン、Ｎ，Ｎ’−ジエチル−２−ブテン−１，４−ジアミン、Ｎ，Ｎ’−ジメチル−１，６−ヘキサンジアミン、ピペラジン、４，４’−トリメチレンジピペラジン、４，４’−エチレンジピペラジン、ｐ−Ｎ，Ｎ−ジメチル−アミノフェンタノル、及びｐ−Ｎ，Ｎ−ジメチルアミノベンゾニトリル）；アミノアルデヒド（例えば、ｐ−Ｎ，Ｎ−ジメチルアミノベンズアルデヒド、ｐ−Ｎ，Ｎ−ジエチルアミノベンズアルデヒド、９−ジュロリジン、及び４−モルフォインベンズアルデヒド）；そしてアミノシラン（例えば、トリエチルシリルモルフォリン、トリメチルシリルピペリジン、ｂｉｓ（ジメチルアミノ）ジフェニルシラン、ｔｒｉｓ（ジメチルアミノ）メチルシラン、Ｎ，Ｎ−ジエチルアミノトリメチルシラン、ｔｒｉｓ（ジメチルアミノ）フェニルシラン、ｔｒｉｓ（メチルシリル）アミン、ｂｉｓ（ジメチルシリル）アミン、Ｎ，Ｎ−ｂｉｓ（ジメチルシリル）アニリン、Ｎ−フェニル−Ｎ−ジメチルシリルアニリン、及びＮ，Ｎ−ジメチル−Ｎ−ジメチルシリルアミン）；及びそれらの混合物である。三級芳香性アルキルアミン、特に少なくとも１つの電子引き出し基を芳香管上に有しているものが特に優れた保存安定性を有していることが分かっている。優れた保存安定性は室温で個体であるアミンを用いても得ることができる。優れた写真速度は１つ以上のジュロジニル構成部分を含むアミンを用いて得られた。
【００９９】
好ましいアミン系電子供与体化合物にはＮ，Ｎ−ジメチルアセトアミン、Ｎ，Ｎ−ジエチルアセトアミン、Ｎ−メチル−Ｎ−フェニルアセトアミン、ヘキサメチルホスホルアミン、ヘキサエチルホスホルアミン、ヘキサプロピルホスホルアミン、酸化トリモルホリンホスフィン、酸化トリピペラジノホスフィン、及びそれらの混合物である。
【０１００】
好ましいアルキルアリルボレート塩には以下のものがある。
Ａｒ_３Ｂ⁻（ｎ−Ｃ_４Ｈ_９）Ｎ^＋（Ｃ_２Ｈ_５）_４
Ａｒ_３Ｂ⁻（ｎ−Ｃ_４Ｈ_９）Ｎ^＋（ＣＨ_３）_４
Ａｒ_３Ｂ⁻（ｎ−Ｃ_４Ｈ_９）Ｎ^＋（ｎ−Ｃ_４Ｈ_９）_４
Ａｒ_３Ｂ⁻（ｎ−Ｃ_４Ｈ_９）Ｌｉ^＋
Ａｒ_３Ｂ⁻（ｎ−Ｃ_４Ｈ_９）Ｎ^＋（Ｃ_６Ｈ_１３）_４
Ａｒ_３Ｂ⁻（Ｃ_４Ｈ_９）Ｎ^＋（ＣＨ_３）_３（ＣＨ_２）_２ＣＯ_２（ＣＨ_２）ＣＨ_３Ａｒ_３Ｂ⁻（Ｃ_４Ｈ_９）Ｎ^＋（ＣＨ_３）_３（ＣＨ_２）_２ＯＣＯ（ＣＨ_２）_２ＣＨ_３
Ａｒ_３Ｂ⁻（ｓｅｃ−Ｃ_４Ｈ_９）Ｎ^＋（ＣＨ_３）_３（ＣＨ_２）_２ＣＯ_２（ＣＨ_２）ＣＨ_３
Ａｒ_３Ｂ⁻（ｓｅｃ−Ｃ_４Ｈ_９）Ｎ^＋（Ｃ_６Ｈ_１３）_４
Ａｒ_３Ｂ⁻（Ｃ_４Ｈ_９）Ｎ^＋（Ｃ_８Ｈ_１７）_４
Ａｒ_３Ｂ⁻（Ｃ_４Ｈ_９）Ｎ^＋（ＣＨ_３）_４
（ｐ−ＣＨ_３Ｏ−Ｃ_６Ｈ_４）_３Ｂ⁻（ｎ−Ｃ_４Ｈ_９）Ｎ^＋（ｎ−Ｃ_４Ｈ_９）_４
Ａｒ_３Ｂ⁻（Ｃ_４Ｈ_９）Ｎ^＋（ＣＨ_３）_３（ＣＨ_２）_２ＯＨ
ＡｒＢ⁻（ｎ−Ｃ_４Ｈ_９）_３Ｎ^＋（ＣＨ_３）_４
ＡｒＢ⁻（Ｃ_２Ｈ_５）_３Ｎ^＋（ＣＨ_３）_４
Ａｒ_２Ｂ⁻（ｎ−Ｃ_４Ｈ_９）_２Ｎ^＋（ＣＨ_３）_４
Ａｒ_３Ｂ⁻（Ｃ_４Ｈ_９）Ｎ^＋（Ｃ_４Ｈ_９）_４
Ａｒ_４Ｂ⁻Ｎ^＋（Ｃ_４Ｈ_９）_４
ＡｒＢ⁻（ＣＨ_３）_３Ｎ^＋（ＣＨ_３）_４
（ｎ−Ｃ_４Ｈ_９）_４Ｂ⁻Ｎ^＋（ＣＨ_３）_４
Ａｒ_３Ｂ⁻（Ｃ_４Ｈ_９）Ｐ^＋（Ｃ_４Ｈ_９）_４
（ここで、Ａｒはフェニル、ナフチル、置換（好ましくはフルオロ置換）フェニル、置換ナフチル、及びより多くの融合芳香環を有する同様の基）、及びテトラメチルアンモニウムｎ−ブチルトリフェニルボレート及びテトラブチルアンモニウムｎ−ヘキシル−ｔｒｉｓ（３−フルオロフェニル）ボレート（Ｃｉｂａ　Ｓｐｅｃｉａｌｔｙ　Ｃｈｅｍｉｃａｌｓ　ＣｏｒｐｏｒａｔｉｏｎからＣＧＩ　４３７及びＣＧＩ　７４６として市販）、及びそれらの混合物である。
【０１０１】
適切なエーテル電子供与体化合物は４，４’−ジメトキシビフェニル、１，２，４−トリエトキシベンゼン、１，２，４，５−テトラメトキシベンゼンなど、及びそれらの混合物である。適切な尿素電子供与体化合物はＮ，Ｎ’−ジメチルウレア、Ｎ，Ｎ−ジメチルウレア、Ｎ，Ｎ’−ジフェニルウレア、テトラメチルチオウレア、テトラエチルチオウレア、テトラ−ｎ−ブチルチオウレア、Ｎ，Ｎ−ジ−ｎ−ブチルチオウレア、Ｎ，Ｎ’−ジ−ｎ−ブチルチオウレア、Ｎ，Ｎ−ジフェニルチオウレア、Ｎ，Ｎ’−ジフェニル−Ｎ，Ｎ’−ジエチルチオウレアなど、及びそれらの混合物である。
【０１０２】
遊離ラジカル誘発反応のための好ましい電子供与体化合物は１つ以上のジュロリジニル構成部分、アルキルボレート塩、及び芳香性硫酸塩を含むアミンなどである。しかしながら、そうした反応のためには、望ましければ（例えば、光反応性組成物の保存安定性を改善したり、あるいは解像度、コントラスト、そしてレシプロシティを修正するなど）、こうした電子供与体化合物を使用しなくてもよい場合もある。酸誘発反応のための好ましい電子供与体化合物には４−ジメチルアミノ安息香酸、エチル−４−ジメチルアミノベンゾエート、３−ジメチルアミノ安息香酸、４−ジメチルアミノベンゾイン、４−ジメチルアミノベンズアルデヒド、４−ジメチルアミノベンゾニトリル、４−ジメチルアミノフェネチル・アルコール、及び１，２，４−トリメトキシベンゼンなどである。
【０１０３】
（３）光反応開始剤
光反応性組成物の反応種の適切な光反応開始剤は電子励起状態にある他行し光増感剤からの電子を受け入れることで感光性にすることができ、少なくとも遊離ラジカル及び／又は酸の形成をもたらす。こうした光反応開始剤には、ヨードニウム塩（例えば、ジアリルヨードニウム塩）、クロロメチレート化トリアジン（例えば、２−メチル−４，６−ｂｉｓ（トリクロロメチル）−ｓ−トリアジン、２，４，６−ｔｒｉｓ（トリクロロメチル）−ｓ−トリアジン、及び２−アリル−４，６−ｂｉｓ（トリクロロメチル）−ｓ−トリアジン）、ジアゾニウム塩（例えば、任意にアルキル、アルコキシ、ハロ、又はニトロなどの基によって置換されたフェニルジアゾニウム塩）、スルホニウム塩（例えば、任意にアルキル又はアルコキシ基、そして任意に隣接アリル構成部分に架橋している２，２’−オキシ基トリアリルスルホニウム塩で置換されたトリアリルスルホニウム）、アジニウム塩（例えば、Ｎ−アルコキシピリジニウム）、そしてトリアリルイミダゾリル・ダイマー（好ましくは、任意にアルキル、アルコキシ、又はハロによって置換された２，２’，４，４’，５，５’−テトラフェニル−１’１’−ビイミダゾルなどの２，４，５−トリフェニルイミダゾイル・ダイマー）など、及びそれらの混合物である。
【０１０４】
光反応開始剤は好ましくは反応種に対して可溶性であり、好ましくは保存時の安定性も優れている（つまり、光増感剤と電子供与体化合物の存在下で溶解された場合に反応種の反応を自発的に促進しない）。従って、特定の光反応開始剤の選択はある程度その特定の反応種、光増感剤、及び上に述べたような電子供与体化合物に依存している。好ましい光反応開始剤はＰＣＴ特許出願ＷＯ９８／２１５２１及びＷＯ９９５／３２４２においてＭａｒｄｅｒ，Ｐｅｒｒｙ等によって、さらにＰＣＴ特許出願ＷＯ９９／５４７８４においてＧｏｏｄｍａｎ等によって述べられているような大きな多光子吸収断面を有しているものである。
【０１０５】
適切なヨードニウム塩には米国特許第５，５４５，６７６号の欄２、行２８〜４６でＰａｌａｚｚｏｔｏ等によって述べられているようなものがある。適切なヨードニウム塩は米国特許第３，７２９，３１３号、同第３，７４１，７６９号、同第３，８０８，００６号、同第４，２５０，０５３号及び同第４，３９４，４０３号に述べられている。ヨードニウム塩は単純な塩（例えば、Ｃｌ⁻、Ｂｒ⁻、Ｉ⁻、又はＣ_４Ｈ_５ＳＯ_３ ⁻）あるいは金属複合体塩（例えば、ＳｂＦ_６ ⁻、ＰＦ_６ ⁻、ＢＦ_４ ⁻、テトラキス（ペルフルオロフェニル）ボレート、ＳｂＦ_５ＯＨ⁻あるいはＡｓＦ_６ ⁻）である。ヨードニウム塩の混合物も必要があれば用いることができる。
【０１０６】
有益な芳香性ヨードニウム錯体塩光反応開始剤の例としては、ジフェニルヨードニウム・テトラフルオロボレート；ジ（４−メチルフェニル）ヨードニウム・テトラフルオロボレート；フェニル−４−メチルフェニルヨードニウム・トトラフルオロボレート；ジ（４−ヘプチルフェニル）ヨードニウム・テトラフルオロボレート；ジ（３−ニトロフェニル）ヨードニウム・ヘキサフルオロホスフェート；ジ（４−クロロフェニル）ヨードニウム・ヘキサフルオロホスフェート；ジ（ナフチル）ヨードニウム・テトラフルオロボレート、ジ（４−トリフルオロメチルフェニル）ヨードニウム・テトラフルオロボレート；ジフェニルヨードニウム・ヘキサフルオロホスフェート；ジ（４−メチルフェニル）ヨードニウム・ヘキサフルオロホスフェート；ジフェニルヨードニウム・ヘキサフルオロアルセネート；ジ（４−フェノキシフェニル）ヨードニウム・テトラフルオロボレート；フェニル−２−チオニルヨードニウム・ヘキサフルオロホスフェート；３，５−ジメチルピラゾリル−４−フェニルヨードニウム・ヘキサフルオロホスフェート；ジフェニルヨードニウム・ヘキサフルオロアンチモネート；２，２’−ジフェニルヨードニウム・テトラフルオロボレート；ジ（２，４−ジクロロフェニル）ヨニ・ヘキサフルオロホスフェート；ジ（４−ブロモフェニル）ヨードニウム・ヘキサフルオロホスフェート；ジ（４−メトキシフェニル）ヨニ・ヘキサフルオロホスフェート；ジ（３−カルボキシフェニル）ヨードニウム・ヘキサフルオロホスフェート；ジ（３−オキシカルボニルフェニル）ヨードニウム・ヘキサフルオロホスフェート；ジ（３−メトキシスルホニルフェニル）ヨードニウム・ヘキサフルオロホスフェート；ジ（４−アセトアミドフェニル）ヨードニウム・ヘキサフルオロホスフェート；ジ（２−ベンゾチエニル）ヨードニウム・ヘキサフルオロホスフェート；及びジフェニルヨードニウム・ヘキサフルオロアンチモネートなど、及びそれらの混合物である。芳香性ヨードニウム錯体塩はＢｅｒｉｎｇｅｒｅｔ．ａｌ．，Ｊ．Ａｍ．Ｃｈｅｍ．Ｓｏｃ．，８１，３４２（１９５９）に従って（例えば、ジフェニルヨードニウム・ビスルフェート）の転換によって調製することができる。
【０１０７】
好ましいヨードニウム塩はジフェニルヨードニウム（塩化ジフェニルヨードニウム、ジフェニルヨードニウム・ヘキサフルオロホスフェート、及びジフェニルヨードニウム・テトラフルオロボレート）、ジアリルヨードニウム・ヘキサフルオロホアンチモネート（例えば、Ｓａｒｔｏｍｅｔｅｒ　Ｃｏｍｐａｎｙから市販されているＳａｒＣａｔ^ＴＭＳＲ　１０１２）、及びそれらの混合物である。
【０１０８】
有益なジクロロメチル化トリアジンには米国特許第３，７７９，７７８号（Ｓｍｉｔｈ等）、欄８、行４５〜５０に述べられているものがあり、それには２，４−ｂｉｓ（トリクロロメチル）−６−メチル−ｓ−トリアジン、２，４，６−ｔｒｉｓ（トリクロロエチル）−ｓ−トリアジン、そして米国特許第３，９８７，０３７号及び同第３，９５４，４７５号（Ｂｏｎｈａｍ等）に開示されているより好ましいクロモルホア置換ビニルハロメチル−ｓ−トラジンなどである。
【０１０９】
有益なジアゾニウム塩には米国特許第４，３９４，４３３号（ｇａｔｚｋｅら）に述べられているものなどがあり、それには外部ジアゾニウム基（−Ｎ^＋＝Ｎ）及び陰イオンを有する感光芳香性構成部分を含んでいるもの（例えば、塩素、トリ−イソプロピル・ナフタレン・スルホネート、テトラフルオロボレート、及びｂｉｓ（ペルフルオロアルキルスルホニル）メチドなど）などである。有益なジアゾニウムの例には１−ジアゾ−４−アニリロベンゼン、Ｎ−（４−ジアゾ−２，４−ジメトキシフェニル）ピロリンジン、１−ジアゾ−２，４−ジエトキシ−４−モルホリノ・ベンゼン、１−ジアゾ−４−ベンゾイル・アミノ−２，５−ジエトキシ・ベンゼン、４−ジアゾ−２，５−ジブトキシ・フェニル・モルホリノ、４−ジアゾ−１−ジメチルアニリン、１−ジアゾ−Ｎ，Ｎ−ジメチルアニリン、１−ジアゾ−４−Ｎ−メチル−Ｎ−ヒドロキシエチル・アニリンなどである。
【０１１０】
有効なスルホニウム塩は米国特許第４，２５０，０５３号（Ｓｍｉｔｈ）、欄１、行６６から欄４、行２に述べられており、以下の式：
【化１６】

で示されるもの、Ｒ_１、Ｒ_２、及びＲ_３はそれぞれ炭素原子数が約４〜約２０炭素原子の芳香基（例えば、置換あるいは未置換フェニル、ナフチル、チエニル、及びフラニルなどで、置換基はアルコキシ、アルキルチオ、アリルチオ、ハロゲンなどである）及び炭素原子数が１から約２０のアルキル基からなる群から選択されるものである。ここで述べられている『アルキル』とは置換アルキル（例えば、ハロゲン、アルコキシ、又はアリルで置換されたもの）などである。Ｒ_１、Ｒ_２、及びＲ_３の少なくとも１つは芳香性であり、そして、好ましくはそれぞれが独立して芳香性である。Ｚは共有結合、酸素、硫黄、−Ｓ（＝Ｏ）−、−Ｃ（＝Ｏ）−、−（Ｏ＝）Ｓ（＝Ｏ）−、及び−Ｎ（Ｒ）−であり、Ｒは（フェニルなど炭素数が約６〜２０の）アリル、（アセチル、ベンゾイルなど炭素数が約２〜約２０の）アリル、炭素−炭素結合、あるいは−（Ｒ_４−）Ｃ（−Ｒ_５）−であり、Ｒ_４とＲ_５は水素、炭素数が１〜約４のアルキル基、炭素数が約２〜約４のアルケニル基からなる群からそれぞれ選択され、Ｘ⁻は以下に述べると通りである。
【０１１１】
スルホニウム（及びその他のタイプの光反応開始剤）のための適切な陰イオン、Ｘ⁻には、例えば、イミド、メチド、ボロン、燐、アンチモン、砒素、及びアルミニウムを中心とする陽イオンなど種々の陰イオンが含まれる。
【０１１２】
適切なイミド及びメチド陰イオンは（Ｃ_２Ｆ_５ＳＯ_２）_２Ｎ⁻、（Ｃ_４Ｆ_９ＳＯ_２）_２Ｎ⁻、（Ｃ_８Ｆ_１７ＳＯ_２）_３Ｃ⁻、（ＣＦ_３ＳＯ_２）_３Ｃ⁻、（ＣＦ_３ＳＯ_２）_２Ｎ⁻、（Ｃ_４Ｆ_９ＳＯ_２）_３Ｃ⁻、（ＣＦ_３ＳＯ_２）_２（Ｃ_４Ｆ_９ＳＯ_２）Ｃ⁻、（ＣＦ_３ＳＯ_２）（Ｃ_４Ｆ_９ＳＯ_２）_２Ｎ⁻、（（ＣＦ_３）_２ＮＣ_２Ｆ_４ＳＯ_２）_２Ｎ⁻、（ＣＦ_３）_２ＮＣ_２Ｆ_４ＳＯ_２Ｃ⁻（ＳＯ_２ＣＦ_３）_２、（３，５−ｂｉｓ（ＣＦ_３）Ｃ_６Ｈ_３）ＳＯ_２Ｎ⁻ＳＯ_２ＣＦ_３、Ｃ_６Ｈ_５ＳＯ_２Ｃ⁻（ＳＯ_２ＣＦ_３）_２，Ｃ_６Ｈ_５ＳＯ_２Ｎ⁻ＳＯ_２ＣＦ_３などである。このタイプの陰には（Ｒ_ｆＳＯ_２）_３Ｃ−で示されるものがあり、ここでＲ_ｆは炭素原子数が１〜約４のペルフルオロアルキル・ラジカルである。
【０１１３】
適切なボロン中心陰イオンとしては、Ｆ_４Ｂ−、（３，５−ｂｉｓ（ＣＦ_３）Ｃ_６Ｈ_３）_４Ｂ⁻、（Ｃ_６Ｆ_５）_４Ｂ⁻、（ｐ−ＣＦ_３Ｃ_６Ｈ_４）_４Ｂ⁻、（ｍ−ＣＦ_３Ｃ_６Ｈ_４）_４Ｂ⁻、（ｐ−ＦＣ_６Ｈ_４）_４Ｂ⁻、（Ｃ_６Ｆ_５）_３（ＣＨ_３）Ｂ⁻、（Ｃ_６Ｆ_５）_３（ｎ−Ｃ_４Ｈ_９）Ｂ⁻、（ｐ−ＣＨ_３Ｃ_６Ｈ_４）_３（Ｃ_６Ｆ_５）Ｂ⁻、（Ｃ_６Ｆ_５）_３ＦＢ⁻、（Ｃ_６Ｈ_５）_３（Ｃ_６Ｆ_５）Ｂ⁻、（ＣＨ_３）_２（ｐ−ＣＦ_３Ｃ_６Ｈ_４）_２Ｂ⁻、（Ｃ_６Ｆ_５）_３（ｎ−Ｃ_１８Ｈ_３７Ｏ）Ｂ⁻などである。好ましいボロン中心陰イオンは通常３つ以上のハロゲン置換芳香性炭化水素ラジカルがボロンに取り付けられており、最も好ましいハロゲンはフッ素である。好ましい陰イオンは、（３，５−ｂｉｓ（ＣＦ_３）Ｃ_６Ｈ_３）_４Ｂ⁻、（Ｃ_６Ｆ_５）_４Ｂ⁻、（Ｃ_６Ｆ_５）_３（ｎ−Ｃ_６Ｈ_９）Ｂ⁻、（Ｃ_６Ｆ_５）_３ＦＢ⁻及び（Ｃ_６Ｆ_５）_３（ＣＨ_３）Ｂ⁻などである。
【０１１４】
他の金属を含有する適切な陰イオンは、例えば、（３，５−ｂｉｓ（ＣＦ_３）Ｃ_６Ｈ_３）_４Ａｌ⁻、（Ｃ_６Ｆ_５）_４Ａｌ⁻、（Ｃ_６Ｆ_５）_２Ｆ_４Ｐ⁻、（Ｃ_６Ｆ_５）Ｆ_５Ｐ⁻、Ｆ_６Ｐ⁻、（Ｃ_６Ｆ_５）Ｆ_５Ｓｂ⁻、Ｆ_６Ｓｂ⁻、（ＨＯ）Ｆ_５Ｓｂ⁻、及びＦ６Ａｓ⁻。上に述べたリストはすべてを挙げつくしたものではなく、他の有益なホウ素中心非求核塩類、及びその他の金属や非金属を含んだ有益な陰イオンも（上に示した一般式から）当業者には明らかであろう。
【０１１５】
好ましくは、陰イオンＸ⁻はテトラフルオロボレート、ヘキサフルオロホスフェート、ヘキサフルオロアルセネート、ヘキサフルオロアンチモネート、及びヒドロキシペンタフルオロアンチモネートからなる群から（例えば、エポキシ樹脂などの陽イオン反応種と共に使用するために）選ばれる。
【０１１６】
適切なスルホニウム塩光反応開始剤としては：
トリフェニルスルホニウム、
メチルジフェニルスルホニウム・テトラフルオロボレート
ジメチルフェニルスルホニウム・ヘキサフルオロホスフェート
トリフェニルスルホニウム・ヘキサフルオロホスフェート
トリフェニルスルホニウム・ヘキサフルオロアンチモネート
ジフェニルナフチルスルホニウム・ヘキサフルオロアルセネート
トリトルスルホニウム・ヘキサフルオロホスフェート
アニシルジフェニルスルホニウム・ヘキサフルオロアンチモネート
４−ブトキシフェニルジフェニルスルホニウム・テトラフルオロボレート
４−クロロフェニルジフェニルスルホニウム・ヘキサフルオロホスフェート
トリ（４−フェノキシフェニル）スルホニウム・ヘキサフルオロホスフェート
ジ（４−エトキシフェニル）メチルスルホニウム・ヘキサフルオロアルセネート
４−アセトニルフェニルジフェニルスルホニウム・テトラフルオロボレート
４−チオメトキシフェニルジフェニルスルホニウム・ヘキサフルオロホスフェート
ジ（メトキシスルホニルフェニル）メチルスルホニウム・ヘキサフルオロアンチモネート、
ジ（ニトロフェニル）フェニルスルホニウム・ヘキサフルオロアンチモネート
ジ（カルボメトキシフェニル）メチルスルホニウム・ヘキサフルオロホスフェート、
４−アセタミドフェニルジフェニルスルホニウム・テトラフルオロボレート、
ジメチルナフチルスルホニウム・ヘキサフルオロホスフェート、
トリフルオロメチルジフェニルスルホニウム・テトラフルオロボレート、
ｐ−（フェニルチオフェニル）ジフェニルニルスルホニウム・ヘキサフルオロアンチモネート
１０−メチルフェノキサアシイニウム・ヘキサフルオロホスフェート
５−メチルチアントレニウム・ヘキサフルオロホスフェート
１０−フェニル−９，９−ジメチルチオキサン・ヘキサフルオロホスフェート
１０−フェニル−９−オキソチオキサンテニウム・テトラフルオロボレート
５−メチル−１０−オキソチアントレニウム・テトラフルオロボレート
５−メチル−１０，１０−ジオキソチアントレニウム・ヘキサフルオロホスフェート
などである。
【０１１７】
好ましいスルホニウム塩はトリアリルスルホニウム・ヘキサフルオロアンチモネート（例えば、Ｓａｒｔｏｍｅｒ　Ｃｏｍｐａｎｙから市販されているＳａｒＣａｔ^ＴＭＳＲ１０１０）、トリアリルスルホニウム・ヘキサフルオロホスフェート（例えば、Ｓａｒｔｏｍｅｒ　Ｃｏｍｐａｎｙから市販されているＳａｒＣａｔ^ＴＭ　ＳＲ１０１１）、そしてトリアリルスルホニウム・ヘキサフルオロアンチモニウム（例えば、Ｓａｒｔｏｍｅｒ　Ｃｏｍｐａｎｙから市販されているＳａｒＣａｔ^ＴＭＫ１８５）などのトリアリル置換基である。
【０１１８】
有用なアジニウム塩には、米国特許第４，８５９，５７２号（Ｆｒａｉｄ等）、欄８、行５１〜欄９、行４６に開示されているものなどがあり、それにはピリジニウム、ジアジニウム、あるいはトリアジニウム構成部分などである。アジニウム構成部分は１つ以上の芳香環、通常は炭素環式芳香環（例えば、キノリニウム、イソキノリリウム、ベンソジアジニウム、及びナフトジアゾニウム構成部分）を含んでおり、アジニウム環と融合されている。アジニウム環内の窒素原子の四元化置換基が電子的に励起された状態の光増感剤のアジニウム光反応開始剤への電子移送が起きると遊離ラジカルとして放出される。１つの好ましい形態で、前記四元化置換基はオキシ置換基である。アジニウムの環窒素原子を四元化するオキシ置換基、−Ｏ、−Ｔは種々の合成オキシ置換基から選択することができる。構成部分Ｔは、例えば、メチル、エチル、ブチルなどのアリキル・ラジカルである。アルキル・ラジカルは置換されたものでもよい。例えば、アラルキル（例えば、ベンジル及びフェネチルなど）及びスルフォアルキル（例えば、スルオホメチル）ラジカルなどが役に立つ可能性がある。別の形態で、Ｔは例えば−ＯＣ（Ｏ）−Ｔ^１ラジカルであり、この場合Ｔは上に述べた種々のアルキル及びアラルキル・ラジカルのいずれであってもよい。さらに、Ｔ^１はフェニルやナフチルなどいずれのラジカルであってもよい。アリル・ラジカルは置換されてもよい。例えば、Ｔ^１はトリル又はキシリル・ラジカルであってもよい。Ｔは通常、１〜約１８の炭素原子を含んでいる。各例のアルキル構成部分は好ましくは低級アルキル構成部分であり、各例のアリル構成部分は好ましくは約６〜約１０個の炭素原子を含んでいる。オキシ置換基−Ｏ、−Ｔが１個または２個の炭素原子を含んでいる場合に最高の活性レベルが実現される。アジニウム核は四元化置換基以外の置換基を含んでいてはならない。しかしながら、他の置換基の存在はこれら光反応開始剤の活性にとって絶対に必要なものでもない。
【０１１９】
有益なトリアリルイミダゾイル・ダイマーは米国特許第４，９６３，４７１号（Ｔｒｏｕｔ等）の、欄８、行１８〜２８に述べられているものなのである。これらのダイマーは、例えば、２−（ｏ−クロロフェニル）−４，５−ｂｉｓ（ｍ−メトキシフェニル）−１，１’−ビミダゾール；２，２’−ｂｉｓ（０−クロロフェニル）−４，４’５，５’−テトラフェニル−１，１’−ビミダゾール；そして、２，２’−ｂｉｓ（ｏ−クロロフェニル）−４，４’、５，５’−テトラフェニル−１，１’−ビミダゾル；そして、２，５−ｂｉｓ（ｏ−クロロフェニル）−４−［３，４−ジメトキシフェニル］−１，１’−ビミダゾルなどである。
【０１２０】
好ましい光反応開始剤はヨードニウム塩（より好ましくは２，４，５−トリフェニルイミダゾリル・ダイマー）、スルホニウム塩、そしてジアゾニウム塩などである。より好ましくは、アリルヨードニウム塩、クロロメチル化トリアジン、そして２，４，５−トリフェニルイミダゾリル・ダイマーなどである（アリルヨードニウム及びトリアジンが最も好ましい）。
【０１２１】
光反応性組成物の調製
反応種、多光子光増感剤、電子供与体化合物、そして光反応開始剤は上に述べた方法、あるいは先行技術のその他の方法ででも調製することができ、その多くは市販されている。これら４つの成分はどんな組み合わせ順番及び方法ででも（任意には攪拌しながら）『安全な光』条件下で組み合わせることができるが、光反応開始剤を最後に（そして、他の成分の溶解を促進するために任意に用いられる加熱ステップの後に）加えることが（保存寿命及び熱的安定性の観点から）好ましい。必要であれば溶媒を用いることもできるが、その場合、その溶媒はその組成物の成分とはあまり反応しないように選択されねばならない。適切な溶媒としては、例えば、ジクロロメタン、及びアセトニトリルなどがある。反応種自体が他の成分のための溶媒として機能する場合もある。
【０１２２】
光反応開始剤系の成分は（上に述べたような）光化学的に有効な量で存在している。一般的に、この組成物は重量基準で少なくとも約５％、好ましくは少なくとも約１０％、そしてより好ましくは少なくとも約２０％の１つ以上の反応種を含んでいる。通常、その組成物は重量基準で最大９９．７９％、好ましくは約９５％、そしてより好ましくは最大約８０％の１つ以上の反応種を含んでいる。一般的に、前記組成物は１つ以上の反応種に対する重量を基準として少なくとも約０．０１％、好ましくは約０．１％、より好ましくは少なくとも約０．２％の１つ以上の光増感剤を含んでいる。通常、前記組成物は重量で約１０％、好ましくは最大約５％、そしてより好ましくは最大約２％の１つ以上の光増感剤を含んでいる。好ましくは、前記組成物は少なくとも重量で約０．１％の電子ドナーを含んでいる。好ましくは、前記組成物は重量で約１０％、そして好ましくは約５％の１つ以上の電子ドナーを含んでいる。好ましくは、前記組成物は重量で約０．１％の１つ以上の光反応開始剤を含んでいる。好ましくは、前記組成物は重量で最大約１０％、そして好ましくは最大約５％の１つ以上の光反応開始剤を含んでいる。前記反応種がロイコ染料である場合、前記組成物は通常重量で少なくとも約０．０１％、好ましくは少なくとも約０．３％、より好ましくは少なくとも約１％、そして最も好ましくは少なくとも約２％の１つ以上のロイコ染料を有している。前記反応種がロイコ染料である場合、前記組成物は通常重量で最大約１０％の１つ以上にロイコ染料を含んでいる。これらの割合は溶液ではなく、固体ベース、つまり成分の総重量に基づくものである。
【０１２３】
望ましい最終的使用形態に基づいて、非常に多数の補助剤を含めることができる。適切な補助剤は溶剤、希釈剤、樹脂、結合剤、可塑剤、含量、染料、無機あるいは有機強化あるいな延伸用充填材（好ましい重量は前記組成物総重量の約１０〜９０重量％）、揺変性剤、指示薬、反応抑止剤、安定剤、紫外線吸収剤、薬剤（例えば、浸出可能なフッ化物）などなどである。そうした補助剤の量及びタイプ、そして組成物に添加する方法は当業者には周知である。
【０１２４】
例えば、粘着性を制御し、そして膜形成特性を提供するために前記組成物に非反応性ポリマー性結合剤を含めることはこの発明の範囲内である。そうしたポリマー性結合剤は通常は、前記反応種との共存性を基準として選択される。例えば、反応種に対して用いられるのと同じ溶媒に可溶性で、反応種の反応の過程に悪影響を及ぼす機能基を含んでいないポリマー性結合剤を用いることもできる。結合剤は望ましい膜形成特性と溶液レオロジーを達成するのに適した分子量（例えば、約５，０００〜１，０００，０００ドルトンの範囲、好ましくは約１０，０００〜５００，０００ドルトン、より好ましくは約１５，０００〜２５０，０００ドルトンの範囲）を有している。適切なポリマー性結合剤には、例えば、ポリスチレン、ポリ（メチル・メタクリレート）、ポリ（スチレン）−ｃｏ−（アクリロニトリル）、セルロース・アセテート・ブチレートなどがある。
【０１２５】
露光を行う前に、得られた光反応性組成物を、必要であれば、当業者に知られている（例えば、ナイフ・コーティング及びスピン・コーティングなどを含めて）種々の被覆方法で基板上に被覆することができる。この基質は特定の使用目的や用いられる露光方法に基づいてフィルム、シート、及びその他の面など種々のものから選択することができる。好ましい基板は通常は均一の厚みをもった光反応性組成物の層をつくるのに十分な平坦性を有している。被覆がそれほど必要でない使用例の場合は、その光反応性組成物はバルク形態で露光させることもできる。
【０１２６】
露光システム及びその使用
有用な露光システムは少なくとも１つの光源（通常はパルスレーザー）と少なくとも１つの光学素子を有している。適切な光源は、例えば、アルゴン・イオン・レーザー（例えばＣｏｈｅｒｅｎｔ　Ｉｎｎｏｖａ）でポンピングされるフェムト秒近赤外線チタン・サファイア発振器（例えば、Ｃｏｈｅｒｅｎｔ　Ｍｉｒａ　Ｏｐｔｉｍａ　９００−Ｆ）である。７６ＭＨｚで作動するこのレーザーはパルス幅が２００フェムト秒で、７００〜９８０ｎｍの範囲でチューニングが可能であり、そして平均出力は最大１．４ワットである。しかしながら、実際には、（光反応性組成物で用いられる）光増感剤に適した波長で（多光子吸収を誘起するのに）十分な強度を提供するどんな光源でも用いることができる。そうした波長は通常は約３００ｎｍ〜約１５００ｎｍの範囲であり、好ましくは約６００ｎｍ〜約１１００ｎｍ、より好ましくは約７５０ｎｍ〜約８５０ｎｍの範囲である。ピーク強度は通常は少なくとも約１０^６Ｗ／ｃｍ^２程度である。パルス・フルーエンス（単位面積あたりのパルスあたりのエネルギー）の上限は通常はその光反応性消耗閾値によって示される。例えば、Ｑ−スイッチＮｄ：ＹＡＧレーザー（例えば、Ｓｐｅｃｔｒａ−Ｐｈｙｓｉｃｓ　Ｑｕａｎｔａ−Ｒａｙ　ＰＲＯ）、可視光線染料レーザー（例えば、Ｓｐｅｃｔｒａ−Ｐｈｙｓｉｃｓ　Ｑｕａｎｔａ−Ｒａｙ　ＰＲＯでポンピングされるＳｐｅｃｔｒａ−Ｐｈｙｓｉｃ　Ｓｉｒａｈ）、そしてＱスイッチ・ダイオード・ポンプ・レーザー（例えば、Ｓｐｅｃｔｒａ−Ｐｈｙｓｉｃｓ　ＦＣｃａｒ^ＴＭ）も用いることができる。好ましい光源はパルス長が約１０ナノ秒未満（より好ましくは約１ナノ秒未満、最も好ましくは約１０ピコ秒未満）の近赤外線レーザーである。上に述べたピーク強度とフルーエンスが満たされる限り、その他のパルス長を用いてもよい。
【０１２７】
本発明の方法を実行する上で有益な光学素子は屈折性光学素子（例えば、レンズ及びプリズム）、反射性光学素子（例えば、再帰反射装置、あるは集光ミラー）、回折性光学素子（例えば格子、位相マスク、及びホログラム）、分散装置、Ｐｏｃｋｅｌセル、導波管、波プレート、複屈折性液晶などである。こうした光学素子は集光、ビーム伝送、ビーム／モード整形、パルス整形、及びパルス・タイミングなどの目的のために有益である。通常、光学素子の組み合わせが用いられ、当業者であれば他の組み合わせも容易に想起するであろう。集光度の高い光を提供するために大きな開口数を有する光学装置を用いるのが望ましい場合がしばしばある。しかしながら、望ましい強度特性（及びその空間的配置）を提供する光学素子のどんな組み合わせでも用いることができる。例えば、露光システムは０．７５ＮＡ対物レンズ（Ｚｅｉｓｓ　２０Ｘ　Ｆｌｕａｒ）を備えた走査共焦点顕微鏡（ＢｉｏＲａｄ　ＭＲＣ６００）を用いることもできる。
【０１２８】
通常、光反応性組成物の露光は（上に述べたような）光源をその組成物内での光強度の三次元空間分布を制御するための手段としての光学素子と共に用いることによって行われる。例えば、パルス化データからの光を、その焦点が組成物の体積内に来るように集光レンズを通過させる。この焦点を望ましい形状に対応する三次元パターンに従って走査、あるいは移動させてそれによって望ましい形状をつくることができる。この組成物の露光あるいは光を当てられる体積は、その組成物自体を移動させてでも、あるいは光源を移動させることによっても（例えば、ガルボ・ミラーを用いてレーザー・ビームを移動させることによってでも）走査させることができる。
【０１２９】
光が、例えば、その反応種のものとは異なった可溶性特性を有する物質を作り出す反応を誘発する場合、得られる画像は任意に例えば適切な溶媒を用いて、あるいはその他の周知の方法を用いて露光された、あるいは露光されない領域を除去することで現像される。こうした方法で、複雑な、三次元物体をつくることができる。
【０１３０】
露出時間は通常、画像形成に用いられる露光システムのタイプ（及び開口数、光強度空間分布、レーザー・パルス中のピーク光強度（より高い強度及びより短いパルス継続時間は大雑把に言ってピーク光強度に対応する）などそれに伴う変数）及び露光される組成物の性質（及び光増感剤、光反応開始剤、そして電子供与体化合物の濃度）に依存する。一般的に、焦点領域のピーク光強度をより高くすれば、他のパラメータが同じでも露光時間はより短くなる。直線的な画像形成、あるいは『書き込み』速度は通常、１０^−８−１０^−１５秒（好ましくは約１０^−１１−１０^−１４秒）のレーザー・パルス継続時間、そして１秒あたり１０^２−１０^９パルス（好ましくは約１０^３−１０^８パルス）を用いた場合約５〜１００，０００ミクロン／秒である。
【０１３１】
実施例
本発明の目的と利点をさらに以下の実施例を参照して説明するが、これらの実施例で述べられている具体的な物質と量、及びその他の条件や詳細事項は本発明の範囲を限定するものではない。これらの事例は光反応性組成物内の三次元形状を作り出すための光学素子の使用について述べるものである。
【０１３２】
実施例１
この実施例は多光子吸収プロセスにより光重合化領域を形成するための位相あるいは回折性マスクについて検討する。
【０１３３】
回折マスクの位相プロフィールの計算には均一のエネルギー分布を有する入力ビームを用いる。この実施例においては、計算のために要する時間を減らすために、すべて１つの面上に配置された線の単純な正方形グリッドがテスト・パターンとして機能する。マスクの製造は通常のエッチング技術を通じて行われ、このマスクは回折効率を提供するための４つの位相レベルを有している。
【０１３４】
位相マスクのデザインは１つの平面に一連の焦点あるいは線をつくりだし、焦点長さは１０ミリメートル（ｍｍ）で有効開口数は０．５０である。マスクで発生される一連の焦点ラインはｘあるいはｙ方向の長さが０．５センチメートル（ｃｍ）の線間隔で正方形のグリッドを形成する。書き込みレーザーは８００ナノメートル（ｎｍ）で１キロヘルツ（ｋＨｚ）でパルス幅１２０フェムト秒（ｆｓ）で７５０ミリワット（ｍＷ）を提供する強化Ｔｉ：サファイア・レーザーである。レーザーからのＴＥＭ_００出力は入力ガウス・ビームを０．１ｃｍ×１０．１ｃｍの長方形断面を有する均一エネルギー分布に変換する光学システムに入る。位相マスクの面でのパルスあたりのフルーエンスは１平方センチメートルあたり０．７４ミリジュール（ｍＪ／ｃｍ^２）である。この位相マスクはマスクの底部をサンプル表面から約９．５ｍｍだけ垂直方向に引き離す保持止め具に取り付けられる。マスク取り付けの微少調整によって最終的な焦点位置がサンプルの上部表面に合致させられる。マスク取り付け台とサンプル・ステージは相互に位置合わせ精度で移動する。レーザーからの矩形ビームはそのマスク面に対して垂直に当たり、そのビームの長軸はマスクの短軸と平行である。レーザー・ビームはステージとマスク移動に対しては静止的である。
【０１３５】
厚さ８ｍｍ、直径が１２．７ｃｍ、平均的表面粗度が０．１ミクロメートル（μｍ）を有する磨かれたガラス・ウエハからなるテスト・サンプルはポリマー・コーティングの土台を提供する。多光子反応開始剤である４，４’−ｂｉｓ（ジフェニルアミノ）−トランス−スチルベンを１％負荷されたメチル・ネタクリレート・モノマーの薄層でそのガラス・ウエハの磨かれた側面を被覆した。この重合可能コーティングの組成は４０％ｔｒｉｓ−（２−ヒドロキシエチレン）イソシアネート・トリアクリレート・エステル、５９％メチル・メタクリレート、そして１％の多光子吸着剤の固体成分からなり、ジオキサンに４０重量％で溶解された。この重合化可能物質の層は厚みがほぼ１００μｍである。被覆されたガラス・ウエア上での重合化可能コーティングの露光は位相マスク及びサンプル構造物を前記光学システムから出てくる矩形ビームの短軸に平行な方向に沿って連続的に移動させることで行われる。サンプル・ステージは１００μｍ／秒の均一速度で移動する。光源が位相マスクを走査すると、線のグリッドが重合化可能な層内で光重合化される。
【０１３６】
ＰＭＭＡコーティングをジオキサン内で現像すると、ガラス・ウエハから未反応領域が除去されて、反応した（例えば、光硬化した）ラインが正方形グリッドの形状で出現する。このグリッドを形成する個々のラインは約２０μｍの厚さと約１５μｍの幅を有している。このポリマー性ラインはガラス・ウエハに対して優れた接着性を有している。
【０１３７】
実施例２〜６
これらの実施例で、単一露光経路で、多光子光重合化によって少なくとも部分的に反応された物質の複数の領域を作り出すために光学素子アレイの種々の異なった配列が用いられる。特に注記がない限り、Ａｌｄｒｉｃｈ　Ｃｈｅｍｉｃａｌ　Ｃｏ．，Ｍｉｌｗａｕｋｅｅ，ＷＩから発売されている化学製品が用いられた。
【０１３８】
２光子感光性染料、Ｂｉｓ−［４−（ジフェニルアミノ）スチリル］−１，４−（ジメトキシ）ベンゼンが以下の手順でつくられた。（１）１，４−ｂｉｓ−ブロモメチル−２，５−ジメトキシベンゼンとトリエチル・ホスフェート（Ｈｏｒｎｅｒ　Ｅａｍｏｎｓ試薬）との反応；１，４−ｂｉｓ−ブロモメチル−２，５−ジメトキシベンゼンは文献（Ｓｙｐｅｒ　ｅｔ　ａｌ．，Ｔｅｔｒａｈｅｄｒｏｎ，１９８３；３９，７８１〜７９２）に示されている手順でつくられた。１，４−ｂｉｓ−ブロモメチル−２，５−ジメトキシベンゼン（２５３ｇ、０．７８モル）を１０００ｍＬ丸底フラスコに入れた。トリエチル・ホスフェート（３００ｇ、２．１０モル）を加えた。これらの反応物を窒素雰囲気下で攪拌しながら４８時間加熱した。反応混合物を冷却して、過剰なＰ（ＯＥｔ）_３をＫｕｇｅｌｒｏｈｒ装置を用いて真空内で除去した。望ましい生成物は実際には蒸留されなかったが、Ｋｕｇｅｌｒｏｈｒ装置を用いて過剰なＰ（ＯＥｔ）_３を生成物からの蒸留によって除去した。０．１ｍｍＨｇで１００℃に加熱すると、透明の油分が得られた。冷却して、望ましい生成物が固体として得られた。この生成物は次のステップに直接用いるのに適しており、^１ＨＮＭＲは提案された構造との一致を示していた。トルエンから再結晶化させたところ、無色の針状の結晶が得られ、より純粋な生成物になったが、これはほとんどの場合次のステップのために必要ではなかった。
【０１３９】
（２）Ｂｉｓ−［４−（ジフェニルアミノ）スチリル］−１，４−（ジメトキシ）ベンゼンの合成：１０００ｍＬの丸底フラスコに較正済み滴下じょうごと磁性攪拌器を取り付けた。このフラスコに上の合成から得られた生成物を加え（Ｈｏｒｍｅｒ　Ｅａｍｏｎｓ試薬）（１９．８ｇ、４５．２モル）、そして、Ｎ，Ｎ−ジメチルアミノ−ｐ−ベンズアルデヒド（Ｆｌｕｋａ，２５ｇ、９１．５ミリモル）も加えた。このフラスコを窒素でフラッシュして、セプタで密封した。無水テトラヒドロフラン（７５０ｍＬ）をそのフラスコ内に注入して、すべての固形成分を溶かした。滴下用じょうごにＫＯｔＢｕ（カリウムｔ−ブロキシド）（１２５ｍＬ、１．０ＭをＴＨＦに溶かしたもの）を加えた。フラスコ内の溶液を攪拌し、フラスコ内の内容物に３０分かけてＫＯｔＢｕ溶液を加えた。この溶液を周辺温度下で一昼夜攪拌し続けた。この反応を次にＨ_２Ｏ（５００ｍＬ）を加えて急冷した。この反応物を攪拌し続けたところ、約３０分後に高度に蛍光性の高い黄色の個体がフラスコ内に形成された。この固体をろ過で分離して、空気で乾燥させた。そしてそれをトルエン（４５０ｍＬ）で再結晶化させた。望ましい生成物は蛍光性のある針状結晶（２４．７ｇ、８１％イールド）として得られた。^１ＨＲＭは提案された構造と一致していた。
【０１４０】
実施例２〜５の光源はダイオードでポンピングされたＴｉ：サファイア・レーザー（Ｓｐｅｃｔｒａ−Ｐｈｙｓｉｃｓ）で、８００ｎｍの波長で、パルス幅は約１００ｆｓ、パルス反復速度は８０ＭＨｚ、ビーム直径は約２ｍｍ、そして平均出力パワーは８６０ｍＷであった。光学システムは低分散回転ミラーと、光出力を変えるための光減衰器で構成されていた。最終的な集光要素については各実施例で詳細に述べた。サンプル、あるいはサンプルと最終集光要素の動きはＮｅｗ　Ｅｎｇｌａｎｄ　Ａｆｆｉｌｉｃａｔｅｄ　Ｔｅｃｈｎｏｌｏｇｉｅｓ，Ｉｎｃ．（Ｌａｗｒｅｎｃｅ，ＭＡ）のモーター駆動コンピュータ制御ステージを用いて行われた。
【０１４１】
【表１】

【０１４２】
実施例２
実施例２で、融合シリカ・マイクロレンズ（ＭＥＭＳ　Ｏｐｔｉｃａｌ　ｏｆ　Ｈｕｎｔｓｖｉｌｌｅ，ＡＬから市販されているもの）のアレイを用いて、平行化ビームをサンプル体積内の複数の集光スポットに分割した。このマイクロレンズを六角形アレイに構成し、充填比を７０％とした。各マイクロレンズは直径が７６ミクロンで、開口数は０．５であった。これらのテスト基板で、反応（例えば、光硬化）を前記レンズ・アレイを７０μｍシム上、その基板の上部に位置させて、各マイクロレンズの焦点位置が基板／ポリマー界面上にほぼ一致するようにさせた（図１ａを参照）。
【０１４３】
テスト・サンプルはトリメトキシシリルプロピルメタクリレートを接着性促進剤としての水性エタノールの２％溶液で事前に処理され、その後、光反応性組成物Ｉ（表１）をジオキサン（Ｍａｌｌｉｎｃｋｏｒｄｔ　Ｂａｋｅｒ　Ｉｎｃ．，Ｐｈｉｌｌｉｐｓｂｕｒｇ，ＮＪ）に溶かした固体成分４６％溶液で回転コーティングさせたものガラス製顕微鏡スライドを用いた。被覆されたスライドを８０℃の温度で炉内で１０分間加熱処理して、溶媒を除去した。最終的なフィルム厚みは約３０μｍであった。レンズ・アレイ（３０、図１ａ）とテスト・サンプル（２０、図１ａ）を平行化されたビーム（平均出力：６５０ｍＷ）を用いて１２５μｍ／秒で走査して、０．１ｃｍ^２のエリアを４０秒間露光させた。露光されたサンプルをＮ，Ｎ−ジメチルフォルムアミドで現像して、イロプロピル・アルコール内で洗浄してから、空気中で乾燥させた。図７は実施例２のテスト条件で得られた構造体の走査顕微鏡写真を示している。
【０１４４】
実施例３〜５で、回折性レンズの正方形アレイを用いて、平行化ビームを複数の集光スポットに分割した。レンズ・ピッチは水平及び垂直の両方向で１．０ｍｍで、充填比は１００％であった。各レンズは２波設計、多重レベル回折性要素で、設計上の焦点距離は６３３ｎｍで１０．０ｍｍであった。
【０１４５】
実施例３
実施例３で用いられた装置を図８に示す。この図に示されているように、露光システム６１０は基板６３０上でシム６１２と６１４に保持された回折性レンズ６２０のアレイを含んでいた。アレイ６２０は回折性レンズ６２２を含んでおり、入射光６４０を焦点６１４（つまり、６１４ａ〜６１４ｃ）に集光させた。基板６３０は顕微鏡スライド６３２と界面６３６でスライド６３２上に被覆された保護用組成物層６３４を含んでいた。アレイ６３０の位置は回折性レンズ６２２のピント６１４が基板／ポリマー界面６３６とほぼ一致するように調整された。レーザー・ビームを少なくとも４つの回折性レンズ６２２を完全に満たすように設定されたガリレオ型望遠鏡を用いて約５倍に拡大した。回折性レンズ・アレイ６２０とテスト・サンプル６３０を平行化、拡大レーザー・ビーム（平均出力：２３０ｍＷ）を用いて１２５μｍ／秒で共に走査された。例２で述べたのと同じテスト・サンプルを用意し、露光させて、Ｎ，Ｎ−ジメチルフォルムアムド内で現像し、イソプロピルで洗浄して、空気乾燥させた。
【０１４６】
図９と１０は実施例３の画像形成条件で得られた構造の走査顕微鏡写真を示している。回折性レンズ・アレイの間隔及び左右対称性に対応した反応ポリマーのパターンが示されている。ここのポストの形状は例２の場合より不規則であり、アレイ６２０の集光特性がより複雑であることを示している。
【０１４７】
実施例４
実施例４で、回折性レンズの正方形アレイがレーザー・ビームに対して固定され、基板を下側から走査した。この光学構成によって、複数の画像形成スポットで任意のパターンを作り出すことができた。レーザー・ビームのサイズは少なくとも４つの回折性レンズを完全に満たすように設定されたガリレオ型望遠鏡を用いて約５倍に拡大され、ゾーン・プレートの位置は集光ポイントが基板／ポリマー界面とほぼ一致するように調整された（図８参照）。こうした光学構成を用いていずれの任意のテスト・パターンでも書き込むことができた、この例では、ステージが２つの組み合わさった正方形のテスト・パターンを作り出すようにプログラムされた。実施例２の場合と同じテスト・サンプルを調製し、１２５μｍ（２３０ｍＷ平均レーザー出力）で下側から走査することで露光させた。サンプルをＮ，Ｎ−ジメチルフォルムアムド内で現像し、イソプロピルで洗浄して、空気乾燥させた。図１１は、実施例４の画像形成条件で得られた構造の光学顕微鏡写真を示している。テスト・パターンは４つの異なった画像形成スポットのそれぞれで再現された。ポリマーは基板に対して良好な接着性を示した。
【０１４８】
実施例５
実施例５は、ハイブリッド・ポリマー系のパターン化された光を用いた画像形成について示している。このハイブリッド・ポリマーは熱可塑性基質に反応性モノマーを加えたもので構成されていた。この光反応性組成物の屈折率と密度はポリマー化とそれに続く照射エリアへのモノマー拡散の結果として照射エリアで増大された。望ましい構造体が得られたあと、フィルム全体をその画像を永続的に固定するために１光子光源を用いてブランケット露光させることができる。
【０１４９】
表２に示す光反応性組成物は１，２−ジクロロエタン内に溶解した約４０％溶液として調製され、顕微鏡スライド上に回転コーティングされた。この被覆されたスライドをその後８０℃オーブンで１０分間加熱して、溶媒を取り除いた（最終的なフィルムの厚みは約３０μｍであった）。実施例４の場合と同じ光学構成及びパターンを用いた。基板を１２５μｍ（平均出力：２３０ｍＷ）で走査した。画像形成に続いて、テスト・サンプルを３つのＰｈｉｌｉｐｐｓ　ＴＬＤ　３Ｗ光を４５分間用いて露光させて画像を固定した。
【０１５０】
図１２は屈折率対象画像の光学顕微鏡写真を示している。テスト・パターンは異なった画像形成スポットのそれぞれで再現された。
【０１５１】
【表２】

【０１５２】
実施例６
図１３は実施例６内で用いられた露光システム７１０を示している。Ｃｏｒｎｎｇ　ＳＭＦ−２８単一モード光ファイバーを画像形成用円筒型レンズ７２０の直線アレイとして用いた。実施例２の場合と同じテスト基板７３０を作成した。光ファイバーの外皮をファイバー・ストリッパーを用いて除去し、その後、図１３に示されている未反応テスト・サンプル７３０の表面に軽く押し付けた。そして、基板７３０を平行化レーザー・ビーム７４０（平均出力：６４０ｍＷ）を用いて２５０μｍでラスター走査した。Ｙステージは各走査毎にビーム直径のほぼ半分程度動かした。画像形成に続いて、テスト・サンプルをＮ，Ｎ−ジメチルホルムアミド内で現像して、イソプロピル・アルコールで洗浄して、空気乾燥した。図１４と１５はつくられた高アスペクト比ポリマー・ラインの走査結果を示している。
【０１５３】
実施例７
図１６に示すように、干渉パターン８２０を有するチャープ化格子８１２（例えば、ライン間の間隔が連続フリンジ毎に小さくなるような格子）を平面波８６０と円筒型波８５０の組み合わせによってつくられた干渉フリンジ・パターンを用いて光反応性組成物８３４内に形成した。平行でも逆平行でもない伝播方向を有しており、画像平面に対して入射される）２つの平面波の組み合わせを用いて直線的干渉フリンジが形成された。１つのビームの経路内に円筒型レンズ８４０（レンズ８４０の均一軸は最初の構成からの干渉フリンジ８２６に対して平行）を配置することでチャープ期間を有する平行干渉フリンジ８２６が形成された。この手法は光ブラッグ格子製造に関連した技術分野ではよく知られている（例えば、Ｒ．Ｋａｓｈｙａｐ，Ｆｉｂｅｒ　Ｂｒａｇｇ　Ｇｒａｔｉｎｇｓ，Ａｃａｄｅｍｉｃ　Ｐｒｅｓｓ，１９９９参照）。図１６に示されているように、格子８２０の左端８２２でのフリンジ期間は円筒型レンズがない場合と比較して（入射角度が増大した結果として）より小さくなっている。格子の右端８２４での期間は影響を受けなかった。干渉パターン８２０のチャープ・レートは前記円筒型レンズ８４０の焦点距離を変更するか及び／又はレンズ８４０と干渉面との間の距離を変更するか、あるいは第２のビーム８６０内に（同じ向きの）円筒型レンズを配置することで制御することができる。
【０１５４】
多格子吸収露光システムで用いられる短いパルスは各レーザー・パルス中に干渉パターンの小さな部分を反応させた。従って、ビーム８５０と８６０両方の波長を正確に合致させることで、パルスを重ね合わせて３次元干渉パターン８２０の選択された領域を形成することができた。この波長を合致させる操作はビーム８５０と８６０を個別光遅延ライン（Ｋｉｒｋｐａｒｒｉｃｋ，ｅｔ．ａｌ．，ＡＰｐｌｉ．Ｐｈｉｓ．Ａ，６９，４６１参照）を通過させることで行われた。ビーム波長を相互に対して慎重に調製することで、連続的なレーザー・パルスを用いてチャープされた干渉パターン８２０の部分を反応させることができる。
【０１５５】
実施例８
この実施例では多光子吸収プロセスを用いて複数の光重合価領域を形成するための３−ビーム干渉の使用について検討する。時空における２つのコヒーレントなビーム間の干渉が高及び低強度フリンジを有するパターンをつくりだし、その周期性が入力ビーム間の角度に依存していることは良く知られている。この例で、３つのコヒーレントなパルスレーザー・ビームを用いて明暗領域の２次元アレイを形成して、それを用いて単一の画像形成面に光重合化された領域の対応する２次元アレイを形成した。
【０１５６】
書き込みレーザーは８００ｎｍで８００ｍＷ、１ｋＨｚ、パルス幅１２０ｆｓを作り出す強化Ｔｉ：サファイア・レーザーであった。レーザーからのＴＥＭ_００出力を２つのビーム・スプリッタを通過させて、３つの独立したほぼ同じ強度のビームを発生させた。これらのビームの２つの光学アレイには独立の光遅延ラインとガラス・ウエッジが含まれていた。取り付け台を回転させることで、光経路長を細かく調整することができる。これらのビームを各ビーム間の角度がほぼ１２０度となるように図５に示すようにサンプルで再結合された。光の位置調整のためｎ、最初の２つのビームだけ（一方は遅延ラインを有しており、他方はそれを有していない）だけが干渉しあうようにした。この光遅延ラインの長さはこれら最初の２つのレーザー・ビームからのパルスが、２光子蛍光及びフリンジ干渉パターンの強度の急激な増大の観察で確認されるまで調節された。三番目のビームを次に導入して、再度、その光遅延の長さを、２光子蛍光の強度と干渉パターンの急激な増大が観察されるまで調整された。
【０１５７】
４０重量％酢酸セルロース・ブチレートを含有する溶液（１，２−ジクロロエタンに４０％固形分）（ｎは約１．４６、Ｅａｓｔｍａｎ　Ｃｈｅｍｉｃａｌｓ，Ｋｉｎｇｐｏｒｔ，ＴＮ）、２３重量％フェノキシメタクリレート（Ｓａｒｔｍｅｒ　Ｃｏｍｐａｎｙ，Ｗｅｓｔ　Ｃｈｅｓｔｅｒ，ＰＡ）、３４重量％ビスフェノールＡグリセロレート・ジアクリレート（Ｅｂｅｃｒｙｌ　３７００、ＵＣＳ　Ｃｈｅｍｉｃａｌｓ，Ｓｙｍｒａ，ＧＡ）、２重量％ダイアリーリオドニウム塩（Ｓａｒｔｍｅｒ　Ｃｏｍｐａｎｙ，Ｗｅｓｔ　Ｃｈｅｓｔｅｒ，ＰＡ）、そして１重量％ｂｉｓ−［４−（ジフェニルアミノ）スチリル］−１，４−（ジメトキシ）ベンゼンを調製した。この溶液を約１００ミクロン厚のシリコン・ウエハ上にコーティングして、オーブン内で８０℃で乾燥した。テスト・サンプルをそれら３つのビームがコーティング内で干渉露光して、単一の画像平面上に２次元６角形ハニカム・パターンが得られるように配置した。反応された領域の屈折率モジュレーションが後で反応された基質に対して少なくとも０．００５であった。この被覆を３つのＰｈｉｌｉｐｓ　ＴＬＤ　３Ｗ−０５バルブを用いて、主要出力を４５０ｎｍ、３０分間に設定して、画像全体ではない方法でブランケット露光した。この膜はパターン化された領域に対して少なくとも０．００５の屈折率モジュレーションを維持した。
【０１５８】
ここで引用された特許、特許資料、及び刊行物の開示全体が、それぞれ個々に組み込まれるのと同様に、全体としても本明細書に組み込まれる。本明細書の範囲と精神を逸脱しない範囲で、種々の修正や変更が当業者には容易に想起されるであろう。本発明はここに示されている実施の形態や実例によって限定されるものではなく、それらの例と実施の形態は例として示すだけであり、本発明の範囲は以下に示す請求項によってのみ限定されるものである。
【図面の簡単な説明】
【図１ａ】本発明による微視光学的要素露光システムを示す図。
【図１ｂ】本発明による種々の焦点距離を有する微小レンズを有する微視光学的元素露光システムの別の実施の形態を示す図。
【図１ｃ】非球面軸ずれ微小レンズのアレイを含む別の実施の形態を示す図。
【図２】内部でビーム分割回折性光学素子（ＤＯＥ）が用いられている本発明の回折性光学素子露光システムを示す図。
【図３】内部で波面トランスフォーメーションＤＯＥが用いられている回折性光学素子露光システムを示す図。
【図４】平行平面波と発散球面波を組み合わせて光反応性組成物に干渉パターンを作り出す露光システムを示す図。
【図５】光反応性組成物内の選択した領域で多光子吸収を誘起するための同じ、あるいは実質的に違った波面を有する３つ以上のビームの組み合わせを含む露光システムの１つの実施の形態を示す図。
【図６】微小レンズのアレイから光反応性組成物へのビームを方向操作するために用いられる一連の調節可能な平面鏡を含んでいるシステムを示す図。
【図７】実施例２のテスト条件下で得られる構造の走査電子顕微鏡写真を示す図。
【図８】回折レンズのアレイを含む実施例３で用いられる露光システムを示す図。
【図９】実施例３の画像形成条件で得られた構造の走査電子顕微鏡写真。
【図１０】実施例３の画像形成条件で得られた構造の走査電子顕微鏡写真。
【図１１】実施例４の画像形成条件で得られた構造の光学顕微鏡写真。
【図１２】屈折率対照画像の光学顕微鏡写真。[0001]
Priority claim
This application claims the benefit of US Provisional Application No. 60 / 211,675, filed June 15, 2000, the contents of which are incorporated herein.
[0002]
Field of the invention
The present invention relates to a multiphoton absorption method and a pattern for creating a polymeric three-dimensional structure therefrom.
[0003]
Background of the Invention
Two-photon absorption by molecules was predicted by Goppert-Mayer in 1931. When the pulsed ruby laser was invented in 1960, experimental observations of two-photon absorption became a reality. Since then, two-photon excitation has been applied in biology, optical data storage, and other fields.
[0004]
There are two important differences between a two-photon induced light process and a single photon induced process. Single-photon absorption correlates linearly with incident intensity, but quadratically. Higher order absorptions change at higher orders correlated to that of the incident intensity. As a result, a multiphoton process can be performed with three-dimensional spatial resolution. Also, multi-photon processes involve the simultaneous absorption of two or more photons, and the absorbing chromophore has insufficient energy, even if each photon has enough energy to excite that chromophore. , Are excited by a number of photons whose total energy is equal to the energy of the excited multiphoton photosensitizer. Because the excitation light is not attenuated by single-photon absorption in the cured substrate or material, using a beam focused at that depth in the material allows a greater depth in the material than would be achieved with single-photon excitation. Can selectively excite molecules. These two photons excite, for example, tissue or other biological material. However, such work is limited to slow writing speeds and high laser powers. Therefore, there is a need for a method for improving the throughput and efficiency of a multiphoton absorption system. In multiphoton or stereolithography, the non-linear scaling of intensity and absorption makes it possible to write figures below the diffraction limit of the light, or to draw figures in three dimensions, which is also interesting for holography. That is.
[0005]
Summary of the Invention
The present invention provides various methods and devices for creating regions of at least partially reacted material in a photoreactive composition. In one embodiment, the method comprises providing a photoreactive composition; providing a source of light sufficient for the photoreactive composition to absorb at least two photons simultaneously; Exposure system including at least one diffractive optical element (preferably said diffractive optical element is capable of performing beam splitting, wavefront transformation, or both) and capable of inducing image-like multiphoton absorption Providing a non-random three-dimensional light pattern by the exposure system; and exposing the photoreactive composition to the three-dimensional light pattern generated by the exposure system, at least in part. Reacting a portion of the material in response to the non-random three-dimensional light pattern incident thereon; Tsu contains a flop. "Corresponding" means that the reacted substance need not form an exact copy of the three-dimensional light pattern, although an exact copy is possible.
[0006]
In another embodiment, a method of creating a region of at least partially reacted material in a photoreactive composition comprises providing a photoreactive composition, wherein the photoreactive composition comprises at least two photons. Providing a source of sufficient light to simultaneously absorb light; and providing an exposure system that includes at least one array of diffractive optical elements and is capable of inducing image-like multiphoton absorption; Generating a non-random three-dimensional light pattern by the exposure system; and exposing the photoreactive composition to the three-dimensional light pattern generated by the exposure system to at least partially expose a portion of the material thereto. Reacting in response to the incident non-random three-dimensional light pattern.
[0007]
In yet another embodiment, the method includes providing a photoreactive composition; and providing a source of sufficient light for the photoreactive composition to simultaneously absorb at least two photons. Including a first beam having a first wavefront shape and a second beam having a second wavefront shape, wherein the first wavefront shape is capable of inducing image-like multiphoton absorption. 2 to provide an exposure system that is substantially different from the wavefront shape of FIG. The method further comprises generating a non-random three-dimensional light pattern by the exposure system utilizing optical interference between the first light beam and the second light beam; and generating the three-dimensional light pattern generated by the exposure system. Exposing the photoreactive composition to a three-dimensional light pattern to react at least partially a portion of the material in response to the non-random three-dimensional light pattern incident thereon.
[0008]
In yet another embodiment, the method includes providing a photoreactive composition; and providing a source of sufficient light for the photoreactive composition to simultaneously absorb at least two photons. Can induce image-like multiphoton absorption, includes three or more light beams, each of the three or more light beams includes a wavefront having one shape, and three more. Providing an exposure system wherein each of the above light beams has a non-random three-dimensional light pattern that is the same as or substantially different from the waveforms of the other light beams. The method further includes generating a non-random three-dimensional light pattern by the exposure system utilizing optical interference between the first light beam and the second light beam; and generating the non-random three-dimensional light pattern by the exposure system. Exposing the photoreactive composition to the three-dimensional light pattern to react at least partially a portion of the material in response to the non-random three-dimensional light pattern incident thereon.
[0009]
Various systems are provided for performing various methods according to the present invention. In one embodiment, there is provided an apparatus for reacting a photoreactive composition, the apparatus comprising: a photoreactive composition; and sufficient for the photoreactive composition to simultaneously absorb at least two photons. Including an optical source and at least one diffractive optical element (preferably a diffractive optical element capable of performing beam splitting, wavefront transformation, or both) to induce image-like multiphoton absorption And a non-random three-dimensional light pattern can be generated, a further non-random three-dimensional light pattern can be generated, and the exposure system can generate a non-random three-dimensional light pattern. An exposure system capable of at least partially reacting the unit.
[0010]
In yet another embodiment, there is provided an apparatus for reacting a photoreactive composition, the apparatus comprising a photoreactive composition and a photoreactive composition wherein the photoreactive composition simultaneously absorbs at least two photons. A source of sufficient light and at least one array of refractive optical elements, capable of inducing image-like multiphoton absorption, generating a non-random three-dimensional light pattern, An exposure system that can generate a three-dimensional light pattern and that can at least partially react a portion of a substance in response to the non-random three-dimensional light pattern.
[0011]
In yet another embodiment, the invention provides an apparatus for reacting a photoreactive composition, the apparatus comprising a photoreactive composition and the photoreactive composition simultaneously absorbing at least two photons. A first light beam including a first wavefront shape and a second light beam including a second wavefront shape, wherein the first wavefront shape is the second wavefront shape. It is substantially different from the wavefront shape, can induce image-like multiphoton absorption, can generate a nonrandom three-dimensional light pattern, and can generate a nonrandom three-dimensional light pattern. And an exposure system, wherein the exposure system is capable of at least partially reacting a portion of the substance in response to the non-random three-dimensional light pattern.
[0012]
In yet another embodiment, the present invention provides an apparatus for reacting a photoreactive composition, the apparatus comprising a photoreactive composition and the photoreactive composition absorbing at least two photons simultaneously. Sufficient light source and three or more light beams, each of said three or more light beams including a wavefront having one shape, and further comprising three or more light beams. Each has a wavefront shape that is the same as or substantially different from the waveform of the other light beam, and can also induce image-like multiphoton absorption, generating a non-random three-dimensional light pattern And a further non-random three-dimensional light pattern can be generated, and the exposure system at least partially reacts a portion of the substance in response to the non-random three-dimensional light pattern. Including Kill exposure system.
[0013]
Preferably, the light source is a pulsed laser and the exposing comprises a pulsed irradiation step, which is preferably performed using a near infrared pulsed laser having a pulse length of less than about 10 nanoseconds.
[0014]
Preferably, the photoreactive composition comprises one or more reactive species, one or more multiphoton sensitizers, one or more electron donor compounds, and one or more photoinitiators. . More preferably, the photochemical composition comprises from about 5 to about 99.79% by weight of at least one reactive species and from about 0.01 to about 10% by weight of at least one multi-component based on the total weight of the solids. It contains a photon photosensitizer, up to about 10% by weight of at least one electron donor compound, and about 0.1 to about 10% by weight of at least one photoinitiator.
[0015]
Definition
In this specification,
“Multiphoton absorption” refers to entering a reactive electronically excited state that cannot be reached by simultaneously absorbing two or more photons and absorbing only one photon having the same energy. Means
[0016]
“Simultaneous” means that two events are 10^-14It means that it happens in less than a second.
[0017]
"Electronically excited state" means that it can be reached by absorption of electromagnetic waves and has a lifetime of 10^-13It means the electronic state of a molecule whose energy is higher than the electronic ground state of the molecule, longer than a second.
[0018]
The term "reaction" means curing (polymerization and / or cross-linking) or depolymerization or other reaction.
[0019]
"Optical system" refers to a system that controls light, the system comprising at least one selected from lenses, reactive optics such as mirrors, and diffractive optics such as gratings, and computer generated holograms. The optical element must include a diffuser, a waveguide, and other elements known in the optical arts.
[0020]
“Exposure system” means a combination of an optical system and a light source.
[0021]
"Sufficient light" means light having sufficient intensity and appropriate wavelength to induce multiphoton absorption.
[0022]
"Photosensitizer" refers to a photoinitiator that reduces the energy required to activate a photoreaction initiator by supplying light with low energy required for activation, By a molecule that interacts with the initiator to form a photoinitiating species therefrom.
[0023]
A "photochemically effective amount" (of a component of a photoinitiator system) is defined as the reaction species (density, viscosity, color, pH, refractive index, or other physical or chemical properties, etc.) (Such as) an amount sufficient to cause at least a partial reaction under the selected exposure conditions.
[0024]
"Transit" means that light is completely transmitted through a certain amount of the photoinitiator composition.
[0025]
“Focus” or “focusing” means that the collimated light is concentrated on one point or an image of one object is formed.
[0026]
"Wavefront" means the surface of the stationary phase of a propagating electromagnetic field, for example, light emitted from a point light source has a spherical wavefront.
[0027]
"Substantially different", when used with respect to two or more wavefronts, indicates how well the coherent electromagnetic beams interact when combined. If the optical system used to generate the interference pattern is reconfigured such that the beams are collinear (overlapping, having parallel propagation directions), the interference formed by the combination of the beams The pattern creates at least one bright fringe and one dark fringe in the area of interest in the desired image plane. This suggests that there is a half wavelength difference in the wavefront between the beams in this region.
[0028]
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A common technique for exposing a single grating light confinable (eg, photocurable) material is to expose a large area light source to a reflective or opaque material to select the area to be exposed. Use in combination with a mask. In addition, optics can be incorporated to perform projection lithography to render micron-sized figures. Typically, in such projection systems, the image of the mask is reduced in size and the light is collimated at the image plane so that the light fluence is uniform over the exposed area. A second general technique is to "write" the image directly using, for example, a laser light source and appropriate optics. In this case, the actual pattern is in a computer file and the image is written directly by a computer controlled stage and laser system. The laser spot size is reduced by optics so that even the smallest features of the pattern can be drawn.
[0029]
Multiphoton processes typically require relatively high light fluence at nanosecond-level wavelengths to provide a substantial number of gratings in the initiation region. This high light fluence is achieved by focusing the high energy laser light using a relatively high numerical aperture (NA) lens, for example, a microscope objective. A high NA has a shallow depth of focus and facilitates z-axis control in a multiphoton absorption process. Three-dimensional objects can be processed by precisely moving the laser source in the x, y, and z axes to create the reactants in the desired shape. However, this technique is slow and the accuracy of the movement of the mechanical elements limits the accuracy of the technique.
[0030]
Exposure of large areas of multiphoton-absorbing (eg, curable) materials allows faster processing of large objects. Photopolymerized masks using projection optics do not have the necessary z-axis focusing capability to form complex shapes in three dimensions. The present invention discloses the use of a mask configuration in which the light emitting region includes a refractive element capable of focusing light, for example, to allow sufficient z-axis range determination. As one example, a mask having focusing properties can be made from a photoresist that is photolithographically delimited and then melted to form one or more convex features having a predetermined complex refractive structure.
[0031]
Other processing methods are also suitable (eg, photolytic volume expansion of glass, polymer droplet dispensing, mass transfer, focused ion beam processing, and other micro-light processing methods known in the art). It can be used to create the refraction surface needed to make a range determination.
[0032]
One example of this refractive configuration is shown in FIG. 1a, which shows a micro-optical element exposure system 10 of the present invention. In this figure, a micro-optical element refers to an optical element whose aperture in at least one direction is 5 mm or less. A micro-optical device usually refers to an optical device having a diameter of about 6 mm or less. Fiber is often included in this category. For example, Newport @ Corp. , Irvine @ CA catalog.
[0033]
As shown in FIG. 1 a, a micro-optical element exposure system 10 includes a photo-reactive composition 20 and a micro-optical element array 30. The micro-optical element array 30 is used to focus the incident light 12 to focal points 40 a to 40 e (focal point 40) to induce multiphoton absorption in the photoreactive composition 20. The micro optical element array 30 includes refractive micro lenses 32a to 32e (micro lenses 32) and opaque portions 34a to 34f (opaque portions 34). This opaque portion 34 prevents the incident light 12 from reaching the photoreactive composition 20 through the micro-optical element array 30. These microlenses 32 react with the incident light 12 and focus it on the focal point 40. By moving the photoreactive composition 20 precisely in a direction parallel to or perpendicular to the direction of light irradiation, several identical structures can react at the same time. The width, depth, and orientation of the individual volume elements created within the photochemical composition 20 illuminated by the microlenses 32 may be based on the microoptic array 30 (e.g., incorporating off-axis, aspheric, and distorted mirror surfaces, etc.). Can be controlled by proper design.
[0034]
Similarly, by changing the focal length of each of the micro lenses 32 in the micro optical element array 30, it is possible to change the planar exposure configuration of FIG. 1A to a three-dimensional configuration. Further, the micro-optics need not be arranged in a precise array or have additional elements.
[0035]
An example of a micro-optics exposure system 10 having micro-lenses 32 of different focal lengths is shown in FIG. 1b as another embodiment. In FIG. 1 b, the microlenses 132 of the microoptical element array 130 have different focal lengths to focus the incident light 112 to the focal points 140 at different depths within the photoreactive composition 120. For example, the microlenses 132a have a shorter focal length than the microlenses 132b, and thus focus the incident light 112 to a focal length 140a closer to the surface of the photoreactive composition 120 than the focal point 140b, which is the focus of the microlenses 132b. I do.
[0036]
Simultaneous reaction (eg, curing) of complex three-dimensional structures is also possible by incorporating a beam steering mechanism into the microlens array. The three-dimensional structure is formed by reacting individual areas that are in physical contact but do not overlap using light focused from each microlens. FIG. 1c illustrates such a concept as another embodiment of the present invention. FIG. 1 c shows an array 230 of aspheric, off-axis microlenses 232. Each of the microlenses 232 has a different focal length, and the array is used to simultaneously react (harden) multiple non-overlapping regions at focal points 240a-240e.
[0037]
The preferred method according to the invention focuses the high energy light as if coming from a high numerical aperture numerical aperture objective, but over a large area in three dimensions. The function of the DOE is further divided into two categories: creating an individual array of illuminated areas (beam splitting) and creating a continuous illumination area of a particular shape (wavefront transformation). One DOE can perform both functions. The optical elements of the beam splitting element (see FIG. 2) are similar to those of a refractive microlens, producing a series of focused spots.
[0038]
In FIG. 2, the refractive optical element exposure system 310 includes a photoreactive composition 320 and a refractive optical element 330. DOE 330 diffracts the beam of incident light 312 to a focal point 340 in photoreactive composition 320. As in the case of refractive microlenses (see, for example, FIGS. 1a-1c), the DOE 330 creates an individual focus 340.
[0039]
There are important differences in the way light is used in refractive and diffractive elements. In the case of a refractive element, only the light incident on each microlens is focused and roughened in the photoreactive composition (ie, the light between the microlenses is not focused or reflected and reacts (eg, 1a, and the light 12 incident on the opaque regions 34a-34e is not refracted to the focal point in the photoreactive composition 20. In the case of diffractive, All of the incident light is directed to the desired array pattern (if that element is functioning with high efficiency) (see, for example, FIG. 2), and even though the effective NA of the DOE is higher than that of the individual microlenses. If the value of NA is large, the depth of focus becomes shallow, and the resolution in the z-axis direction increases.
[0040]
In addition, the focus of the microlenses has a particular shape determined by the range defining aperture (eg, a round lens creates a circular Airy diffraction pattern). On the other hand, beam splitting diffractive elements can be designed to create more general shapes, such as squares and rectangles, of “focus spots”. Wavefront transformation diffractive optics transform the incident light field into a semi-continuous pattern at a more general, desired location.
[0041]
FIG. 3 shows another embodiment of the present invention in which a wavefront transformation DOE is used. As shown, the diffractive optical element exposure system 350 includes a wavefront transformation DOE 370 and a photochemical composition 360. The incident light 352 is diffracted by the DOE 370 into a semi-intermittent non-random three-dimensional light pattern 380.
[0042]
Both types (beam splitting and wavefront transformation) DOEs are used to concentrate light from a large area incident beam into a smaller spatial region of the photochemical composition to cause a reaction. If the diffractive element is functioning like one or more refractive lenses (ie, if one or more small size focusing spots are created), the resulting light collection pattern will be It has a similar depth of focus characteristic to that achieved (depending on the DOE design method). When complex light patterns are created through wavefront transformation, the behavior of the light field away from the light surface becomes more complex. In special cases (long, narrow patterns, etc.), the DOE obtained in DOE may be different in two directions perpendicular to the optical axis. This property can be used to advantage in forming certain structures.
[0043]
One possible method that can be used to design the DOE (when close to the axis) uses an iterative Fourier transform algorithm that simulates light field propagation between the diffractive element and the image plane. The desired light field intensity distribution at the image plane and the processing constraints of the diffractive element serve as limits to converge the design of the diffractive element. (Other paraxial and non-paraxial methods useful in the design of DOEs are also known in the art). Generally, the complexity and resolution of the particular image formed by the diffractive element is controlled by the method used to fabricate the diffractive element (as well as the efficiency of the diffractive element). The optical phase function calculated in the above process is usually coded in the DOE as a surface relief profile (other methods can be used).
[0044]
The exact structure of the DOE has a significant effect on the optical efficiency available (defined by the percentage of light directed to the desired area or direction). The DOE is typically configured as a surface relief pattern in a transparent or reflective material having a multi-step profile approximating a continuous profile that occurs in the design process. The DOE efficiency increases with the number of levels used in the approximation process, with the continuous profile having the highest efficiency. The overall efficiency depends on whether the calculated optical phase function used to form the DOE is constrained to be separable in the in-plane coordinate system, and the diffraction efficiency of the nonseparable phase function Is substantially higher. The smallest horizontal feature that can be created in the DOE processing process limits the effective numerical aperture that controls the smallest feature that can be resolved in the DOE image plane.
[0045]
The diffractive element can be processed by a well-known method such as creating a coherent (for example, laser) light and recording an interference pattern thereof, a well-known algorithm, or a configuration of a surface relief. The desired phase profile is formed on the surface of the material by, for example, either selective chemical or physical etching, direct writing of a developable photosensitive resin (using an electron beam or laser), or laser ablation. be able to. In all cases, the phase function recorded on the diffractive element changes the phase information of the incident light wave, directing the wave in a predetermined direction.
[0046]
Some examples of multiphoton absorption as a processing method using holography have been published (for example, TJ Bunning, et. Al., Chem. Mater., 12, 2842 {and} C. Diamond, et. al., Opt.Express, 6 (3), 64). In both of these instances, interference between beams having approximately the same wavefront shape is used to create an interference pattern that reacts with the photoreactive composition (eg, cures, etc.) (and results in a periodic reaction line). . In the first case, two collimated beams (not parallel or anti-parallel) are incident on the composition of the present invention. In a second example, the two beams are combined and focused on the same surface using another part of the same lens. In both cases, the two beams had approximately the same waveform, differing only in the direction of propagation.
[0047]
The present invention discloses a combination of two beams having substantially different wavefronts to induce multiphoton absorption in designated regions. The energy of the beam here is insufficient to cause multiphoton absorption, but the energy at the interference maximum is sufficient to induce multiphoton absorption by the photoreactive composition. The use of two substantially different beams can create interference patterns that do not form a regular array.
[0048]
One embodiment of such a structure is shown in FIG. In this figure, an exposure system 410 combines a collimated plane wave 420 and a diffuse spherical wave 430 to create an interference pattern 440 without a photoreactive composition 450. The interference pattern 440 formed by the combination of these two beams 420 and 430 from one continuous wave light source is a series of concentric circles 442. When a short pulse is used in multiphoton absorption, pulses can be overlapped by precisely matching the path lengths of the two beams, and an interference pattern in a specified area is formed. By carefully adjusting the path length of one beam to the other, successive laser pulses can react different parts of the interference pattern. Although this embodiment includes only one case of combining a plane wave and a spherical wave, various optical elements can be arranged on any beam to precisely adjust the shape of each wavefront, and to adjust the curve and / or variation. It is possible to create a reaction area corresponding to an interference pattern having periodic lines.
[0049]
The present invention also discloses a combination of three or more beams having the same or substantially different wavefronts to cause multiphoton absorption in designated areas. FIG. 5 shows one embodiment of such a structure. In FIG. 5, exposure system 460 includes incident light 470 including light beams 472a, 472b, and 472c (light beam 472), and photochemical composition 480. Each of the light beams 472 includes a collimated plane wave 474 (i.e., edge waves 474a, 474b, and 474c). Plane wave 474 has a non-parallel propagation direction. The plane waves 474 combine to form an interference pattern 490 in the photoreactive composition 480. The interference pattern 490 formed by the combination of these three light beams 472 is an array of intensity maxima in a grid configuration 492. FIG. 5 shows intensity maxima 492 on a particular plane. However, interference fringes occur throughout three dimensions. If short pulses are used for multiphoton absorption, the pulses can overlap to form a designated area of the three-dimensional interference pattern 490 by accurately matching the path lengths of these three beams 472. By carefully aligning each of the beam path lengths with the other, successive laser pulses can be used to react different regions of the interference pattern 490.
[0050]
Although this embodiment shows a simple case where three similar plane waves 474 are used to create an interference pattern 490, the shape of each wavefront is precisely adjusted to accommodate complex three-dimensional light patterns. Various optical elements may be arranged without these three beams 472 to create a reaction region in a three-dimensional pattern.
[0051]
The multi-photon absorption embodiments described above use stationary refractive and diffractive elements. The present invention can be extended by incorporating operable optical elements into the optical system to allow dynamic control of the light pattern used to react the photoreactive composition.
[0052]
One such embodiment is shown in FIG. 6, where an array of plane mirrors 540 that can be adjusted to control the direction of a beam 550 from a row of microlenses 530 to a photoreactive composition 520 is provided. Used. By adjusting the angle of each mirror 540, the beam 550 can be steered into a non-overlapping volume of the photoreactive composition (eg, focal points 522a-522c).
[0053]
The present invention is not limited to optical systems incorporating the movable micromirrors described above, but includes electronically configurable polymer dispersed liquid crystal lenses, deformable mirrors commonly used in applicable optical systems, and the like. Reflective, refractive, and diffractive optical elements can be included. By combining such tunable optics and a signal that controls a precision translation stage holding the photoreactive composition, the total exposure time of complex three-dimensional structures in the photoreactive composition is significantly reduced. be able to.
[0054]
Note that the complete optical system has been optimized to handle pulse widths in the femtosecond to nanosecond range. Femtosecond light pulses have a length on the order of micrometers and can be used in optical designs (micro-optic, diffractive, or coherent) to provide very small and complex three-dimensional structures. Zu).
[0055]
The system for multiphoton absorption comprises a light source and suitable optics, at least one photoreactive composition, at least one multiphoton photosensitizer, optionally at least one electron donor, optionally the photoreactive composition An exposure system comprising at least one photoinitiator for The photoreaction initiator may or may not be used usually except when the reactive species is a cationic resin.
[0056]
Exposure systems useful in the present invention include a light source, typically a laser, and appropriate optics. A laser light source useful in the present invention is pumped, for example, with an argon ion laser (Coherent Innova 310) incorporated in a laser scanning confocal microscope (BioRad MRC600) with a 0.75 NA objective (Zeiss 20X Fluar). Femtosecond near-infrared titanium-sapphire oscillator (such as Coherent # 900-F). Operating at 76 MHz, the laser has a pulse width of 100 femtoseconds, is tunable from 700 nm to 1000 nm, and has a bandwidth of 10 nm (fwhm). In fact, any suitable light source that can provide sufficient light energy at the appropriate wavelength for the photosensitizer used in the photoreaction system (see below) may be used.
[0057]
Optical elements useful in the present invention are refractive, reflective, diffractive, diffusive, diffuser, waveguide, and the like. Refractive optical elements include lenses, mirrors, prisms, and the like. Diffractive optical elements include gratings, phase masks, holograms, and the like. The reflective optical element includes a retroreflector, a collecting mirror, and the like. Many other optical elements known to those skilled in the art can also be used. For example, diffusers, pocket cells, waveguides, phase plates, birefringent liquid crystals, and the like.
[0058]
Reactive species
Reactive species that have been introduced for use in photoreactive compositions include curable and non-curable species. Curable species are generally preferred, for example, addition-polymerizable monomers and addition-crosslinkable polymers (free-radically polymerizable or crosslinkable ethylenically unsaturated species such as certain vinyl compounds such as acrylates, methacrylates, and styrene). ) And cationically polymerizable monomers and oligomers (eg, epoxies, vinyl ethers, cyanates, etc.) and polymers that are cationically crosslinkable, or mixtures thereof.
[0059]
Suitable ethylenically unsaturated species are described, for example, in U.S. Patent No. 5,545,676 to Palazzotto et al., Column 1, line 65 to column 2, line 26 and include mono-, di-, and poly- -Acrylates and methacrylates (e.g. methyl acrylate, methyl methacrylate, ethyl acrylate, isopropyl methacrylate, n-hexyl acrylate, stiaryl acrylate, allyl acrylate, glyceryl diacrylate, glycerol triacrylate, ethylene glycol Diacrylate, diethylene glycol diacrylate, triethylene glycol dimethacrylate, 1,3-propanediol diacrylate, 1,3-propanediol dimethacrylate, triethylolpropane tria Acrylate, 1,2,4-butanetriol trimethacrylate, 1,4-cyclohexanediol diacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, pentaerythritol tetramethacrylate, sorbitol hexaacrylate Bis [1- (2-acryloxy)]-p-ethoxyphenyldimethylethane, bis [1- (3-acryloxy-2-hydroxy)]-p-propoxyphenyldimethylmethane, trisidoxyethyl-isocyanurate. Trimethacrylate, bis-acrylate and bis-methacrylate of polyethylene glycol having a molecular weight of about 200-500, copolymer of acrylated monomers as disclosed in U.S. Pat. No. 4,652,274. Possible mixtures, and acrylated oligomers as disclosed in U.S. Pat. No. 4,642,126; unsaturated amides (e.g., methylene bis-acrylamide, methylene bis-acrylamide, methylene bis-methacrylamide, 6-hexamethylene bis-acrylamide, diethylene triamine tris-acrylamide and beta-methacrylaminoethyl methacrylate); vinyl compounds (such as styrene, diallyl phthalate, divinyl succinate, divinyl adipate, and divinyl phthalate, and the like); Suitable reactive polymers include pendant (meth) acrylates having from about 1 to about 50 (meth) acrylate groups per polymer chain. Examples of such polymers include aromatic (meth) acrylate half-ester resins such as Sarbox ™ resin commercially available from Sartomer (eg, Sarbox ™ 400, 401, 402, 404, and 405). Other useful reactive polymers that can be cured by free radicals include polymers having a hydrocarbon backbone and associated peptide groups and having a free radical polymerizable function attached thereto, such as U.S. Pat. No. 5,235,015 (Ali et al.) Correspond thereto. If desired, mixtures of two or more monomers, oligomers and / or reactive polymers can also be used. Preferred among the ethylenically unsaturated species are acrylates, aromatic acrylate (meth) acrylate half-ester resins, and a free radical polymerizable function having a hydrocarbon backbone and associated peptide groups attached thereto. Polymer.
[0060]
Suitable cationic reactive species are disclosed by Oxman et al. In, for example, U.S. Patent Nos. 5,998,495 and 6,025,406, and include epoxy resins. These materials, also called epoxides, include monomeric epoxy compounds and epoxides of the polymeric type, and may be fatty, cycloaliphatic, aromatic, and heterocyclic. These materials typically have on average one (preferably about 1.5, and more preferably at least about two) polymerizable epoxy groups per at least one molecule. These polymerized epoxides include linear polymers having terminal epoxy groups (eg, diglycidyl ether of polyoxyalkylene glycol), polymers having backbone oxytan units (eg, polybutadiene polyepoxide), and polymers having accompanying epoxy groups. (Eg, glycidyl methacrylate polymer or copolymer). The epoxide may be a pure compound or a mixture of compounds containing one, two, or more epoxy groups per molecule. For example, the backbone can be of any type, and the substituents thereon can be of any type so long as they do not substantially affect cationic cure at room temperature. You may. Examples of substituents that can be used include halogen, ester, sulfonic, siloxy, nitro, and phosphate groups. The molecular weights of these epoxy-containing materials range from about 58 to about 100,000 or more.
[0061]
Useful epoxy-containing materials include those containing cyclohexene oxide groups, such as epoxycyclohexanecarboxylate; representative examples are 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, 3,4-epoxycyclohexanecarboxylate. Epoxy-2-methylcyclohexylmethyl-3,4-epoxy-2-methylcyclohexanecarboxylate and bis (3,4-epoxy-6-methylcyclohexylmethyl) adipate. A more detailed list of useful epoxides having such properties can be found in U.S. Pat. No. 3,117,099.
[0062]
Other useful epoxy-containing materials include
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Wherein R 'is alkyl or allyl, and n is an integer in the range of 1-6. Examples are glycidyl ethers of polyhydric phenols obtained by reacting polyhydric groups with an excess of chlorohydrin such as epichlorohydrin (eg 2,2-bis- (2,3-epoxypropoxyphenol) -propane). )and so on. Yet another example of this type of epoxide is described in U.S. Pat. No. 3,018,262 and further described in Handbook of Epoxy Resins, Lee and Neville, McGraw-Hill Book Co. , New @ York (1967).
[0063]
Numerous commercially available epoxy resins can also be used. In particular, readily available epoxides include actadecylene oxide, epichlorohydrin, styrene oxide, vinyl oxide cyclohexene, glycidol, glycidyl methacrylene, diglycyl ether of bisphenol A (eg, Resolution @ Performance Products Inc., formerly from Shell Chemicals Co.). Epon on sale^TM828, Epon^TM825, Epon^TM1004 and Epon^TM1010, and Dow Chemical Co. DER released by^TM-331, DER^TM-332 and DER^TM-334, etc.), vinylcyclohexene (eg, ERL-4206, available from Union Carbide Corp.), 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexene carboxylate (eg, from Union Carbide Corp.). Commercially available ERL-4221 or Cyracure^TMUVR @ 6110 or UVR @ 6105), 3,4-epoxy-6-methylcyclohexylmethyl-3,4-epoxy-6-methyl-cyclohexene carboxylate (e.g., ERL-4201 from Union Carbide Corp), bis (3,4 -Epoxy-6-methylcyclohexylmethyl) adipate (e.g. ERL-4289 from Union Carbide Corp), bis (2,3-epoxycyclopentyl) ether (e.g. ERL-0400 from Union Carbide Corp), modified from polypropylene glycol. Fatty epoxies (e.g., ERL-4050 and ERL-4052 from Union Carbide Corp), dipentene dioxide (e.g., Union Carbide). Of e Corp ERL-4269), epoxidized polybutadiene (e.g., FMC Corp Oxiron^TM2001), a silicone resin having an epoxy function, a flame-retardant epoxy resin (for example, DER which is an epoxy resin of the oxalated bibisphenol type commercially available from Dow Chemical Co.)^TM-580), 1,4-butanediol diglycyl ether of phenolaldehyde novarak (eg, DEN from Dow Chemical Co)^TM-431 and DEN^TM-438), resortinol diglycidyl ether (e.g., Koporite from Koppers @ Company, Inc.)^TM), Bis (3,4-epoxycyclohexyl) adipate (e.g., ERL-4299 or UVR-6128 from Union Carbide Corp), 2- (3,4-epoxycyclohexyl-5,5-spiro-3,4-epoxy) Cyclohexane-meta-dioxane (e.g., ERL-4234 from Union Carbide Corp), vinylcyclohexene 1,2-epoxyhexadecane (e.g., UVR-6216 from Union Carbide Corp), alkyl C₈-C₁₀Glycyl ether (e.g., Heloxy from Resolution Performance Products)^TM{Modifier 7), alkyl C₁₂-C₁₄Glycyl ether (e.g., Heloxy from Resolution Performance Products)^TMModifier 8), butyl glycidyl ether (eg, Heloxy from Resolution PerformanceｓProducts)^TMModifier 61), cresyl glycidyl ether (eg, Heloxy from ResolutionＲPerformanceｓProducts)^TM{Modifier 62), p-tert-butylphenyl glycidyl ether (e.g., Heloxy from Resolution Performance Products).^TMMultifunctional glycidyl ethers such as Modifier 65), glycidyl ether of 1,4-butanediol (eg, Heloxy from Resolution Performance Products)^TM６７Modifier 67), glycidyl ether of neopentyl glycol (eg, Heloxy from Resolution Products Products)^TMModifier 68), diglycyl ether of cyclohexanedimethanol (eg, Heloxy from Resolution Products Products)^TMModifier 107), trimethylol ethane ether (eg, Heloxy from Resolution Performance Products)^TMModifier 44), trimethylol propane triglycyl ether (eg, Heloxy from Resolution Performance Products)^TMModifier48), a polyglycyl ether of a fatty polyol (eg, Heloxy from Resolution Products Products)^TMModifier 84), polyglycol diepoxide (eg, Heloxy from Resolution Products Products)^TM@Modifier 32), bisphenol F epoxide (e.g., Epon sold by Ciba-Geigy Corp.)^TM-1138 or GY-281), and 9,9-bis [4- (2,3-epoxypropoxy) -phenyl] fluorenone (e.g., Epon from Resolution {Performance} Products).^TM1079).
[0064]
Other useful epoxy resins include one or more copolymerizable vinyl compounds of glycidyl acrylates (such as glycidyl acrylate and glycidyl methacrylate). Examples of such copolymers include 1: 1 styrene-glycidyl methacrylate, 1: 1 methyl methacrylate-glycidyl acrylate, and 62.5: 24: 13.5 methyl methacrylate-ethyl acrylate-glycidyl methacrylate. Other useful epoxy resins are well known and include epichlorohydrin, alkylene oxides (eg, propylene oxide), styrene oxide, alkenyl oxides (eg, butadiene oxide), and glycidyl esters (eg, ethyl Glycidate).
[0065]
Useful epoxy-functional polymers are described in U.S. Pat. No. 4,279,717 (Eckberg) and include epoxy-functional silicones such as those commercially available from General Electric Company. These are polymethylsiloxanes in which 1 to 20 mol% of the silicon atoms have been replaced by epoxyalkyl groups (preferably epoxy cyclohexylethyl as described in U.S. Pat. No. 5,753,346 (Kessel)). It is a thing.
[0066]
Mixtures of various epoxy-containing materials can also be used. Such mixtures have a weight average molecular weight distribution of two or more of the epoxy-containing compounds (eg, low molecular weight (less than 200), intermediate molecular weight (about 200-10,000), and high molecular weight (greater than about 10,000)). ing. Alternatively or additionally, the epoxy resin may comprise a mixture of epoxy-containing materials having different chemical properties (such as fatty and aromatic) or functionalities (polar and non-polar). Other cationically reactive polymers (eg, vinyl ether, etc.) can be added if desired.
[0067]
Preferred epoxies include aromatic glycidyl epoxides (e.g., Epon, available from Resolution Performance Products).^TMAnd cycloaliphatic epoxies (such as ERL-4221 and ERL-4299 sold by Union Carbide).
[0068]
Suitable cationic reactive species are also vinyl ether monomers, oligomers, and reactive polymers (eg, methyl vinyl ether, ethyl vinyl ether tert-butyl vinyl ether, isobutyl vinyl ether, triethylene Glycol divinyl ether (Rapi-Cure, commercially available from International \ Specialty \ Products, Wayne, NJ)^TM@ DVE-3), trimethylolpropane trivinyl ether (TMPTVE, commercially available from Base Corp., Mount Olive, NJ), and Vectomer from Allied Signal.^TMDivinyl ether resin (for example, Vectomer^TM2010, Vectorer^TM2020, Vector^TM4010, and Vector^TM4020 and its equivalents first published by other manufacturers)) and mixtures thereof. Mixtures (in any proportion) of one or more vinyl ether resins and / or one or more epoxy resins can also be used. Polyhydroxy functional materials (eg, US Pat. No. 5,856,373 (Kaisaki et al.)) Can also be used in combination with epoxy and / or vinyl ether functional materials.
[0069]
Uncured species include, for example, reactive polymers whose solubility is increased by acid or radical induced reactions. Such reactive polymers include, for example, water-insoluble polymers that contain ester groups that can be converted to water-soluble acid groups by a photogenerated acid, such as poly (tert-butoxycarbonyloxystyrene). Resins include RD Allen, GM, Wallaff, WD, Hinsberg, and L. L. Simpton, "High Performances, Acrylic, Polymers, for Chemicals, A.P.A., J.P.A., Ltd. , 9, 3357 (1991), there are chemically amplified photoresists, the concept of which is now known. Are widely prevalent in the microchip manufacturing industry, in particular, they are known to have properties below 0.5 micron (or even 0.2 micron), and such photoresists are exposed to catalytic species (usually hydrogen ions). , Which involves a series of chemical reactions, where hydrogen generates more hydrogen ions and other acidic species, thereby increasing the rate of the reaction. Examples of typical acid catalyzed chemically amplified photoresist systems include deprotection (e.g., t-butoxycarbo as described in U.S. Pat. No. 4,491,628). Niloxystyrene resist, a totrahydropyran (THP) film as described in U.S. Pat. No. 3,779,778. Acrylates, THP-phenolics, and t-butyl methacrylates as described by PD Allen et al. In Proc. SPIE, 2438, 474 (1995)); , Polyphthalaldehyde-based substances); and reconstitution (eg, a substance based on pinacol reconstitution).
[0070]
Beneficial non-curable species also include leuco dyes, which remain colorless until oxidized by the acids generated by the multiphoton photosensitizer system and become visible when oxidized Tends to show color. (Oxidized dyes develop color by absorbing light in the visible portion of the electromagnetic spectrum (about 400-700 nm)). Leuco dyes useful in the present invention are those that are reactive and oxidizable under normal oxidizing conditions, but are less reactive and do not oxidize under normal environmental conditions. Many of these chemical types of leuco dyes are known to chemists in the imaging arts.
[0071]
Leuco dyes useful in the present invention include acrylated leuco azines, phenoxazines, phenothiazines and the like, which are partially
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Where X is O, S, and -NR.¹¹R is selected from the group consisting of¹And R²Is selected from H and an alkyl group having 1 to about 4 carbon atoms,³, R⁴, R⁶And R⁷Is independently H and an alkyl group of 1 to about 4 carbon atoms, preferably methyl;⁵Is an alkyl group having 1 to about 16 carbon atoms, an alkoxy group having 1 to about 16 carbon atoms, and an allyl group having up to 16 carbon atoms;⁸Is -N (R¹) (R²), H, an alkyl group having 1 to about 4 carbon atoms (R¹And R²Is selected and defined as above); R⁹And R¹⁰Is selected from H and an alkyl group having 1 to about 4 carbon atoms, respectively;¹¹Is selected from an alkyl group having 1 to about 4 carbon atoms and an allyl group having up to 11 carbon atoms (preferably a phenyl group). The following compounds are examples of this type of leuco dye.
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[0072]
Other useful leuco dyes include Leuco Crystal Violet (4,4 ', 4 "-methylidenetris- (N, N-dimesylaniline), Leuco Malachite Green (p, p'-benzylidenebis- (N, N-dimethyldiamine)), Leuco @ Atacryl \ Orange-LGM (color index Basic \ Orange \ 21, Comp. No. 48035 (Fisher base type compound)) having the following structure:
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Leuco Atacryl Brillant Red-4G having the following structure (Color Index Basic Red 14)
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Leuco Atacryl Yellow-R having the following structure (Color Index Basic Yellow 11, Comp. No. 48055)
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Leuc Ethyl Violet (4,4 ', 4' '-methylidenetris- (N, N-diethylaniline), Leuco Victoria Blue-BGO (Color Index Basic Blue 728a, Comp. No. 44040; 4,4'-methylidene) -(N, N-diethylaniline) -4- (N-ethyl-1-naphthalamine), and Leuco Atlantic Fuchsime Crude (4,4 ', 4 "-methylizinetris-aniline).
[0073]
The leuco dye is usually at least about 0.01% by weight (preferably at least about 0.3% by weight, more preferably at least about 1% by weight, and most preferably, based on the total weight of the photosensitizing layer, (At least about 2-10% by weight). Binders, stabilizers, surfactants, antistatic agents, coatings, lubricants, fillers, etc. may also be present in the photosensitizing layer. One skilled in the art will readily know the desired amount of additive. For example, the amount of filler is selected so that undesired scattering at the writing wavelength does not occur.
[0074]
If desired, mixtures of different types of reactive species can be used in the photoreactive composition. For example, mixtures of free radical-reactive species and cationic reactive species, mixtures of curable and non-curable species, and the like are also useful.
[0075]
Photoinitiator system
(1) Multiphoton photosensitizer
Multiphoton photosensitizers suitable for use in photoreactive compositions in a multiphoton photoinitiator system are those that can simultaneously absorb at least two photons when exposed to sufficient light. Preferably, they have a larger two-photon absorption cross section than that of fluorescein (i.e., larger than that of 3 ', 6'-dihydroxyspiro [isobenzenefuran-1 (3H), 9'-[9H] xanthen] 3-one. Absorption section). Generally, this cross section is C.I. Xu and W.C. W. Webb @ in @ J. Opt. Soc. Am. B, 13, 481 (1996), which is also quoted by the method described in International Publication No. WO 98/21521, p. 85, lines 18-22 by Marder @ and @ Perry et al. 50 × 10^-50cm⁴Seconds / photon or more.
[0076]
The method includes a step of comparing the two-photon fluorescein intensity of the photosensitizer with that of a reference compound (under the same excitation intensity and photoinitiator concentration conditions). The reference compound can be selected to fit as closely as possible the spectral range covered by the photoinitiator absorption and fluorescence. In one possible experimental setting, the excitation beam can be split into two arms such that 50% of the excitation intensity enters the photosensitizer and the remaining 50% enters the reference. The relative fluorescence intensity of the photosensitizer with respect to the reference compound can be measured with two photomultiplier tubes or other calibrated detection devices. Finally, the fluorescence quantum efficiency of both compounds can be measured in a one-photon excitation situation.
[0077]
Methods for determining fluorescence and phosphorescence quantum yield are well known in the art. Generally, the area under the fluorescence (or phosphorescence) spectrum of the compound in question is compared under the fluorescence (or phosphorescence) spectrum of a standard luminescent compound having a known fluorescence (or phosphorescence) quantum yield, and Appropriate corrections are made (taking into account the optimal density of the composition at the excitation wavelength, the shape of the fluorescence detector, the difference in emission wavelength, and the response of the detector to different wavelengths). Standard methods are described, for example, in Handbook of Fluorescence, Spectra, of Aromatic, Moleculars, Second Edition, pages 24-27, Academic Press, New York (1971). B. By Berlinman, J. et al. Phys. Chem. , 75, 991-1024 (1971). N. Demas @ and @ G. A. By Crosby; Phys. Chem. , 80, 969-974 (1976). V. Morris, M .; A, Mahoney.
[0078]
Assuming that the emission states are the same under one or two photon excitation (a common assumption), the two-photon cross section (δ_sam) Is δ_refK (I_sam/ I_ref) (Φ_sam/ Φ_ref), Where δ_refIs the two-photon absorption cross section of the reference compound,_samIs the fluorescence intensity of the photosensitizer, I_refIs the fluorescence intensity of the reference compound, φ_samIs the fluorescence quantum efficiency of the photosensitizer, φ_refIs the fluorescence quantum efficiency of the reference material, and K is a correction factor to account for slight differences in light path and response of the two detectors. K can be determined by measuring the response to the same photosensitizer in both the sample and the reference arm. In order to make an effective measurement, a clear quadratic dependence of the two-photon fluorescence intensity on the excitation power can be ascertained, and relatively low concentrations of both the photosensitizer and the reference compound (fluorescence reabsorption). (To avoid photosensitizer aggregation effects).
[0079]
If the photosensitizer is not fluorescent, the yield of the electronically excited state can be measured and compared to known standards. In addition to the methods described above for determining the fluorescence yield, various methods for measuring the excited state yield are known (eg, transient absorption, phosphorescence yield, photochemical reaction product or photosensitizer ( Disappearance from photoreactions).
[0080]
Preferably, the two-photon absorption cross section of the photosensitizer is about 1.5 times or more that of fluorescin (in other words, about 75 × 10 5 as measured by the above method).^-50cm⁴Sec / photon or more, and more preferably about twice or more of fluorescin (in other words, about 100 × 10^-50cm⁴Seconds / photon or more, most preferably about 3 times or more of fluorescin (in other words, about 150 × 10^-50cm⁴Seconds / photon or more, optionally about 4 times or more of fluorescin (in other words, about 200 × 10^-50cm⁴Second / photon or more).
[0081]
Preferably, the photosensitizer is soluble in the reactive species (if the reactive species is a liquid) and is compatible with the reactive species and any binder (as described below) contained in the composition. It is possible. Most preferably, the photosensitizer uses the test procedure described in U.S. Pat. No. 3,729,313 to cover a wavelength range that overlaps its non-hub single photon absorption spectrum (single photon absorption conditions). , The 2-methyl-4,6-bis (trichloromethyl) -s-triazine can be made photosensitive. Using currently available materials, this test can be performed as follows.
[0082]
The following composition: That is, 5 parts (by weight) of a 5% by weight solution dissolved in 45,000 to 55,000 molecular weight of methanol, 5.0 parts, 9.0 to 13.0% hydroxyl-containing polyvinyl Butiral (Butvar)^TMB76, Monsanto), 0.3 parts of trimethylolpropane; and 0.03 parts of 2-methyl-4,6-bis (trichloromethyl) -s-triazine (Bull. Chem. Soc. Japan, 42, 2924-). 2930 (1969)) is prepared. To this solution is added 0.01 part of the compound to be tested as a photosensitizer. The resulting solution is knife coated onto a 0.05 mm clean polyester film using a 0.05 mm knife orifice and the coating is air dried for about 30 minutes. A 0.05 mm clear polyester cover film is placed on the dry, but soft, tacky coating, taking care not to trap air as much as possible. The resulting sandwich structure is exposed to 161,000 Lux incident light for 3 minutes with light from a tungsten light source (FCHTM @ 650 Watt Quartz Iodine Lamp, General @ Electric) that provides light in both the visible and ultraviolet regions. . Exposure can be through a stencil to create exposed and unexposed areas of the structure. The exposure word, the film is removed, and the coating is treated with a finely divided colored powder, such as a color toner powder as commonly used in electrostatography. If the substance to be tested is a photosensitizer, the trimethylolpropane trimethacrylate monomer is exposed in the exposed area by photogenerated free radicals from 2-methyl-4,6-bis (trichloromethyl) -s-triazine. Polymerized. The polymerized areas are essentially non-sticky and the colored powder selectively adheres only to the sticky, non-exposed areas of the coating, essentially visible to the template Form an image.
[0083]
Preferably, the photosensitizer can also be selected in part with consideration of storage stability. Thus, the choice of a particular photosensitizer depends to some extent on the particular reactive species used (and the choice of electron donor compound and / or photoinitiator).
[0084]
Particularly preferred multiphoton photosensitizers include Rhodamine @ B (that is, N- [9- (2-carboxyphenyl) -6- (ditylamino) -3H-xanthan-3-ylidene] -N-ethylethanaminium. Large multiphotons, such as chloride, and the hexafluoroatsumonate salts of Rhordamine B) and four types of photosensitizers, such as those disclosed by Marder and Perry in International Patent Publications WO 98/21521 and WO 99/53242. And those showing an absorption cross section. These four types are as follows. (A) a molecule in which two donors are connected to a junction π (pi) electron bridge; and (b) a molecule in which two donors are replaced by one or more electron accepting groups. (C) a molecule in which two receptors are connected to a junction π (pi) electron bridge, and (d) a junction π (in which two receptors are replaced by one or more electron accepting groups. pi) molecules connected to an electronic bridge. (Here, “bridge” is a molecular fragment connecting two or more chemical groups, “donor” is a primitive or group having a low ionization potential capable of bonding to a junction π (pi) electron bridge, and “ "Acceptor" means an atom or group with high electron affinity, each capable of binding a junction π (pi) electron bridge).
[0085]
The following formula is given as a typical example of such a photosensitizer.
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[0086]
The four types of photosensitizers mentioned above react aldehydes with ylides under standard Wittig conditions or are described in International Patent No. It can be prepared using the McMurray reaction as detailed in WO 98/21521.
[0087]
Other compounds are described by Reinhardt et al. (Eg, in International Patent Nos. 6,100,405, 5,859,251 and 5,770,737) as having large multiphoton absorption cross-sections. Is measured in a different way than described above. Representative examples of compatible compounds are as follows.
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[0088]
Other compounds that may be used as photosensitizers in the present invention include fluorescin, p-bis (o-methylstyryl) benzene, eosin, rose bengal, erythrosine, coumarin 307 (Eastman @ Kodak), Cascade @ Blue @ hydrazine. Salt, Lucifer Yellow CH ammonium salt, 4,4-difluoro-1,3,5,7,8-pentamethyl-4-bora-3α, 4α-diazaindene-2,6-disulfonate, 1,1-dioctaldecyl- 3,3,3 ′, 3′-Tetramethylindocarbocyanine, Indo-1 pentapotassium salt (Molecular @ Probes), 5-diethylaminonaphthalene-1-sulfonylhydrazine, 4 ′, 6-diamidino-2-phenylindole・ Jihi Drochloride, 5,7-diiodo-3-butoxy-6-fluorone, 9-fluorone-2-carboxylic acid, and a compound having the following structure.
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[0089]
(2) Electron donor compound
Electron donor compounds useful within the multiphoton photoinitiator system of the photoreactive composition are those (except for the photosensitizer itself) that can provide electrons to the electronically excited state of the photosensitizer. . These electron donor compounds preferably have an oxidation potential greater than zero and less than that of p-dimethoxybenzene relative to a standard saturated calomel electrode. Preferably, the oxidation potential is between about 0.3 and 1 volt with respect to a standard saturated calomel electrode (SCE).
[0090]
Preferably, the electron donor compound is further soluble in the reactive species and is selected in part in view of storage stability (as described above). Suitable donors can generally increase the reaction rate (such as curing) or image density when exposed to light of the desired wavelength.
[0091]
When working with cationic reactive species, those skilled in the art will recognize that electron donor compounds can have a deleterious effect on cationic reactions if they are substantially basic. Will. (See, for example, US Pat. No. 6,025,406 (Oxman et al.), Column 7, line 62 to column 8, line 49).
[0092]
In general, electron donor compounds suitable for use with certain photosensitizers and photoinitiators (eg, as described in US Pat. No. 4,859,572 (Farid et al.)). ) Selection by comparing the oxidation-reduction potentials of the three components. Such potentials can be measured experimentally (eg, in the manner described in RJ Cox, Photographic Sensitivity, Chapter 15, Academic Press) (1973), or can be determined by the method described in N.W. L. Weinburg, Ed. , Technique \ of \ Electroorganic \ Synthesis \ part \ II \ Techniques \ of \ Chemistry, Vol. V (1975), and C.I. K, Mann @ and @ K. K. It is also shown in references such as Barnes, Electrochemical \ reactions \ in \ Noaqueous \ Systems (1970). This potential reflects the relative energy relationship and can be applied to electron donor compound selection in the following manner.
[0093]
When a photosensitizer is in an electronically excited state, the highest occupied molecular orbital (HOMO) of the photosensitizer is at a higher energy level (ie, the lowest unoccupied molecular orbital (LUMO) of the photosensitizer). , Leaving a void in the molecular orbital it originally occupied. The photoinitiator receives electrons from the higher energy orbitals, and when certain relative energy relationships are satisfied, the electron donor compound provides electrons to fill the gap in the first occupied orbital.
[0094]
If the reduction potential of the photoinitiator is more negative (or more positive) compared to the photosensitizer, electrons in the higher energy orbit of the photosensitizer will be It moves from the photosensitizer to the lowest unoccupied molecular orbital (LUMO) of the photoinitiator. If the process is somewhat bulbous (i.e., even though the photosensitizer's reduction potential is up to 0.1 volts more negative than that of the photoinitiator), the surrounding thermal activity will be less They easily get over the barrier.
[0095]
In a similar manner, if the oxidation potential of the electron donor compound is not positive (or more negative) compared to that of the photoinitiator, it moves from the soil HOMO to the orbital space of the photosensitizer. The moving electrons are moving from a higher potential to a lower potential, also indicating an exothermic process. Even if this process is somewhat endothermic (ie, the oxidation potential of the photosensitizer is more than 0.1 volts more positive than that of the electron donor compound), the peripheral thermal activation may be such a small barrier Is easily overcome.
[0096]
If the reduction potential of the photosensitizer is more than 0.1 volt negative compared to that of the photoinitiator, or the oxidation potential of the photosensitizer is not more than 0.1 volt compared to that of the electron donor compound. Mild endothermic reactions that are more positive than 1 volt occur at any instant, regardless of whether the photoinitiator or the electron donor compound first reacts with the photosensitizer in its excited state. When the photoreaction initiator or electron donor compound is reacting with the photosensitizer in its excited state, the reaction is preferably exothermic or somewhat endothermic. An exothermic reaction is also desirable when the photoinitiator or electron donor compound is reacting with the photosensitizer ion / radical, but it is still expected that more endothermic reactions will occur at many instants. Thus, the reduction potential of the photoinitiator may be up to 0.2 volts (or more) negative compared to that of the second reacting photoinitiator, or the oxidation potential of the photosensitizer. May be up to 0.2 volts (or more) positive compared to that of the second reacting electron donor compound.
[0097]
Suitable electron donor compounds include, for example, F. Faton is an Advances in Photochemistry, edited by B.B. Voman @ et @ al. , Volume 13, pp. 427-488, John Wiley and Sons, New York (1986), or Oxmann et al. At column 7, lines 42-61 of US Pat. No. 6,025,406, and Palazzottoto et al. At US Pat. No. 676, column 4, line 14 to column 5, line 18. Such electron donor compounds include (triethanolamine, hydrazine, 1,4-diazabicyclo [2,2,2] octane, triphenolamine (and its triphenylphosphine and triphenylarsine analogs, aminoaldehydes, and aminosilanes). Amines (including phosphoramides), amides (including phosphoramides), ethers (including thioethers), sulfuric acid and its salts, phenocyanide salts, ascorbic acid and its salts, xanthan salts, ethylenediaminetetraacetic acid, (alkyl ) N (allyl) n borate (n + m = 4) (preferably tetraalkylammonium salt), SnR4 compound (each R is selected from the group consisting of alkyl, aralkyl (particularly benzyl), allyl, and alkaryl groups) Various organometallic compounds (eg, n-C₃H₇Sn (CH₃)₃, (Allyl) Sn (CH₃)₃, And (benzyl) Sn (n-C₃H₇)₃Etc.), ferrosin and the like, and mixtures thereof. The electron donor compound may be unsubstituted or substituted with one or more non-interfering substituents. Particularly preferred electron donor compounds contain an electron donor atom (such as a nitrogen, oxygen, phosphorus, and sulfur atom) and an extractable hydrogen atom bonded to a carbon or silicon atom in addition to the electron donor atom.
[0098]
Preferred amine electron donor compounds include alkyl-, allyl-, alkaryl-, and aralkyl-amines (e.g., methylamine, ethylamine, propylamine, butylamine, triethanolamine, amylamine, 2,4-dimethylaniline, 3-dimethylaniline, o-, m-, and p-toluidine, benzylamine, aminopyridine, N, N'-dimethylethylenediamine, N, N'-diethylethyldiamine, N, N'-dibenzylethylenediamine, N, N′-diethyl-1,3-propanediamine, N, N′-diethyl-2-butene-1,4-diamine, N, N′-dimethyl-1,6-hexanediamine, piperazine, 4,4′- Trimethylene dipiperazine, 4,4'-ethylene dipiperazine, p-N, N-dimethyl- Aminofentanol, and pN, N-dimethylaminobenzonitrile); aminoaldehydes (e.g., pN, N-dimethylaminobenzaldehyde, pN, N-diethylaminobenzaldehyde, 9-julolidine, and 4-morphoinbenzaldehyde) And aminosilanes (eg, triethylsilylmorpholine, trimethylsilylpiperidine, bis (dimethylamino) diphenylsilane, tris (dimethylamino) methylsilane, N, N-diethylaminotrimethylsilane, tris (dimethylamino) phenylsilane, tris (methylsilyl) amine , Bis (dimethylsilyl) amine, N, N-bis (dimethylsilyl) aniline, N-phenyl-N-dimethylsilylaniline, and N, N-dimethyl-N-di Chill silyl amine); and mixtures thereof. Tertiary aromatic alkylamines, especially those having at least one electron withdrawing group on the aromatic tube, have been found to have particularly good storage stability. Excellent storage stability can also be obtained using amines that are solid at room temperature. Excellent photographic speed has been obtained with amines containing one or more judurinyl moieties.
[0099]
Preferred amine electron donor compounds include N, N-dimethylacetamine, N, N-diethylacetamine, N-methyl-N-phenylacetamine, hexamethylphosphoramine, hexaethylphosphoramine, hexapropylphosphoramine, Trimorpholine phosphine oxide, tripiperazino phosphine oxide, and mixtures thereof.
[0100]
Preferred alkylallyl borate salts include:
Ar₃B⁻(N-C₄H₉) N⁺(C₂H₅)₄
Ar₃B⁻(N-C₄H₉) N⁺(CH₃)₄
Ar₃B⁻(N-C₄H₉) N⁺(N-C₄H₉)₄
Ar₃B⁻(N-C₄H₉) Li⁺
Ar₃B⁻(N-C₄H₉) N⁺(C₆H_Thirteen)₄
Ar₃B⁻(C₄H₉) N⁺(CH₃)₃(CH₂)₂CO₂(CH₂) CH₃Ar₃B⁻(C₄H₉) N⁺(CH₃)₃(CH₂)₂OCO (CH₂)₂CH₃
Ar₃B⁻(Sec-C₄H₉) N⁺(CH₃)₃(CH₂)₂CO₂(CH₂) CH₃
Ar₃B⁻(Sec-C₄H₉) N⁺(C₆H_Thirteen)₄
Ar₃B⁻(C₄H₉) N⁺(C₈H₁₇)₄
Ar₃B⁻(C₄H₉) N⁺(CH₃)₄
(P-CH₃OC₆H₄)₃B⁻(N-C₄H₉) N⁺(N-C₄H₉)₄
Ar₃B⁻(C₄H₉) N⁺(CH₃)₃(CH₂)₂OH
ArB⁻(N-C₄H₉)₃N⁺(CH₃)₄
ArB⁻(C₂H₅)₃N⁺(CH₃)₄
Ar₂B⁻(N-C₄H₉)₂N⁺(CH₃)₄
Ar₃B⁻(C₄H₉) N⁺(C₄H₉)₄
Ar₄B⁻N⁺(C₄H₉)₄
ArB⁻(CH₃)₃N⁺(CH₃)₄
(N-C₄H₉)₄B⁻N⁺(CH₃)₄
Ar₃B⁻(C₄H₉) P⁺(C₄H₉)₄
(Where Ar is phenyl, naphthyl, substituted (preferably fluoro substituted) phenyl, substituted naphthyl, and similar groups with more fused aromatic rings), and tetramethylammonium n-butyltriphenylborate and tetrabutylammonium n-Hexyl-tris (3-fluorophenyl) borate (commercially available from Ciba Specialty Chemicals Corporation as CGI 437 and CGI 746), and mixtures thereof.
[0101]
Suitable ether electron donor compounds are 4,4'-dimethoxybiphenyl, 1,2,4-triethoxybenzene, 1,2,4,5-tetramethoxybenzene, and the like, and mixtures thereof. Suitable urea electron donor compounds are N, N'-dimethylurea, N, N-dimethylurea, N, N'-diphenylurea, tetramethylthiourea, tetraethylthiourea, tetra-n-butylthiourea, N, N-diurea -N-butylthiourea, N, N'-di-n-butylthiourea, N, N-diphenylthiourea, N, N'-diphenyl-N, N'-diethylthiourea and the like, and mixtures thereof.
[0102]
Preferred electron donor compounds for free radical inducing reactions include amines, including one or more julolidinyl moieties, alkyl borate salts, and aromatic sulfates. However, if desired (eg, to improve the storage stability of the photoreactive composition or to modify resolution, contrast, and reciprocity), such an electron donor compound may be used for such a reaction. In some cases, there is no need to do so. Preferred electron donor compounds for the acid-induced reaction include 4-dimethylaminobenzoic acid, ethyl-4-dimethylaminobenzoate, 3-dimethylaminobenzoic acid, 4-dimethylaminobenzoin, 4-dimethylaminobenzaldehyde, 4-dimethyl Aminobenzonitrile, 4-dimethylaminophenethyl alcohol, and 1,2,4-trimethoxybenzene.
[0103]
(3) Photoreaction initiator
Suitable photoinitiators of the reactive species of the photoreactive composition can be photosensitized by accepting electrons from a remote photosensitizer in an electronically excited state, at least free radicals and / or acids Leads to the formation of Such photoinitiators include iodonium salts (eg, diallyliodonium salts), chloromethylated triazines (eg, 2-methyl-4,6-bis (trichloromethyl) -s-triazine, 2,4,6- tris (trichloromethyl) -s-triazine, and 2-allyl-4,6-bis (trichloromethyl) -s-triazine), diazonium salts (eg, optionally substituted with groups such as alkyl, alkoxy, halo, or nitro) Phenyldiazonium salts), sulfonium salts (e.g., triallylsulfonium optionally substituted with an alkyl or alkoxy group and optionally a 2,2'-oxy group triallylsulfonium salt bridging an adjacent allylic moiety) , Azinium salts (eg, N-alkoxypyridinium), and Allyl imidazolyl dimers (preferably 2,4, such as 2,2 ′, 4,4 ′, 5,5′-tetraphenyl-1′1′-biimidazole optionally substituted by alkyl, alkoxy, or halo) 5-triphenylimidazoyl dimer), and the like, and mixtures thereof.
[0104]
The photoinitiator is preferably soluble in the reactive species and preferably has excellent storage stability (ie, the reactive species when dissolved in the presence of the photosensitizer and the electron donor compound). Does not spontaneously promote the reaction). Thus, the choice of a particular photoinitiator will depend in part on the particular reactant, photosensitizer, and electron donor compound as described above. Preferred photoinitiators have large multiphoton absorption cross-sections as described by Marder, Perry et al. In PCT patent applications WO 98/21521 and WO 99/3324, and by Goodman et al. In PCT patent application WO 99/54784. Things.
[0105]
Suitable iodonium salts include those described by Palazzotto et al. In U.S. Pat. No. 5,545,676, column 2, lines 28-46. Suitable iodonium salts are described in U.S. Pat. Nos. 3,729,313, 3,741,769, 3,808,006, 4,250,053 and 4,394,403. It is stated in. Iodonium salts are simple salts (eg, Cl 2⁻, Br⁻, I⁻Or C₄H₅SO₃ ⁻) Or metal complex salts (eg, SbF₆ ⁻, PF₆ ⁻, BF₄ ⁻, Tetrakis (perfluorophenyl) borate, SbF₅OH⁻Or AsF₆ ⁻). Mixtures of iodonium salts can also be used if desired.
[0106]
Examples of useful aromatic iodonium complex salt photoinitiators include diphenyliodonium tetrafluoroborate; di (4-methylphenyl) iodonium tetrafluoroborate; phenyl-4-methylphenyliodonium totrafluoroborate; di ( 4- (heptylphenyl) iodonium tetrafluoroborate; di (3-nitrophenyl) iodonium hexafluorophosphate; di (4-chlorophenyl) iodonium hexafluorophosphate; di (naphthyl) iodonium tetrafluoroborate, di (4- Trifluoromethylphenyl) iodonium tetrafluoroborate; diphenyliodonium hexafluorophosphate; di (4-methylphenyl) iodonium hexafluorophosphate G; diphenyliodonium hexafluoroarsenate; di (4-phenoxyphenyl) iodonium tetrafluoroborate; phenyl-2-thionyliodonium hexafluorophosphate; 3,5-dimethylpyrazolyl-4-phenyliodonium hexafluorophosphate; Diphenyliodonium hexafluoroantimonate; 2,2'-diphenyliodonium tetrafluoroborate; di (2,4-dichlorophenyl) ioni hexafluorophosphate; di (4-bromophenyl) iodonium hexafluorophosphate; di (4 -Methoxyphenyl) ioni hexafluorophosphate; di (3-carboxyphenyl) iodonium hexafluorophosphate; di (3-oxycarbonyl Phenyl) iodonium hexafluorophosphate; di (3-methoxysulfonylphenyl) iodonium hexafluorophosphate; di (4-acetamidophenyl) iodonium hexafluorophosphate; di (2-benzothienyl) iodonium hexafluorophosphate; and diphenyl Iodonium hexafluoroantimonate and the like, and mixtures thereof. Aromatic iodonium complex salts are described in Beringeret. al. , J. et al. Am. Chem. Soc. , 81, 342 (1959) (eg, by conversion of diphenyliodonium bisulfate).
[0107]
Preferred iodonium salts are diphenyliodonium (diphenyliodonium chloride, diphenyliodonium hexafluorophosphate, and diphenyliodonium tetrafluoroborate), diallyliodonium hexafluorophoantimonate (e.g., SarCat available from Sartometer @ Company).^TMSR # 1012), and mixtures thereof.
[0108]
Useful dichloromethylated triazines include those described in U.S. Pat. No. 3,779,778 (Smith et al.), Column 8, lines 45-50, which includes 2,4-bis (trichloromethyl)- 6-methyl-s-triazine, 2,4,6-tris (trichloroethyl) -s-triazine, and are disclosed in U.S. Patent Nos. 3,987,037 and 3,954,475 (Bonham et al.). And more preferred chromophore-substituted vinylhalomethyl-s-thrazine and the like.
[0109]
Useful diazonium salts include those described in U.S. Pat. No. 4,394,433 (gatzke et al.), Which includes an external diazonium group (-N⁺= N) and those containing a photosensitive aromatic moiety having an anion (eg, chlorine, tri-isopropyl naphthalene sulfonate, tetrafluoroborate, and bis (perfluoroalkylsulfonyl) methide, and the like). Examples of useful diazoniums include 1-diazo-4-anilylobenzene, N- (4-diazo-2,4-dimethoxyphenyl) pyrrolidine, 1-diazo-2,4-diethoxy-4-morpholinobenzene, 1 -Diazo-4-benzoylamino-2,5-diethoxybenzene, 4-diazo-2,5-dibutoxyphenyl morpholino, 4-diazo-1-dimethylaniline, 1-diazo-N, N-dimethylaniline , 1-diazo-4-N-methyl-N-hydroxyethylaniline and the like.
[0110]
Useful sulfonium salts are described in US Pat. No. 4,250,053 (Smith), column 1, line 66 to column 4, line 2, and have the following formula:
Embedded image

Represented by R₁, R₂, And R₃Is an aromatic group having about 4 to about 20 carbon atoms (eg, substituted or unsubstituted phenyl, naphthyl, thienyl, furanyl, etc., and the substituents are alkoxy, alkylthio, allylthio, halogen, etc.) and carbon It is selected from the group consisting of alkyl groups having 1 to about 20 atoms. As used herein, “alkyl” includes substituted alkyl (eg, substituted with halogen, alkoxy, or allyl) and the like. R₁, R₂, And R₃At least one is aromatic, and preferably each is independently aromatic. Z is a covalent bond, oxygen, sulfur, -S (= O)-, -C (= O)-,-(O =) S (= O)-, and -N (R)-, and R is ( Allyl having about 6 to 20 carbon atoms such as phenyl, allyl (having about 2 to about 20 carbon atoms such as acetyl and benzoyl), a carbon-carbon bond,_4-) C (-R₅)-And R₄And R₅Is selected from the group consisting of hydrogen, an alkyl group having 1 to about 4 carbon atoms, and an alkenyl group having about 2 to about 4 carbon atoms;⁻Is as described below.
[0111]
Suitable anions for sulfonium (and other types of photoinitiators), X⁻Include various anions such as, for example, cations centered on imide, methide, boron, phosphorus, antimony, arsenic, and aluminum.
[0112]
Suitable imide and methide anions are (C₂F₅SO₂)₂N⁻, (C₄F₉SO₂)₂N⁻, (C₈F₁₇SO₂)₃C⁻, (CF₃SO₂)₃C⁻, (CF₃SO₂)₂N⁻, (C₄F₉SO₂)₃C⁻, (CF₃SO₂)₂(C₄F₉SO₂) C⁻, (CF₃SO₂) (C₄F₉SO₂)₂N⁻, ((CF₃)₂NC₂F₄SO₂)₂N⁻, (CF₃)₂NC₂F₄SO₂C⁻(SO₂CF₃)₂, (3,5-bis (CF₃) C₆H₃) SO₂N⁻SO₂CF₃, C₆H₅SO₂C⁻(SO₂CF₃)₂, C₆H₅SO₂N⁻SO₂CF₃And so on. In this type of shade (R_fSO₂)₃C-, where R_fIs a perfluoroalkyl radical having 1 to about 4 carbon atoms.
[0113]
Suitable boron center anions include F₄B-, (3,5-bis (CF₃) C₆H₃)₄B⁻, (C₆F₅)₄B⁻, (P-CF₃C₆H₄)₄B⁻, (M-CF₃C₆H₄)₄B⁻, (P-FC₆H₄)₄B⁻, (C₆F₅)₃(CH₃) B⁻, (C₆F₅)₃(N-C₄H₉) B⁻, (P-CH₃C₆H₄)₃(C₆F₅) B⁻, (C₆F₅)₃FB⁻, (C₆H₅)₃(C₆F₅) B⁻, (CH₃)₂(P-CF₃C₆H₄)₂B⁻, (C₆F₅)₃(N-C₁₈H₃₇O) B⁻And so on. Preferred boron-centered anions usually have three or more halogen-substituted aromatic hydrocarbon radicals attached to boron, with the most preferred halogen being fluorine. A preferred anion is (3,5-bis (CF₃) C₆H₃)₄B⁻, (C₆F₅)₄B⁻, (C₆F₅)₃(N-C₆H₉) B⁻, (C₆F₅)₃FB⁻And (C₆F₅)₃(CH₃) B⁻And so on.
[0114]
Suitable anions containing other metals include, for example, (3,5-bis (CF₃) C₆H₃)₄Al⁻, (C₆F₅)₄Al⁻, (C₆F₅)₂F₄P⁻, (C₆F₅) F₅P⁻, F₆P⁻, (C₆F₅) F₅Sb⁻, F₆Sb⁻, (HO) F₅Sb⁻, And F6As⁻. The above list is not exhaustive and other useful boron-centered non-nucleophilic salts and other useful anions containing metals and non-metals (from the general formula shown above) It will be apparent to those skilled in the art.
[0115]
Preferably, the anion X⁻Is selected from the group consisting of tetrafluoroborate, hexafluorophosphate, hexafluoroarsenate, hexafluoroantimonate, and hydroxypentafluoroantimonate (eg, for use with a cationic reactive species such as an epoxy resin).
[0116]
Suitable sulfonium salt photoinitiators include:
Triphenylsulfonium,
Methyldiphenylsulfonium tetrafluoroborate
Dimethylphenylsulfonium hexafluorophosphate
Triphenylsulfonium hexafluorophosphate
Triphenylsulfonium hexafluoroantimonate
Diphenylnaphthylsulfonium hexafluoroarsenate
Tritolsulfonium hexafluorophosphate
Anisyldiphenylsulfonium hexafluoroantimonate
4-butoxyphenyldiphenylsulfonium tetrafluoroborate
4-chlorophenyldiphenylsulfonium hexafluorophosphate
Tri (4-phenoxyphenyl) sulfonium hexafluorophosphate
Di (4-ethoxyphenyl) methylsulfonium hexafluoroarsenate
4-acetonylphenyldiphenylsulfonium tetrafluoroborate
4-thiomethoxyphenyldiphenylsulfonium hexafluorophosphate
Di (methoxysulfonylphenyl) methylsulfonium hexafluoroantimonate,
Di (nitrophenyl) phenylsulfonium hexafluoroantimonate
Di (carbomethoxyphenyl) methylsulfonium hexafluorophosphate,
4-acetamidophenyldiphenylsulfonium tetrafluoroborate,
Dimethylnaphthylsulfonium hexafluorophosphate,
Trifluoromethyldiphenylsulfoniumtetrafluoroborate,
p- (Phenylthiophenyl) diphenylnylsulfonium hexafluoroantimonate
10-methylphenoxaasinium hexafluorophosphate
5-methylthianthenium hexafluorophosphate
10-phenyl-9,9-dimethylthioxane hexafluorophosphate
10-phenyl-9-oxothioxanthenium tetrafluoroborate
5-methyl-10-oxothiantrenium tetrafluoroborate
5-methyl-10,10-dioxothianthenium hexafluorophosphate
And so on.
[0117]
Preferred sulfonium salts are triallylsulfonium hexafluoroantimonate (eg, SarCat, commercially available from Sartomer Company).^TMSR1010), triallylsulfonium hexafluorophosphate (for example, SarCat commercially available from Sartomer @ Company)^TMSR1011), and triallylsulfonium hexafluoroantimonium (for example, SarCat commercially available from Sartomer Company)^TMK185).
[0118]
Useful azinium salts include those disclosed in U.S. Pat. No. 4,859,572 (Fraid et al.), Column 8, line 51 to column 9, line 46, including pyridinium, diazinium, or triazinium. Components. The azinium moiety comprises one or more aromatic rings, usually carbocyclic aromatic rings (eg, quinolinium, isoquinolylium, benzodiazinium, and naphthodiazonium components), which are fused to the azinium ring. I have. When electron transfer to the azinium photoinitiator of the photosensitizer occurs when the quaternizing substituent of the nitrogen atom in the azinium ring is electronically excited, it is released as a free radical. In one preferred form, the quaternizing substituent is an oxy substituent. The oxy substituents that quaternize the ring nitrogen atom of azinium, -O and -T, can be selected from a variety of synthetic oxy substituents. The constituent part T is, for example, an alkyl radical such as methyl, ethyl, or butyl. The alkyl radical may be substituted. For example, aralkyl (eg, benzyl and phenethyl and the like) and sulfoalkyl (eg, sulfomethyl) radicals may be useful. In another aspect, T is, for example, -OC (O) -T¹Is a radical, where T can be any of the various alkyl and aralkyl radicals described above. Furthermore, T¹May be any radical such as phenyl or naphthyl. Allyl radicals may be substituted. For example, T¹May be a tolyl or xylyl radical. T usually contains from 1 to about 18 carbon atoms. The alkyl moiety in each example is preferably a lower alkyl moiety, and the allyl moiety in each example preferably contains from about 6 to about 10 carbon atoms. The highest activity levels are achieved when the oxy substituents -O, -T contain one or two carbon atoms. The azinium nucleus must contain no substituents other than the quaternizing substituent. However, the presence of other substituents is not absolutely necessary for the activity of these photoinitiators.
[0119]
Useful triallylimidazoyl dimers are those described in U.S. Pat. No. 4,963,471 (Trout et al.), Column 8, lines 18-28. These dimers include, for example, 2- (o-chlorophenyl) -4,5-bis (m-methoxyphenyl) -1,1′-bimidazole; 2,2′-bis (0-chlorophenyl) -4,4 ′ 5,5′-tetraphenyl-1,1′-bimidazole; and 2,2′-bis (o-chlorophenyl) -4,4 ′, 5,5′-tetraphenyl-1,1′-bimidazole; and , 2,5-bis (o-chlorophenyl) -4- [3,4-dimethoxyphenyl] -1,1'-bimidazole and the like.
[0120]
Preferred photoinitiators include iodonium salts (more preferably, 2,4,5-triphenylimidazolyl dimer), sulfonium salts, and diazonium salts. More preferred are allyliodonium salts, chloromethylated triazines, and 2,4,5-triphenylimidazolyl dimers (allyliodonium and triazine are most preferred).
[0121]
Preparation of photoreactive composition
Reactive species, multiphoton photosensitizers, electron donor compounds, and photoinitiators can also be prepared by the methods described above, or by other methods of the prior art, many of which are commercially available. These four components can be combined in any combination order and manner (optionally with stirring) under "safe light" conditions, but the photoinitiator is added last (and dissolution of the other components It is preferred to add (after a heating step optionally used to accelerate) (in terms of shelf life and thermal stability). A solvent can be used if necessary, but the solvent must be chosen so that it does not significantly react with the components of the composition. Suitable solvents include, for example, dichloromethane, and acetonitrile. In some cases, the reactive species itself may function as a solvent for other components.
[0122]
The components of the photoinitiator system are present in a photochemically effective amount (as described above). Generally, the composition contains at least about 5%, preferably at least about 10%, and more preferably at least about 20%, by weight, of one or more reactive species. Generally, the composition will contain up to 99.79%, preferably about 95%, and more preferably up to about 80%, by weight, of one or more reactive species. Generally, the composition will comprise at least about 0.01%, preferably about 0.1%, more preferably at least about 0.2%, of one or more photosensitizers, based on the weight of one or more reactive species. Contains sensitizers. Generally, the compositions will contain about 10%, preferably up to about 5%, and more preferably up to about 2%, by weight, of one or more photosensitizers. Preferably, the composition contains at least about 0.1% by weight of the electron donor. Preferably, the composition contains about 10%, and preferably about 5%, by weight, of one or more electron donors. Preferably, the composition comprises about 0.1% by weight of one or more photoinitiators. Preferably, the composition contains up to about 10% by weight, and preferably up to about 5%, of one or more photoinitiators. When the reactive species is a leuco dye, the composition will usually comprise at least about 0.01%, preferably at least about 0.3%, more preferably at least about 1%, and most preferably at least about 2% by weight. It has one or more leuco dyes. When the reactive species is a leuco dye, the composition typically includes up to about 10% by weight of the leuco dye. These proportions are not solutions, but are on a solid basis, i.e., based on the total weight of the components.
[0123]
Numerous adjuvants can be included depending on the desired end use form. Suitable auxiliaries are solvents, diluents, resins, binders, plasticizers, contents, dyes, inorganic or organic reinforcements or stretching fillers (preferably about 10 to 90% by weight of the total weight of the composition), Thixotropic agents, indicators, reaction inhibitors, stabilizers, ultraviolet absorbers, drugs (eg, leachable fluoride), and the like. The amounts and types of such adjuvants and how to add them to the composition are well known to those skilled in the art.
[0124]
For example, it is within the scope of this invention to include a non-reactive polymeric binder in the composition to control tack and provide film forming properties. Such polymeric binders are usually selected on the basis of compatibility with the reactive species. For example, a polymeric binder that is soluble in the same solvent used for the reactive species and does not contain a functional group that adversely affects the course of the reaction of the reactive species can be used. The binder may be of a suitable molecular weight to achieve the desired film-forming properties and solution rheology (e.g., in the range of about 5,000 to 1,000,000 daltons, preferably about 10,000 to 500,000 daltons, more preferably (Ranging from about 15,000 to 250,000 daltons). Suitable polymeric binders include, for example, polystyrene, poly (methyl methacrylate), poly (styrene) -co- (acrylonitrile), cellulose acetate butyrate, and the like.
[0125]
Prior to exposure, the resulting photoreactive composition is, if necessary, applied to a substrate by various coating methods known to those skilled in the art (including, for example, knife coating and spin coating, etc.). Can be coated. The substrate can be selected from a variety of substrates, such as films, sheets, and other surfaces, based on the particular purpose of use and the exposure method used. Preferred substrates usually have sufficient planarity to create a layer of the photoreactive composition having a uniform thickness. For applications where less coating is required, the photoreactive composition can be exposed in bulk form.
[0126]
Exposure system and its use
Useful exposure systems have at least one light source (usually a pulsed laser) and at least one optical element. A suitable light source is, for example, a femtosecond near-infrared titanium sapphire oscillator (eg, Coherent Mira Optima 900-F) pumped with an argon ion laser (eg, Coherent \ Innova). Operating at 76 MHz, this laser has a pulse width of 200 femtoseconds, is tunable in the range of 700-980 nm, and has an average power of up to 1.4 watts. However, in practice, any light source that provides sufficient intensity (to induce multiphoton absorption) at a wavelength suitable for the photosensitizer (used in the photoreactive composition) can be used. Such wavelengths typically range from about 300 nm to about 1500 nm, preferably from about 600 nm to about 1100 nm, more preferably from about 750 nm to about 850 nm. Peak intensity is usually at least about 10⁶W / cm²It is about. The upper limit of pulse fluence (energy per pulse per unit area) is usually dictated by its photoreactive depletion threshold. For example, a Q-switched Nd: YAG laser (e.g., Spectra-Physics @ Quanta-Ray @ PRO), a visible light dye laser (e.g., Spectra-Physics@Q.RTM. Pumped with Spectra-Physics @ Quanta-Ray @ PRO, and a Q-switch with a Sirah diode). Pump laser (for example, Spectra-Physics @ FCcar)^TM) Can also be used. A preferred light source is a near infrared laser with a pulse length of less than about 10 nanoseconds (more preferably, less than about 1 nanosecond, and most preferably, less than about 10 picoseconds). Other pulse lengths may be used as long as the peak intensity and fluence described above are satisfied.
[0127]
Optical elements useful in performing the method of the present invention include refractive optics (eg, lenses and prisms), reflective optics (eg, retroreflectors, or collecting mirrors), diffractive optics (eg, Gratings, phase masks, and holograms), dispersing devices, Pocket cells, waveguides, wave plates, birefringent liquid crystals, and the like. Such optics are useful for purposes such as focusing, beam transmission, beam / mode shaping, pulse shaping, and pulse timing. Usually, combinations of optical elements are used, and those skilled in the art will readily recognize other combinations. It is often desirable to use an optical device having a large numerical aperture to provide highly concentrated light. However, any combination of optical elements that provide the desired intensity characteristics (and their spatial arrangement) can be used. For example, the exposure system can use a scanning confocal microscope (BioRad MRC600) with a 0.75 NA objective (Zeiss 20X Fluar).
[0128]
Typically, exposure of the photoreactive composition is performed by using a light source (as described above) with optical elements as a means for controlling the three-dimensional spatial distribution of light intensity within the composition. For example, light from the pulsed data is passed through a collection lens such that its focal point is within the volume of the composition. The focal point can be scanned or moved according to a three-dimensional pattern corresponding to the desired shape, thereby creating the desired shape. The volume of the composition that can be exposed or illuminated can be either by moving the composition itself or by moving a light source (eg, by moving a laser beam using a galvo mirror). Can be scanned.
[0129]
If the light triggers a reaction that produces, for example, a substance having a solubility property different from that of the reactive species, the resulting image is optionally rendered using, for example, a suitable solvent, or using other well-known methods. It is developed by removing exposed or unexposed areas. In this way, complex, three-dimensional objects can be created.
[0130]
Exposure time is typically determined by the type of exposure system used for imaging (and numerical aperture, light intensity spatial distribution, peak light intensity in the laser pulse (higher and shorter pulse durations are more or less And the nature of the composition to be exposed (and the concentration of photosensitizer, photoinitiator, and electron donor compound). In general, the higher the peak light intensity in the focal region, the shorter the exposure time, even if other parameters are the same. Linear imaging or "writing" speeds are typically 10^-8-10^-15Seconds (preferably about 10^-11-10^-14Seconds) laser pulse duration, and 10 per second²-10⁹Pulse (preferably about 10³-10⁸About 5 to 100,000 microns / sec.
[0131]
Example
The objects and advantages of the present invention will be further described with reference to the following examples, but the specific substances and amounts described in these examples, and other conditions and details, limit the scope of the present invention. It does not do. These examples describe the use of optical elements to create a three-dimensional shape in a photoreactive composition.
[0132]
Example 1
This embodiment discusses a phase or diffractive mask for forming a photopolymerized region by a multiphoton absorption process.
[0133]
An input beam having a uniform energy distribution is used to calculate the phase profile of the diffraction mask. In this embodiment, a simple square grid of lines, all located on one plane, serves as the test pattern to reduce the time required for calculations. Fabrication of the mask is performed through conventional etching techniques, which have four phase levels to provide diffraction efficiency.
[0134]
The phase mask design creates a series of focal points or lines in one plane, with a focal length of 10 millimeters (mm) and an effective numerical aperture of 0.50. The series of focal lines generated by the mask form a square grid with a line spacing of 0.5 centimeters (cm) in the x or y direction. The writing laser is an enhanced Ti: Sapphire laser that provides 750 milliwatts (mW) at 800 nanometers (nm) at 1 kilohertz (kHz) and a pulse width of 120 femtoseconds (fs). TEM from laser₀₀The output enters an optical system that converts the input Gaussian beam into a uniform energy distribution having a rectangular cross section of 0.1 cm x 10.1 cm. The fluence per pulse in the plane of the phase mask is 0.74 millijoules per square centimeter (mJ / cm²). The phase mask is attached to a holding stop that vertically separates the bottom of the mask from the sample surface by about 9.5 mm. A fine adjustment of the mask mounting matches the final focus position to the top surface of the sample. The mask mount and the sample stage move with respect to each other with an alignment accuracy. The rectangular beam from the laser strikes perpendicular to the mask plane and the long axis of the beam is parallel to the short axis of the mask. The laser beam is stationary with respect to the stage and mask movement.
[0135]
A test sample consisting of a polished glass wafer having a thickness of 8 mm, a diameter of 12.7 cm and an average surface roughness of 0.1 micrometer (μm) provides the basis for the polymer coating. The multi-photon initiator 4,4'-bis (diphenylamino) -trans-stilbene was coated on the polished side of the glass wafer with a thin layer of methyl nethacrylate monomer loaded at 1%. . The composition of this polymerizable coating consists of 40% tris- (2-hydroxyethylene) isocyanate triacrylate ester, 59% methyl methacrylate, and 1% of the solid component of a multiphoton adsorbent, and 40% by weight of dioxane in dioxane. Dissolved. This layer of polymerizable material is approximately 100 μm thick. Exposure of the polymerizable coating on the coated glassware is performed by moving the phase mask and sample structure continuously along a direction parallel to the short axis of the rectangular beam emerging from the optical system. Is The sample stage moves at a uniform speed of 100 μm / sec. As the light source scans the phase mask, the grid of lines is photopolymerized in the polymerizable layer.
[0136]
When the PMMA coating is developed in dioxane, unreacted areas are removed from the glass wafer and reacted (eg, photocured) lines appear in the form of a square grid. The individual lines forming the grid have a thickness of about 20 μm and a width of about 15 μm. This polymeric line has excellent adhesion to glass wafers.
[0137]
Examples 2 to 6
In these embodiments, various different arrays of optical element arrays are used to create multiple regions of material that have been at least partially reacted by multiphoton photopolymerization in a single exposure path. Unless otherwise noted, Aldrich Chemical Co. , Milwaukee, Wis., Was used.
[0138]
A two-photon photosensitive dye, Bis- [4- (diphenylamino) styryl] -1,4- (dimethoxy) benzene, was made by the following procedure. (1) Reaction of 1,4-bis-bromomethyl-2,5-dimethoxybenzene with triethyl phosphate (Horner Eamon's reagent); 1,4-bis-bromomethyl-2,5-dimethoxybenzene is described in the literature (Syper et al. , Tetrahedron, 1983; 39, 781-792). 1,4-bis-bromomethyl-2,5-dimethoxybenzene (253 g, 0.78 mol) was placed in a 1000 mL round bottom flask. Triethyl phosphate (300 g, 2.10 mol) was added. The reactants were heated with stirring under a nitrogen atmosphere for 48 hours. The reaction mixture is cooled and excess P (OEt)₃Was removed in vacuo using a Kugelrohr apparatus. The desired product was not actually distilled but excess P (OEt) was detected using the Kugelrohr apparatus.₃Was removed by distillation from the product. When heated to 100 ° C. at 0.1 mmHg, a clear oil was obtained. Upon cooling, the desired product was obtained as a solid. This product is suitable for direct use in the next step,¹1 H NMR showed agreement with the proposed structure. Recrystallization from toluene gave colorless needle-like crystals, which resulted in a purer product, which was not needed in most cases for the next step.
[0139]
(2) Synthesis of Bis- [4- (diphenylamino) styryl] -1,4- (dimethoxy) benzene: A calibrated dropping funnel and a magnetic stirrer were attached to a 1000 mL round bottom flask. To this flask was added the product from the above synthesis (Hormer @ Eamons reagent) (19.8 g, 45.2 mol) and N, N-dimethylamino-p-benzaldehyde (Fluka, 25 g, 91.5 mol). Mmol) were also added. The flask was flushed with nitrogen and sealed with a septum. Anhydrous tetrahydrofuran (750 mL) was injected into the flask to dissolve all solid components. KOtBu (potassium t-broxide) (125 mL, 1.0 M dissolved in THF) was added to the dropping funnel. The solution in the flask was stirred, and the KOtBu solution was added to the contents in the flask over 30 minutes. The solution was kept stirring overnight at ambient temperature. This reaction is then₂O (500 mL) was added and the mixture was quenched. The reaction was kept stirring, and after about 30 minutes a highly fluorescent yellow solid formed in the flask. This solid was separated by filtration and dried with air. And it was recrystallized with toluene (450 mL). The desired product was obtained as fluorescent needles (24.7 g, 81% yield).¹HRM was consistent with the proposed structure.
[0140]
The light source for Examples 2-5 was a diode-pumped Ti: Sapphire laser (Spectra-Physics) at a wavelength of 800 nm, a pulse width of about 100 fs, a pulse repetition rate of 80 MHz, a beam diameter of about 2 mm, and an average The output power was 860 mW. The optical system consisted of a low dispersion rotating mirror and an optical attenuator for changing the light output. The final light-collecting element has been described in detail in each embodiment. The movement of the sample, or the sample and the final light collection element, is described in New England, Affiliated, Technologies, Inc. (Lawrence, MA) using a motorized computer controlled stage.
[0141]
[Table 1]

[0142]
Example 2
In Example 2, the collimated beam was split into multiple focused spots in the sample volume using an array of fused silica microlenses (commercially available from MEMS Optical of Huntsville, AL). The microlenses were configured in a hexagonal array, and the filling ratio was 70%. Each microlens was 76 microns in diameter and 0.5 numerical aperture. With these test substrates, the reaction (e.g., photocuring) is performed by placing the lens array over the 70 [mu] m shim on top of the substrate so that the focal position of each microlens is approximately coincident with the substrate / polymer interface. (See FIG. 1a).
[0143]
Test samples were pretreated with a 2% solution of trimethoxysilylpropyl methacrylate in aqueous ethanol as an adhesion promoter, after which photoreactive composition I (Table 1) was treated with dioxane (Mallinckordt Baker Co., Inc., Phillipsburg, A glass microscope slide which was spin-coated with a 46% solution of the solid component dissolved in NJ) was used. The coated slide was heat treated in a furnace at a temperature of 80 ° C. for 10 minutes to remove the solvent. The final film thickness was about 30 μm. The lens array (30, FIG. 1a) and the test sample (20, FIG. 1a) were scanned at 125 μm / sec with a collimated beam (average power: 650 mW) and 0.1 cm²Area was exposed for 40 seconds. The exposed samples were developed with N, N-dimethylformamide, washed in isopropyl alcohol and dried in air. FIG. 7 shows a scanning micrograph of the structure obtained under the test conditions of Example 2.
[0144]
In Examples 3-5, the collimated beam was split into a plurality of focused spots using a square array of diffractive lenses. The lens pitch was 1.0 mm in both the horizontal and vertical directions, and the filling ratio was 100%. Each lens was a two-wave design, multi-level diffractive element with a designed focal length of 10.0 mm at 633 nm.
[0145]
Example 3
FIG. 8 shows the apparatus used in the third embodiment. As shown in this figure, the exposure system 610 included an array of diffractive lenses 620 held by shims 612 and 614 on a substrate 630. The array 620 includes a diffractive lens 622 and focused the incident light 640 at a focal point 614 (ie, 614a-614c). Substrate 630 included a layer of protective composition 634 coated on slide 632 at interface 636 with microscope slide 632. The position of the array 630 was adjusted so that the focus 614 of the diffractive lens 622 substantially coincided with the substrate / polymer interface 636. The laser beam was magnified about 5 times using a Galileo telescope set to completely fill at least four diffractive lenses 622. The diffractive lens array 620 and test sample 630 were collimated and scanned together at 125 μm / sec using an expanded laser beam (230 mW average power). A test sample identical to that described in Example 2 was prepared, exposed, developed in N, N-dimethylformamd, washed with isopropyl, and air dried.
[0146]
9 and 10 show scanning micrographs of the structure obtained under the image forming conditions of Example 3. The pattern of the reactive polymer corresponding to the spacing and symmetry of the diffractive lens array is shown. The shape of the posts here is more irregular than in Example 2, indicating that the light collection characteristics of the array 620 are more complex.
[0147]
Example 4
In Example 4, a square array of diffractive lenses was fixed relative to the laser beam and the substrate was scanned from below. With this optical configuration, an arbitrary pattern could be created with a plurality of image forming spots. The size of the laser beam was magnified about 5 times using a Galileo telescope set to completely fill at least four diffractive lenses, and the position of the zone plate was such that the focal point was approximately the substrate / polymer interface. Adjusted to match (see FIG. 8). Any arbitrary test pattern could be written using such an optical configuration. In this example, the stage was programmed to create two combined square test patterns. The same test sample as in Example 2 was prepared and exposed by scanning from below at 125 μm (230 mW average laser power). Samples were developed in N, N-dimethylformamd, washed with isopropyl and air dried. FIG. 11 shows an optical micrograph of the structure obtained under the image forming conditions of Example 4. The test pattern was reproduced on each of four different imaging spots. The polymer showed good adhesion to the substrate.
[0148]
Example 5
Example 5 illustrates imaging using hybrid polymer based patterned light. The hybrid polymer consisted of a thermoplastic substrate with reactive monomers. The refractive index and density of the photoreactive composition were increased in the illuminated area as a result of polymerization and subsequent monomer diffusion into the illuminated area. After the desired structure is obtained, the entire film can be blanket exposed using a one-photon light source to permanently fix the image.
[0149]
The photoreactive compositions shown in Table 2 were prepared as about 40% solutions in 1,2-dichloroethane and spin-coated on microscope slides. The coated slide was then heated in an 80 ° C. oven for 10 minutes to remove solvent (final film thickness was about 30 μm). The same optical configuration and pattern as in Example 4 were used. The substrate was scanned at 125 μm (average output: 230 mW). Following imaging, the test samples were exposed using three Philips @ TLD @ 3W light for 45 minutes to fix the image.
[0150]
FIG. 12 shows an optical microscope photograph of a refractive index object image. The test pattern was reproduced at each of the different imaging spots.
[0151]
[Table 2]

[0152]
Example 6
FIG. 13 shows an exposure system 710 used in the sixth embodiment. Cornng @ SMF-28 single mode optical fiber was used as a linear array of cylindrical lenses 720 for imaging. The same test board 730 as in the case of Example 2 was produced. The sheath of the optical fiber was removed using a fiber stripper and then lightly pressed against the surface of the unreacted test sample 730 shown in FIG. Then, the substrate 730 was raster-scanned at 250 μm using a collimated laser beam 740 (average output: 640 mW). The Y stage moved about half the beam diameter for each scan. Following imaging, test samples were developed in N, N-dimethylformamide, washed with isopropyl alcohol, and air dried. FIGS. 14 and 15 show the scan results of the high aspect ratio polymer lines created.
[0153]
Example 7
As shown in FIG. 16, a chirped grating 812 having an interference pattern 820 (eg, a grating in which the spacing between lines decreases for each continuous fringe) is formed by an interference fringe created by a combination of a plane wave 860 and a cylindrical wave 850. -Formed in the photoreactive composition 834 using a pattern. A linear interference fringe was formed using a combination of two plane waves (having a propagation direction that is neither parallel nor anti-parallel and incident on the image plane). Placing a cylindrical lens 840 (the uniform axis of the lens 840 is parallel to the interference fringe 826 from the original configuration) in one beam path created a parallel interference fringe 826 with a chirp period. This approach is well known in the art related to optical Bragg grating fabrication (see, for example, R. Kashapap, Fiber Bragg Gratings, Academic Press, 1999). As shown in FIG. 16, the fringe period at the left end 822 of the grating 820 is smaller (as a result of the increased angle of incidence) compared to the case without the cylindrical lens. The period at the right end 824 of the grid was not affected. The chirp rate of the interference pattern 820 changes the focal length of the cylindrical lens 840 and / or changes the distance between the lens 840 and the interference surface, or within the second beam 860 (with the same orientation). ) It can be controlled by arranging a cylindrical lens.
[0154]
The short pulses used in the multigrating absorption exposure system caused a small portion of the interference pattern to react during each laser pulse. Thus, by precisely matching the wavelengths of both beams 850 and 860, the pulses could be superimposed to form selected areas of the three-dimensional interference pattern 820. This wavelength matching operation was performed by passing the beams 850 and 860 through individual optical delay lines (see Kirkparrick, et. Al., APPli. His. A, 69, 461). By carefully adjusting the beam wavelengths relative to each other, successive laser pulses can be used to react portions of the chirped interference pattern 820.
[0155]
Example 8
This example discusses the use of three-beam interference to form multiple photovalency regions using a multiphoton absorption process. It is well known that the interference between two coherent beams in spacetime creates a pattern with high and low intensity fringes, the periodicity of which depends on the angle between the input beams. In this example, three coherent pulsed laser beams are used to form a two-dimensional array of light and dark regions, which are used to form a corresponding two-dimensional array of photopolymerized regions on a single imaging surface. Formed.
[0156]
The writing laser was an enhanced Ti: Sapphire laser producing 800 mW at 1800 nm, 1 kHz and a pulse width of 120 fs. TEM from laser₀₀The output was passed through two beam splitters to generate three independent beams of approximately equal intensity. The two optical arrays of these beams included independent optical delay lines and glass wedges. By rotating the mount, the optical path length can be finely adjusted. These beams were recombined with the sample as shown in FIG. 5 so that the angle between each beam was approximately 120 degrees. For the alignment of the light n, only the first two beams (one with a delay line and the other without it) were allowed to interfere. The length of the optical delay line was adjusted until the pulses from these first two laser beams were confirmed by observation of a two-photon fluorescence and a sharp increase in the intensity of the fringe interference pattern. A third beam was then introduced and the length of the optical delay was again adjusted until a sharp increase in the intensity of the two-photon fluorescence and interference pattern was observed.
[0157]
Solution containing 40% by weight cellulose acetate butyrate (40% solids in 1,2-dichloroethane) (n is about 1.46, Eastman Chemicals, Kingport, TN), 23% by weight phenoxy methacrylate (Sartmer Company, West Chester) , PA), 34% by weight bisphenol A glycerolate diacrylate (Ebecryl 3700, UCS Chemicals, Symra, GA), 2% by weight diaryliodonium salt (Sartmer Company, West Chester, PA), and 1% by weight bis- [ 4- (Diphenylamino) styryl] -1,4- (dimethoxy) benzene was prepared. This solution was coated on an approximately 100 micron thick silicon wafer and dried in an oven at 80 ° C. The test sample was positioned such that the three beams were interference exposed in the coating to provide a two-dimensional hexagonal honeycomb pattern on a single image plane. The refractive index modulation of the reacted area was at least 0.005 relative to the subsequently reacted substrate. The coating was blanket exposed in a non-image-wide manner using three Philips TLD 3W-05 bulbs, setting the main power to 450 nm for 30 minutes. This film maintained a refractive index modulation of at least 0.005 for the patterned areas.
[0158]
The entire disclosures of the patents, patent documents, and publications cited herein are hereby incorporated by reference in their entirety, as well as each individually. Various modifications and alterations will readily occur to those skilled in the art without departing from the scope and spirit of this specification. The present invention is not limited by the embodiments and examples shown here, and the examples and embodiments are only shown as examples, and the scope of the present invention is limited only by the following claims. Is what is done.
[Brief description of the drawings]
FIG. 1a shows a microscopic optical element exposure system according to the invention.
FIG. 1b illustrates another embodiment of a microscopic optical element exposure system having microlenses having various focal lengths according to the present invention.
FIG. 1c illustrates another embodiment that includes an array of aspherical off-axis microlenses.
FIG. 2 illustrates a diffractive optical element exposure system of the present invention in which a beam splitting diffractive optical element (DOE) is used.
FIG. 3 is a diagram showing a diffractive optical element exposure system in which a wavefront transformation DOE is used.
FIG. 4 illustrates an exposure system that creates an interference pattern in a photoreactive composition by combining parallel plane waves and divergent spherical waves.
FIG. 5 illustrates one implementation of an exposure system that includes a combination of three or more beams having the same or substantially different wavefronts to induce multiphoton absorption at selected regions within a photoreactive composition. FIG.
FIG. 6 illustrates a system including a series of adjustable plane mirrors used to steer a beam from an array of microlenses to a photoreactive composition.
FIG. 7 shows a scanning electron micrograph of a structure obtained under test conditions of Example 2.
FIG. 8 is a diagram illustrating an exposure system used in a third embodiment including an array of diffractive lenses.
FIG. 9 is a scanning electron micrograph of the structure obtained under the image forming conditions of Example 3.
FIG. 10 is a scanning electron micrograph of a structure obtained under image forming conditions of Example 3.
FIG. 11 is an optical micrograph of the structure obtained under the image forming conditions of Example 4.
FIG. 12 is an optical micrograph of a refractive index control image.

Claims (35)

In a method of creating a region of at least partially reacted material in a photoreactive composition,
Providing a photoreactive composition;
Providing a source of light sufficient for the photoreactive composition to absorb at least two photons simultaneously;
Providing an exposure system including at least one diffractive optical element and capable of inducing image-like multiphoton absorption;
Generating a non-random three-dimensional light pattern by the exposure system;
Exposing the photoreactive composition to the three-dimensional light pattern generated by the exposure system to at least partially react a portion of the material with the non-random three-dimensional light pattern incident thereon; And a method comprising: The method of claim 1 wherein the exposing comprises a pulsed irradiation step. 3. The method of claim 2, wherein said step of pulsing is performed using a near infrared pulsed laser having a pulse length of less than about 10 nanoseconds. The method of claim 1, wherein the diffractive optical element is a diffraction mask. The photoreactive composition comprises from about 5 to about 99.79% by weight, based on the total weight of the solid, of at least one reactive species and from about 0.01 to about 10% by weight of at least one multiphoton photomultiplier. The method of claim 1, comprising a sensitizer, up to about 10% by weight of at least one electron donor compound, and about 0.1% to about 10% by weight of at least one photoinitiator. The method of claim 1, wherein the diffractive element is capable of performing beam splitting, wavefront transformation, or both. In a method of creating a region of at least partially reacted material in a photoreactive composition,
Providing a photoreactive composition;
Providing a source of light sufficient for the photoreactive composition to absorb at least two photons simultaneously;
Providing an exposure system comprising at least one array of diffractive micro-optical elements and capable of inducing image-like multiphoton absorption;
Generating a non-random three-dimensional light pattern by the exposure system;
Exposing the photoreactive composition to the three-dimensional light pattern generated by the exposure system to at least partially react a portion of the material with the non-random three-dimensional light pattern incident thereon; And a step. The method of claim 7, wherein the exposing comprises a pulsed irradiation step. 9. The method of claim 8, wherein the step of pulsing is performed using a near infrared pulsed laser having a pulse length of less than about 10 nanoseconds. The method of claim 7, wherein the refractive micro-optical element comprises an array of optical fibers. The photoreactive composition comprises about 5 to about 99.79% of at least one reactive species and about 0.01 to about 10% by weight of at least one multiphoton photomultiplier, based on the total weight of the solid. 19. The method of claim 18, comprising a sensitizer, up to about 10% by weight of at least one electron donor compound, and about 0.1 to about 10% by weight of at least one photoinitiator. Providing a photoreactive composition;
Providing a source of light sufficient for the photoreactive composition to absorb at least two photons simultaneously;
An exposure system capable of inducing image-like multiphoton absorption, comprising: a first beam having a first wavefront shape; and a second wavefront shape substantially different from said second wavefront shape. Providing an exposure system comprising:
Generating a non-random three-dimensional light pattern by said exposure system using optical interference between a first light beam and a second light beam;
Exposing the photoreactive composition to the three-dimensional light pattern generated by the exposure system, and at least partially reacting a portion of the material in response to the non-random three-dimensional light pattern incident thereon; Creating a region of the at least partially reacted material in the photoreactive composition. 13. The method of claim 12, wherein the exposing comprises a pulsed irradiation step. 14. The method of claim 13, wherein the step of pulsing is performed using a near infrared pulsed laser having a pulse length of less than about 10 nanoseconds. 13. The method of claim 12, wherein said light source comprises a pulsed laser. The photoreactive composition comprises about 5 to 99.79% by weight of the at least one reactive species and about 0.01 to about 10% by weight of the at least one multiphoton, based on the total weight of the solid. 13. The method of claim 12, comprising a photosensitizer, up to about 10% by weight of said at least one electron donor compound, and about 0.1 to about 10% by weight of said at least one photoinitiator. Providing a photoreactive composition;
Providing a source of light sufficient for the photoreactive composition to absorb at least two photons simultaneously;
An exposure system capable of inducing image-like multiphoton absorption, comprising: three or more light beams, each of said three or more light beams having a wavefront having one shape. Providing an exposure system having a wavefront shape that is the same as or substantially different from the wavefront shape of the other light beam;
Generating a non-random three-dimensional light pattern by said exposure system using optical interference from three or more light beams;
Exposing the photoreactive composition to the three-dimensional light pattern generated by the exposure system, and at least partially reacting a portion of the material in response to the non-random three-dimensional light pattern incident thereon; Creating a region of the at least partially reacted material in the photoreactive composition. 18. The method of claim 17, wherein said exposing comprises performing pulsed irradiation. 19. The method of claim 18, wherein the step of providing pulsed irradiation is performed using a near infrared pulsed laser having a pulse length of less than about 10 nanoseconds. The method according to claim 17, wherein the light source comprises a pulsed laser. The photoreactive composition comprises about 5 to 99.79% by weight of the at least one reactive species and about 0.01 to about 10% by weight of the at least one multiphoton, based on the total weight of the solid. 13. The method of claim 12, comprising a photosensitizer, up to about 10% by weight of said at least one electron donor compound, and about 0.1 to about 10% by weight of said at least one photoinitiator. A photoreactive composition;
A source of light sufficient for the photoreactive composition to absorb at least two photons simultaneously;
An exposure system that includes at least one diffractive optical element;
The exposure system can induce image-like multiphoton absorption, the exposure system can generate a non-random three-dimensional light pattern, and the exposure system can correspond to the non-random three-dimensional light pattern. A device for reacting a photoreactive composition, wherein at least a portion of the substance is allowed to react. 23. The device of claim 22, wherein said light source comprises a pulsed laser. The photoreactive composition comprises about 5 to 99.79% by weight of the at least one reactive species and about 0.01 to about 10% by weight of the at least one multiphoton, based on the total weight of the solid. 23. The method of claim 22, comprising a photosensitizer, up to about 10% by weight of said at least one electron donor compound, and about 0.1 to about 10% by weight of said at least one photoinitiator. 23. The apparatus of claim 22, wherein the diffractive optical element is capable of performing beam splitting, wavefront transformation, or both. 23. The apparatus of claim 22, wherein said diffractive optical element is a diffraction mask. A photoreactive composition;
A source of light sufficient for the photoreactive composition to absorb at least two photons simultaneously;
An exposure system including at least one array of refractive micro-optics;
The exposure system can induce image-like multiphoton absorption, the exposure system can generate a non-random three-dimensional light pattern, and the exposure system can correspond to the non-random three-dimensional light pattern. A device for reacting a photoreactive composition, wherein at least a portion of the substance is allowed to react. 28. The device of claim 27, wherein said light source comprises a pulsed laser. The photoreactive composition comprises about 5 to 99.79% by weight of the at least one reactive species and about 0.01 to about 10% by weight of the at least one multiphoton, based on the total weight of the solid. 28. The method of claim 27, comprising a photosensitizer, up to about 10% by weight of said at least one electron donor compound, and about 0.1 to about 10% by weight of said at least one photoinitiator. 28. The apparatus of claim 27, wherein said array of refractive micro-optics comprises one array of optical fibers. A photoreactive composition;
A source of light sufficient for the photoreactive composition to absorb at least two photons simultaneously;
An exposure system comprising a first light beam having a first wavefront shape and a second light beam having a second wavefront shape substantially different from said second wavefront shape;
The exposure system can induce image-like multiphoton absorption, the exposure system can generate a non-random three-dimensional light pattern, and the exposure system can correspond to the non-random three-dimensional light pattern. An apparatus for reacting a photoreactive composition, wherein at least a portion of the substance can be at least partially reacted. 32. The device of claim 31, wherein said light source comprises a pulsed laser. The photoreactive composition comprises about 5 to 99.79% by weight of the at least one reactive species and about 0.01 to about 10% by weight of the at least one multiphoton, based on the total weight of the solid. 32. The apparatus of claim 31, comprising a photosensitizer, up to about 10% by weight of said at least one electron donor compound, and about 0.1 to about 10% by weight of said at least one photoinitiator. A photoreactive composition;
A source of light sufficient for the photoreactive composition to absorb at least two photons simultaneously;
An exposure system that includes three or more light beams;
Each of the three or more light beams has a wavefront having one shape, and each of the three or more light beams has a wavefront shape that is the same as or substantially different from the wavefront shape of the other light beams. Wherein said exposure system is capable of inducing image-like multiphoton absorption, said exposure system is capable of generating a non-random three-dimensional light pattern, and wherein said exposure system is capable of generating said non-random three-dimensional light pattern. An apparatus for reacting a photoreactive composition, the apparatus being capable of at least partially reacting a portion of the substance in response to the above. The photoreactive composition comprises about 5 to 99.79% by weight of the at least one reactive species and about 0.01 to about 10% by weight of the at least one multiphoton, based on the total weight of the solid. 35. The apparatus of claim 34, comprising a photosensitizer, up to about 10% by weight of said at least one electron donor compound, and about 0.1 to about 10% by weight of said at least one photoinitiator.