JP3870680B2 - Fluorescent printing inks containing organic lanthanoid complexes - Google Patents

Description

【００２６】
【化２】

【００２７】
かかるデンドロンの世代数に特に制限はないが、通常１〜６世代、合成の容易性から好ましくは１〜４世代（発光効果の点で好ましくは２〜４世代）、合成容易性と発光効果のバランスから最も好ましくは１〜３世代とする。
本発明に好適なカルボキシレート錯体の具体的な構造例としては、下記一般式（３）〜（８）において置換基Ｒが全て水素原子である構造式により表されるポリベンジルエーテルデンドロンを配位子とするランタノイド錯体が挙げられる。
【００２８】
【化３】

【００２９】
【化４】

【００３０】
【化５】

【００３１】
【化６】

【００３２】
【化７】

【００３３】
【化８】

【００３４】
但し、前記一般式（３）〜（５）中のＬｎ³⁺はＴｂ³⁺またはＥｕ³⁺を表し、前記一般式（３）〜（８）中のＲは水素原子又はビニル基を表す。
前記一般式（３）〜（８）において置換基Ｒが全て水素原子である例示のうち、一般式（４）または（７）で表される第２世代ポリベンジルエーテルデンドロンカルボキシレートを配位子とする錯体は、合成容易性と輝度のバランス点で非常に好ましく、一般式（３）または（６）で表される第１世代ポリベンジルエーテルデンドロンカルボキシレートを配位子とする錯体は、錯体の単位重量当たりの輝度の点で実用的に非常に有用である。
【００３５】
＜好適なβ−ジケトネート型Ｅｕ³⁺錯体＞
本発明の印刷用インクに好適なＥｕ³⁺とβ−ジケトネート基を有する配位子により構成される蛍光性の有機ランタノイド錯体は、下記一般式（９）で表されるものである。
【００３６】
【化９】

【００３７】
但し、一般式（９）において、Ｒは炭素数６以下のアルキル基または炭素数６以下のフッ化アルキル基を、Ｒ’は芳香族基をそれぞれ表す。好適なＲとしては、例えばメチル基、エチル基、ｎ−ブチル基、ｎ−ヘキシル基等の直鎖アルキル基、イソプロピル基、イソブチル基等の分岐を有するアルキル基、トリフルオロメチル基、ペンタフルオロエチル基、ヘプタフルオロプロピル基、ノナフルオロブチル基等の直鎖状パーフルオロアルキル基、ヘプタフルオロイソプロピル基、ノナフルオロイソブチル基等の分岐を有するパーフルオロアルキル基等が挙げられ、より好適なのはトリフルオロメチル基、ペンタフルオロエチル基、ヘプタフルオロプロピル基、ノナフルオロブチル基等の直鎖状パーフルオロアルキル基、およびヘプタフルオロイソプロピル基等の炭素数４以下のパーフルオロアルキル基、更に好適なのはトリフルオロメチル基、ペンタフルオロエチル基、ヘプタフルオロプロピル基等の炭素数３以下のパーフルオロアルキル基、最も好適なのはトリフルオロメチル基である。一方、好適なＲ’としては、フェニル基、ナフチル基、アントラセニル基、ピレニル基等の芳香族炭化水素基、チエニル基（又はテノイル基）やフラニル基（又はフロイル基）等の硫黄原子や酸素原子等のヘテロ原子を含有する芳香族基等が挙げられ、中でもフェニル基またはナフチル基がより好適で、ナフチル基が最も好適である。従って、本発明に好適な具体的な構造例としては、下記式（１０）で表されるナフチル基を有する構造、あるいは式（１０）のナフチル基がフェニル基で置換された構造等が挙げられ、中でも式（１０）の化合物（以下、Ｅｕ（ＮＴＡ）₃と略記）が最適である。なお、Ｅｕ（ＮＴＡ）₃は蛍光免疫分析用蛍光体として使用されており、例えば前記のＪ．Ｙｕａｎら著の文献、あるいはＥ．Ｐ．Ｄｉａｍａｎｄｉｓ；Ｃｌｉｎ．Ｂｉｏｃｈｅｍ．，２１巻，１３９頁（１９８８）等に解説されている。
【００３８】
【化１０】

【００３９】
ここで例示したＥｕ³⁺とβ−ジケトネート基を有する配位子により構成される蛍光性の有機ランタノイド錯体は、後述する懸濁液インクの材料として特に好適である。
＜重合性を有する有機ランタノイド錯体＞
後述する本発明の重合性インクの材料として、重合性を有する有機ランタノイド錯体は好適である。ここで言う重合性とは、任意の重合形式における重合性を意味し、重合形式としては、ラジカル重合、アニオン重合、カチオン重合、配位重合、開環重合、縮重合等が例示されるが、特にラジカル重合が好ましい。かかる重合性は、通常、有機配位子に重合性を有する官能基（以下、重合性基と呼ぶ）を導入して付与される。かかる目的に好適なのは、ラジカル重合性基等の重合性基を結合したデンドロンを配位子として含有する有機ランタノイド錯体である。
【００４０】
前記のラジカル重合性基としては、芳香環と共役した炭素−炭素多重結合（例えば４−ビニルフェニル基や３−ビニルフェニル基等のスチレン残基、４−プロパルギルフェニル基、あるいはビニルナフタレン残基等の共役炭化水素構造、４−ビニルピリジル基や２−ビニルピリジル基等のビニルピリジン残基等の含窒素芳香環と共役した構造等）、アクリロイル基、メタクリロイル基、あるいはクロトノイル基等のアクリル酸、メタクリル酸、あるいはクロトン酸等の不飽和共役カルボン酸から誘導される共役炭化水素残基、マレイノイル基やフマロイル基等のマレイン酸やフマル酸等の不飽和共役ジカルボン酸から誘導される共役炭化水素残基、アリル基を有する構造（例えば４−アリルフェニル基、４−アリルオキシフェニル基、４−アリルオキシカルボニルフェニル基等）、ビニルエーテル構造やビニルエステル構造を有する構造（例えば４−ビニルオキシフェニル基、４−ビニルオキシカルボニルフェニル基等）が挙げられる。
【００４１】
後述する重合性インクにおける重合反応性の点で、前記の重合性基はデンドロンの非フォーカルポイント末端に結合されていることが望ましい。また、１つのデンドロン中でのかかる重合性基の数に制限はないが、重合反応中における過度のゲル化を防ぐために、該重合性基の数は通常１〜８、好ましくは１〜６、更に好ましくは１〜４、最も好ましくは１〜３の自然数とする。
【００４２】
本発明に好適に使用されるラジカル重合性デンドロンを配位子とする有機ランタノイド錯体の具体的な構造例としては、前記一般式（３）〜（８）において置換基Ｒが全てビニル基である、４−ビニルフェニル基末端を有するポリベンジルエーテルデンドロンを配位子とするランタノイド錯体が挙げられ、これらの中でも前記一般式（４）または（７）で表される第２世代ポリベンジルエーテルデンドロンカルボキシレートを配位子とする錯体は、合成容易性と輝度のバランス点で非常に好ましく、前記一般式（３）または（６）で表される第１世代ポリベンジルエーテルデンドロンカルボキシレートを配位子とする錯体は、錯体の単位重量当たりの輝度の点で実用的に非常に有用である。なお前記一般式（３）〜（８）に例示の構造において、含有される４−ビニルフェニル基末端が、デンドロン構造中の任意の非フォーカルポイント末端に置き換わった異性体が同様のラジカル重合性を有することは言うまでもなく、また１つのデンドロン構造中に前記のように最大３つ程度の４−ビニルフェニル基末端が含有されていても好ましい重合性を発揮する。
【００４３】
＜溶液型インク＞
前記の有機ランタノイド錯体を任意の溶剤に溶解した溶液は、本発明の印刷用インクとして使用可能である。かかる溶液から製造される印刷用インクをここでは「溶液型インク」と呼ぶ。
かかる溶液型インクにおける前記の有機ランタノイド錯体の濃度は、通常０．０１〜９０重量％、蛍光能、溶解性、及び溶液粘度等の印刷性の点で好ましくは０．１〜７５重量％、更に好ましくは１〜６０重量％、最も好ましくは５〜４０重量％程度とし、かかる濃度で溶解させる限りにおいて該溶液型インクの製造方法に制限はない。
【００４４】
かかる溶液型インクに使用される溶剤としては、トルエン、キシレン、スチレン、α−メチルスチレン、クロロベンゼン等の芳香族炭化水素類、テトラヒドロフラン（通称ＴＨＦ）、メチルセロソルブ、エチルセロソルブ、ジエチルエーテル、ベンジルメチルエーテル等のエーテル類、酢酸メチル、酢酸エチル、酢酸ブチル、酢酸ベンジル、プロピオン酸エチル、アクリル酸エチル、メタクリル酸メチル、メタクリル酸ｎ−ブチル等のカルボン酸エステル類、塩化メチレン、クロロホルム、１，１，１−トリクロロエタン、ｓｙｍ−テトラクロロエチレン等のハロゲン化アルキル類、アセトンやメチルエチルケトン等のケトン類、Ｎ，Ｎ−ジメチルアセトアミド、Ｎ，Ｎ−ジメチルホルムアミド（通称ＤＭＦ）、Ｎ−ビニルホルムアミド、Ｎ−メチルピロリドン（通称ＮＭＰ）、Ｎ−ビニルピロリドン等の非プロトン性アミド系溶媒、ジメチルスルホキシド（通称ＤＭＳＯ）やジブチルスルホキシド等のスルホキシド類、メタノール、エタノール、ｎ−プロパノール、イソプロピルアルコール、ｎ−ブタノール、イソブチルアルコール、ｔｅｒｔ−ブチルアルコール等の低級アルコール類、エチレングリコール、プロピレングリコール、ブチレングリコール等の低級グリコール類、グリセリン、エリスリトール、ペンタエリスリトール、２−エチル−２−ヒドロキシメチル−１，３−プロパンジオール等の多価アルコール類、あるいは水等が挙げられる。これらの溶剤は、必要に応じて複数種を組み合わせて用いても構わない。
【００４５】
なお、ここで例示した溶剤のうち、スチレン、α−メチルスチレン、アクリル酸エチル、メタクリル酸メチル、メタクリル酸ｎ−ブチル、Ｎ−ビニルホルムアミド、あるいはＮ−ビニルピロリドン等のラジカル重合性の炭素−炭素多重結合を有する溶剤は、後述する重合性インク用の溶剤として特に有効である場合がある。
【００４６】
これらのうち、前記の芳香族デンドロン配位子を含有する有機ランタノイド錯体を原料とする場合に好適な溶剤は、トルエン、キシレン、スチレン、クロロベンゼン等の芳香族炭化水素類、ＴＨＦやベンジルメチルエーテル等のエーテル類、酢酸エチル、酢酸ブチル、酢酸ベンジル、メタクリル酸メチル、メタクリル酸ｎ−ブチル等のカルボン酸エステル類、塩化メチレン等のハロゲン化アルキル類、アセトンやメチルエチルケトン等のケトン類、Ｎ，Ｎ−ジメチルアセトアミド、ＤＭＦ、ＮＭＰ等の非プロトン性アミド系溶媒、ＤＭＳＯ等のスルホキシド類等であり、中でもトルエンやクロロベンゼン等の芳香族炭化水素類、ＴＨＦ等のエーテル類、酢酸エチル等のカルボン酸エステル類、塩化メチレン等のハロゲン化アルキル類、アセトン等のケトン類、ＤＭＦやＮＭＰ等の非プロトン性アミド系溶媒等が溶解度の点で特に好適である。
【００４７】
＜重合性インク＞
本発明の印刷用インクが重合性成分を含有する場合をここでは「重合性インク」と呼ぶ。該重合性成分としては、前記のような重合性を有する有機ランタノイド錯体、あるいは前記のラジカル重合性の炭素−炭素多重結合を有する溶剤等が具体的に挙げられる。かかる重合性インクは、有機ランタノイド錯体が溶解している前記の溶液型インクとして、あるいは後述する有機ランタノイド錯体の微粒子が溶媒中に懸濁安定化された懸濁液型インクのいずれの形式としても可能である。なお、後者の懸濁液型インクの場合に重合性を有する有機ランタノイド錯体の微粒子を用いると、該微粒子表面に該重合性基が存在する場合があり、かかる微粒子は重合性成分の１種と考えられる。
【００４８】
本発明における重合性インクは、前記の任意の重合形式（特に好適なのはラジカル重合）により印刷後のインク中で重合反応を進行させることにより、高分子の生成、より好ましくは架橋高分子の生成を意図するものである。かかる高分子の生成により、印刷されたインク成分の溶剤溶解性を大きく減少させたり、摩擦、加熱、酸化、光劣化等の印刷を劣化させる外部要因に対する耐久性を著しく向上させる好ましい効果が見られる場合がある。特に好ましいのは前記の重合性を有する有機ランタノイド錯体の使用である。これは、本発明の印刷用インクの蛍光能の源泉である蛍光物質自体を高分子に共重合させ固定する効果による。
【００４９】
かかる重合性インク中の重合性成分の割合は、全インク重量に対して通常１〜１００重量％、前記の高分子の生成による効果の点で好ましくは１０〜１００重量％、更に好ましくは２０〜１００重量％、最も好ましくは３０〜１００重量％とする。
架橋高分子を重合反応により生成させる目的で、適当な架橋剤を添加することがしばしば好ましい結果を与える。かかる架橋剤をラジカル重合の場合を例に挙げると、１分子中に複数のラジカル重合性基を含有する化合物、即ち、ジビニルベンゼン等の多官能ベンゼン、Ｎ，Ｎ’−メチレンビス（メタ）アクリルアミド、Ｎ，Ｎ’−エチレンビス（メタ）アクリルアミド、Ｎ，Ｎ’−ブチレンビス（メタ）アクリルアミド、エチレングリコールジ（メタ）アクリレート、ブチレングリコールジ（メタ）アクリレート、ペンタエリスリトールトリアクリレート、ペンタエリスリトールテトラアクリレート等の２つ以上の（メタ）アクリロイル基を有する化合物、アジピン酸ジビニル、（メタ）アクリル酸ビニル、クロトン酸ビニル等の２官能ビニルエステル類等が例示される。これらのうち一般的に用いられる重要なものはジビニルベンゼン、Ｎ，Ｎ’−メチレンビスアクリルアミド、エチレングリコールジアクリレート、アジピン酸ジビニル、アクリル酸ビニル等である。かかる架橋剤の使用量は、全重合性分子中のモル分率として、通常０．００１〜５％、好ましくは０．０１〜４％、更に好ましくは０．０５〜３．５％、最も好ましくは０．１〜３％程度とする。
【００５０】
重合性インクに添加する重合性成分として、前記のラジカル重合性の炭素−炭素多重結合を有する溶剤以外に、公知の任意のラジカル反応性モノマーの使用が可能である。具体的には、４−アセトキシスチレン、４−クロロメチルスチレン等のスチレン類、Ｎ，Ｎ−ジメチルアミノエチル（メタ）アクリレート等の（メタ）アクリル酸エステル類、メチルクロトネート、ｎ−ブチルクロトネート、ベンジルクロトネート、Ｎ，Ｎ−ジメチルアミノプロピルクロトネート等のクロトン酸エステル類、（メタ）アクリル酸やクロトン酸等の不飽和共役カルボン酸、（メタ）アクリルアミド、Ｎ−メチル（メタ）アクリルアミド、Ｎ，Ｎ−ジメチル（メタ）アクリルアミド、Ｎ，Ｎ−ジエチル（メタ）アクリルアミド、Ｎ，Ｎ−ジメチルアミノプロピル（メタ）アクリルアミド、Ｎ−（メタ）アクリロイルモルホリン、Ｎ−イソプロピル（メタ）アクリルアミド等の（メタ）アクリルアミド類、クロトニルアミド、Ｎ−メチルクロトニルアミド、Ｎ，Ｎ−ジメチルクロトニルアミド、Ｎ−クロトニルモルホリン、Ｎ−イソプロピルクロトニルアミド等のクロトニルアミド類、酢酸ビニル、モノクロロ酢酸ビニル、ピバル酸ビニル、酪酸ビニル、２−エチルヘキサン酸ビニル等のカルボン酸のビニルエステル類、（メタ）アクリロニトリル等のニトリル類、無水マレイン酸、マレイン酸、フマル酸、マレイン酸ジエチル、フマル酸ジメチル、マレイン酸のモノエチルエステル、マレイミド、Ｎ−メチルマレイミド、Ｎ−フェニルマレイミド等の共役不飽和ジカルボン酸誘導体等、Ｎ−ビニルオキサゾリン等が例示される。
【００５１】
重合性インクにおける重合反応を進行させる条件に制限はないが、ラジカル重合の場合は、通常熱あるいは光の印加によるラジカル発生より重合を開始する。かかるラジカル発生剤の使用量は、該重合性インク中の全ラジカル重合性成分の重量に対して通常０．００１〜１０重量％、好ましくは０．０１〜５重量％、更に好ましくは０．０５〜３重量％、最も好ましくは０．１〜２重量％程度とする。ラジカル重合を意図する重合性インクに使用される熱ラジカルの発生剤として一般的なものとしては、Ｎ，Ｎ’−アゾビスイソブチロニトリル（通称ＡＩＢＮ）等のアゾ化合物、過酸化ベンゾイル等の過酸化物等が最も一般的に用いられるが、水溶性のラジカル発生剤、例えば過硫酸カリウムや過硫酸アンモニウム等の過硫酸塩、あるいは水溶性のアゾ化合物（例えば和光純薬（株）から市販されているもの）等を使用しても構わない。また光ラジカルの発生剤として一般的なものとしては、α−アミノアセトフェノンや２−ベンジル−２−ジメチルアミノ−１−（４−モルホリノフェニル）−ブタン−１等のアミノアセトフェノン類、の他、ベンジルジメチルケタール類、グリオキシエステル類、アシルホスフィンオキシ類等が例示される。
【００５２】
前記したラジカル重合性を有するモノマー類、架橋剤、及びラジカル発生剤はいずれも、必要に応じて、それぞれ複数種を混合して用いても構わない。
＜懸濁液型インク＞
前記の有機ランタノイド錯体の微粒子を任意の溶剤に懸濁安定化した懸濁液は、本発明の印刷用インクとして使用可能である。かかる懸濁液から製造される印刷用インクをここでは「懸濁液型インク」と呼ぶ。
【００５３】
かかる懸濁液型インクに使用する溶剤に制限はなく、その具体例は前記の溶液型インクにおける例示と同一である。但し、対環境安全性や作業者の安全性の観点で、水、アルコール類等の水性溶媒の使用が特に好適である。ここで言う水性溶媒とは、水、あるいは水を含んだ均一混合溶媒を意味するが、水が最も好ましい。
【００５４】
水と混合して水性溶媒を与える物質には、水への溶解性を有し有機ランタノイド錯体への好ましくない化学反応を起こさない不活性なものである限りにおいて制限はないが、例えば、メタノール、エタノール、ｎ−プロパノール、イソプロピルアルコール、ｎ−ブタノール、イソブチルアルコール、ｔｅｒｔ−ブチルアルコール等の低級アルコール類、エチレングリコール、プロピレングリコール、ブチレングリコール等の低級グリコール類、グリセリン、エリスリトール、ペンタエリスリトール、２−エチル−２−ヒドロキシメチル−１，３−プロパンジオール等の多価アルコール類、アセトンやメチルエチルケトン等の低級ケトン類、ジエチルエーテル、テトラヒドロフラン（通称ＴＨＦ）、メチルセロソルブ、エチルセロソルブ等の脂肪族エーテル類、酢酸メチルや酢酸エチル等の低級脂肪酸のエステル類、Ｎ，Ｎ−ジメチルアセトアミド、Ｎ，Ｎ−ジメチルホルムアミド（通称ＤＭＦ）、Ｎ−メチルピロリドン（通称ＮＭＰ）等の非プロトン性アミド系溶媒、ジメチルスルホキシド（通称ＤＭＳＯ）やジブチルスルホキシド等のスルホキシド類等が挙げられる。これらの有機物質は複数を混合して用いても構わず、また水との混合比に制限はないが、水性溶媒中の水の含有量を通常５〜１００重量％、好ましくは１０〜１００重量％、更に好ましくは２０〜１００重量％、最も好ましくは３０〜１００重量％とする。
【００５５】
かかる懸濁液型インクにおいて、前記の有機ランタノイド錯体は微粒子として懸濁安定化されるが、その数平均粒径は、通常８〜１０００ｎｍ、好ましくは１５〜７００ｎｍ、更に好ましくは３０〜４００ｎｍ、最も好ましくは５０〜２００ｎｍとする。かかる粒径は、例えばコールターカウンター等の汎用の微粒子粒径測定装置、光散乱法、顕微鏡（光学顕微鏡や電子顕微鏡）等により測定される。
【００５６】
前記の懸濁液型インクにおける前記の有機ランタノイド錯体の含有量は、該錯体の分子量にも大きく依存するが、ランタノイド元素の濃度としては通常０．００１〜１００ミリモル／Ｌ、懸濁液の発光能と懸濁安定性とのバランスから好ましくは０．００５〜５０ミリモル／Ｌ、更に好ましくは０．０１〜２０ミリモル／Ｌ、最も好ましくは好ましくは０．０５〜５ミリモル／Ｌ程度とする。また、有機ランタノイド錯体の重量割合としては、通常０．００１〜５０重量％、懸濁液型インクの発光能と懸濁安定性とのバランスから好ましくは０．０１〜３０重量％、更に好ましくは０．１〜２０重量％、最も好ましくは１〜１０重量％とする。かかる有機ランタノイド錯体の含有量は、該懸濁液型インクからの溶媒の蒸留残渣の重量分析、該残渣の元素分析、該懸濁液型インクを加熱燃焼した場合の灰分分析、該懸濁液型インクのＮＭＲスペクトルや赤外吸収スペクトル等の各種定性・定量分析又はそれらの組み合わせにより測定可能である。
【００５７】
＜水性懸濁液型インクの製造方法＞
特に好ましい水性溶媒を使用した懸濁液型インクの製造方法として、界面活性剤の存在下、水性溶媒中に分散した有機ランタノイド錯体を力学的破砕により懸濁安定化せしめる方法（以下、破砕法と呼ぶ）が例示できる。かかる方法について以下に説明する。
【００５８】
前記の破砕法において、まず有機ランタノイド錯体を機械的にできるだけ細かく粉体としておく操作（以下、前粉砕と呼ぶ）を行うのが好ましい。これにより、後述する「力学的破砕」による微粒子化が容易となる。かかる前粉砕は、既存の任意の粉砕装置（例えば、「乳鉢とすりこぎ」の原理によるすりつぶし装置、回転釜やベルト等の運動体と該運動体とのあいだに間隙を形成する圧縮体とを有しかかる間隙でのせん断力を利用する装置、ボールミル等の移動物体の運動エネルギーにより粉砕する装置、壁面への衝突の運動エネルギーにより粉砕する装置、等）で行って構わず、かかる前粉砕で得られる粉体の数平均粒径は、通常０．８〜１０００μｍ、好ましくは０．８〜５００μｍ、更に好ましくは０．８〜１００μｍ、最も好ましくは０．８〜５０μｍ程度とする。
【００５９】
かかる前粉砕により得る有機ランタノイド錯体粉体を、次いで前記の水性溶媒に分散した水性分散液（以下、分散液と呼ぶ）を得る。この時適当な界面活性剤を併用すると、後述する力学的破砕において懸濁安定化の点で好ましい結果を与える場合が多い。これは、通常親油性の有機ランタノイド錯体の粉体あるいは破砕微粒子の表面を界面活性剤の親油性基が被覆し、外側に向いた界面活性剤の親水性基が有機ランタノイド錯体の粉体あるいは破砕微粒子をミセル的に水性溶媒中で安定化する効果によるものと推定される。ここで用いられる好適な界面活性剤としては、例えば、ドデシルベンゼンスルホン酸ナトリウム、ドデシルスルホン酸ナトリウム等のスルホン酸塩、パルミチン酸ナトリウム、ステアリン酸ナトリウム等のカルボン酸塩等の陽イオン性界面活性剤、テトラエチルアンモニウム等の４級オニウム塩を結合した陰イオン性界面活性剤、ポリエチレングリコール鎖等の水溶性構造を結合した非イオン性界面活性剤、ポリエチレングリコール、ポリビニルピロリドン、ポリビニルピリジン、ポリビニルアルコール等の水溶性高分子等が挙げられ、中でもドデシルベンゼンスルホン酸ナトリウム、ドデシルスルホン酸ナトリウム等のスルホン酸塩、パルミチン酸ナトリウム、ステアリン酸ナトリウム等のカルボン酸塩等の陽イオン性界面活性剤が好適である。
【００６０】
水性溶媒を使用した本発明の懸濁液型インクを得るには、前記の分散液に対して任意の力学的破砕を行う処理を施す。本発明における「力学的破砕」とは、該分散液中に存在する有機ランタノイド錯体の粉体に対して衝突、せん断、圧縮あるいは膨張等任意の力学的衝撃力を印加してこれを破砕することを意味する。かかる力学的衝撃力は、有機ランタノイド錯体の粉体どうし、該粉体と装置内壁の構造物との間、あるいは該粉体と水性溶媒との間等、該粉体の関わる任意の力学的相互作用により生じる。かかる力学的破砕の具体的方法としては、前記の分散液を硬度と強度に優れた任意の材料（例えば金属、半導体、セラミクス、ガラス、ダイヤモンド等）を内壁材質とする細管へ高圧注入する方法、前記の分散液を同様の硬度と強度に優れた任意の材料の表面に高速衝突させる方法、高圧の前記の分散液を急激に放圧させる方法等が例示され、これらのうち生産性や力学的破砕効果の点で好ましいのは、細管へ高圧注入する方法である。かかる細管への高圧注入における注入圧は、通常１００〜５０００ｋｇ／ｃｍ²、力学的破砕の効果と装置の耐圧性の点で好ましくは３００〜４０００ｋｇ／ｃｍ²、更に好ましくは５００〜３０００ｋｇ／ｃｍ²、最も好ましくは７００〜２０００ｋｇ／ｃｍ²程度の範囲とする。また、力学的破砕が起こる際の前記の分散液の温度はその時の圧力において水性溶媒の沸騰が起きない温度に制御するのが好ましく、通常は２０〜２００℃、好ましくは２０〜１５０℃、更に好ましくは２０〜１３０℃、最も好ましくは２０〜１２０℃程度とする。かかる温度は、力学的破砕の起きる装置の箇所の分散液の実温測定、あるいは近傍の材質の温度測定により見積もられる。
【００６１】
かかる例示の方法において、力学的破砕の効果を増大させる目的で、該分散液と接触する細管の内壁や表面に必要に応じて任意の立体構造物（例えば、楔形や直方体等任意形状の突起やくぼみ等の表面形状の変化、スリットや邪魔板、攪拌翼等）を設置して構わない。
かかる力学的破砕を受けて生成する有機ランタノイド錯体の破砕微粒子は、例えば前記の界面活性剤のミセル形成と類似の効果等の任意の効果により、水性溶媒中で懸濁安定化されることが望ましい。この時、例えば前記の界面活性剤の分子のような両親媒性分子、あるいはカルボニル基、水酸基、アミノ基等の極性基を有する極性分子を安定化分子として事前に該分散液に添加しておくことがしばしば良好な結果を与える。かかる安定化分子が好ましい懸濁安定化効果を示す限りにおいてその作用機構は任意であるが、例えば前記の界面活性剤におけるミセル形成と類似の機構、あるいは力学的破砕によるメカノケミカル反応によりかかる安定化分子と有機ランタノイド錯体の破砕微粒子表面との間の化学結合が新たに生成する機構、等が推測される。
【００６２】
＜重合性インクを使用した印刷方法＞
本発明の印刷用インク中の重合性成分を重合せしめる工程を含むことを特徴とする印刷方法は、前記の重合性インクの説明のとおり、印刷品質の耐久性の点で好ましいものである。特にラジカル重合を進行させる場合、熱ラジカル重合あるいは光ラジカル重合等の任意のラジカル重合行う工程を経る印刷方法が好適である。いずれのラジカル重合の場合も、後述する加熱処理が有効である。
【００６３】
熱ラジカル重合の場合、印刷後の印刷面を前記の熱ラジカル発生剤の分解温度以上に加熱する。かかる加熱温度は、通常４０〜１８０℃、重合性及び有機ランタノイド錯体の熱劣化やラジカル重合性成分の揮発防止の点で好ましくは５０〜１６０℃、更に好ましくは５５〜１４０℃、最も好ましくは６０〜１３０℃程度とする。また、この加熱時間は、加熱温度にもよるが通常１〜３６０００秒、重合性と生産性の点で好ましくは５〜１８０００秒、更に好ましくは１０〜９０００秒、最も好ましくは１５〜３６００秒程度とする。なお、該加熱時間中の加熱温度を変化させて好ましい熱ラジカル重合を設計することも可能である。例えば、加熱初期は４０〜９０℃程度の比較的低温で加熱することにより重合性成分の揮発を防ぎながらラジカルを発生させて重合を開始し、次いで９０〜１８０℃程度の高温でラジカル重合を急速に進行させる、といった反応設計が考えられる。
【００６４】
光ラジカル重合の場合、印刷後の印刷面に、前記の光ラジカル発生剤を分解せしめる波長の光をまず照射し、通常次いで重合を促進する目的で加熱する。かかる加熱の温度範囲と時間は、前記の熱ラジカル重合の場合の記述と同様である。なお、該加熱時間中の加熱温度を変化させて好ましいラジカル重合を設計することも可能である。例えば、加熱初期は４０〜９０℃程度の比較的低温で加熱することにより重合性成分の揮発を防ぎながらラジカル重合を徐々に進行させ、次いで９０〜１８０℃程度の高温でラジカル重合を急速に進行させる、といった反応設計が考えられる。
【００６５】
いずれの加熱処理においても、望ましくない空気酸化や加水分解等の副反応を抑制するために、乾燥した窒素等不活性ガスあるいは乾燥空気の雰囲気とすることが好ましい場合がある。また、印刷の生産性を向上させる目的で、連続印刷ラインにおいて前記の加熱処理や光照射を複数回印加することも可能である。あるいは、印刷物を任意の温度で加熱保存する熱アニール工程を印刷工程の後に付加してラジカル重合を進行あるいは完結させることも可能である。
【００６６】
＜偽造検出印刷等の用途＞
本発明の印刷用インクは、蛍光体として使用する有機ランタノイド錯体の優れた輝度と色純度を保持し、対環境安全性に優れた水性溶媒（例えば水や含水エタノール等）を媒体とすることも可能であり、しかも沈殿を生じにくい長期保存安定性に優れたものである。また、汎用の水銀灯が発生する紫外線により励起され、しかも該励起波長と発光波長とが大きく隔たることを特徴とする。
【００６７】
近年の印刷・複写技術の進歩により、紙幣、クレジットカードや銀行等金融機関のキャッシュカード等の各種マネーカード類、身分証明書、パスポート等複製防止の必要のある印刷物の偽造の増加が懸念される。また、前記の各種マネーカード類は、電子マネー等今後の個人のインターネット取引急増から、その発行数の急増とそれに伴うカード偽造対策の必要性が論じられていることは衆知である。
【００６８】
かかる印刷物に本発明の印刷用インクを使用すると、該印刷物の真偽を極めて簡便に検査できる。例えば、携帯水銀灯の照射により本発明の印刷用インクが発生する高強度の可視蛍光により容易に目視検出可能である。これは、増感効果により高輝度発光する有機ランタノイド錯体の特性である、▲１▼紫外線により励起される性質、及び、▲２▼励起波長と発光波長とが大きく隔たる、という２つの性質から、太陽光や汎用照明器具等の紫外線含量の少ない日常の照明条件では発光が目視確認できる強度で実質的に起こらず、しかし特定波長の紫外線の照射条件で初めて目視確認可能な強度で発光するという原理による。従って、本発明の印刷用インクは、それが含有する有機ランタノイド錯体の蛍光能に由来する励起波長と発光波長の差が大きいことが望ましい。
【００６９】
Ｔｂ³⁺やＥｕ³⁺等の３価ランタノイド陽イオンの有機錯体は、特有のｆ軌道電子の遷移による蛍光の特徴として、通常、その発光帯の半値幅が数１０ｎｍ程度と狭くかつ配位子を変更しても発光帯のピーク波長がほとんど変動しないという特性を有する。一方、励起波長については、有機ランタノイド錯体の与える励起スペクトルの範囲の任意の波長で発光が可能なので、必要に応じてこの範囲の任意波長を励起波長と定めることができる。従って、前記した本発明の印刷用インクの励起波長と発光波長の差は、該インクが含有する有機ランタノイド錯体の主発光帯（即ち、最大輝度を与える発光帯）のピーク波長λemと、励起スペクトル範囲内の任意の励起波長λexとの差（λem−λex）として通常５０ｎｍ以上、好ましくは１００ｎｍ以上、更に好ましくは１５０ｎｍ以上、最も好ましくは２００ｎｍ以上となるように設計する。
【００７０】
また、例えば、緑色発光するＴｂ³⁺と赤色発光するＥｕ³⁺のような異種ランタノイド陽イオンの有機錯体を例にとると、それぞれが、固有の発光波長と狭い半値幅を有する複数の発光帯を有するため、これら以外の同色発光材料により仮に偽造印刷したとしても、その発光スペクトルの測定によりあたかも指紋による個人の特定のように容易に識別可能である。さらに、こうした異種の有機ランタノイド錯体を含有する複数種の本発明の印刷用インクの併用により、更に複雑な印刷パターン形成が可能であり、偽造防止に役立つ。
【００７１】
かかる概念による偽造困難な複雑な印刷パターン形成を意図する場合、複数種の有機ランタノイド錯体を任意の配合比で混合して本発明の印刷用インクに使用しても構わない。また精密な印刷を行うためには、インクジェット方式等、微細印刷に適した手段が好適である。
＜樹脂成形体＞
本発明の印刷用インクを使用した印刷面を有する樹脂成形体は前記の特徴により有用であり、例えば、偽造が困難な各種カード類（クレジットカード、キャッシュカード、ＩＤカード等）として好適に利用される。但し、かかるカード類の形状は一例にすぎず、本発明の樹脂成形体の形状に制限はない。可能な実用形状としては、前記のカード類の他、ＰＥＴボトル等のボトル状、ＯＨＰシート等のシート状、コンパクトカセットテープやビデオカセットテープ等の箱形成形体状、コンパクトディスク等のディスク状、光ファイバや釣り糸等の繊維状、樹脂ビーズ等の球状、農業用フィルムや食品包装用フィルム等のフィルム状等が例示できる。
【００７２】
該印刷面に定着された本発明の印刷用インク由来の印刷層の形状や厚さには制限はないが、該印刷層の厚さはその力学的強度や印刷効果の点で、通常０．１〜５０００μｍ、好ましくは１〜１０００μｍ、更に好ましくは０．８〜５００μｍ、最も好ましくは０．５〜２００μｍ程度とする。なお、本発明の樹脂成形体においては、本発明の印刷用インクの必須成分である前記の有機ランタノイド錯体が該樹脂成形体の印刷面において蛍光能を発揮することが必要条件であるので、該錯体は必ずしも該印刷面上に全て存在している必要はなく、その一部又は全部が印刷面の樹脂表層内部に浸透して存在しても構わない。かかる印刷面の樹脂表層内部への有機ランタノイド錯体の浸透深さに制限はないが、励起光照射時の蛍光能の点で通常１０ｍｍ以下、好ましくは７ｍｍ以下、更に好ましくは４ｍｍ以下、最も好ましくは１ｍｍ以下に制御する。
【００７３】
本発明の樹脂成形体に使用される樹脂には制限はないが、例えば、ポリエチレン樹脂やポリプロピレン樹脂等のポリオレフィン類、ポリ塩化ビニル等のＰＶＣ樹脂類、ポリ塩化ビニリデン等のＰＶＤＣ樹脂類、ポリスチレン樹脂、スチレン−アクリロニトリル共重合体（通称ＳＡＮ）、アクリロニトリル−ブタジエン−スチレン共重合体（通称ＡＢＳ）、アクリルゴムにアクリロニトリル−スチレン共重合体がグラフトした通称ＡＡＳ樹脂、ＥＰＤＭ（エチレン−ジエンモノマー共重合体）ゴムにアクリロニトリル−スチレン共重合体がグラフトした通称ＥＡＳ樹脂、ハイインパクトポリスチレン樹脂（通称ＨＩＰＳ）、シンジオタクティックポリスチレン樹脂等のスチレン系樹脂、ポリメチルメタクリレート樹脂（通称ＰＭＭＡ）等のアクリル樹脂、エチレン−ビニルアルコール共重合体（通称ＥＶＡＬ）等のポバール樹脂類、熱可塑性ポリウレタン樹脂等の熱可塑性樹脂類、ポリエチレンテレフタレート樹脂（通称ＰＥＴ）、ポリブチレンテレフタレート樹脂（通称ＰＢＴ）、ポリエチレンナフタレート樹脂（通称ＰＥＮ）等の芳香族ポリエステル樹脂、ポリオキシメチレン樹脂（通称ＰＯＭ）、ナイロン６、ナイロン６６、ナイロン４６、ナイロン１１、ナイロン１２、ナイロン６１０、ナイロン６１２、テレフタル酸および／またはイソフタル酸とヘキサメチレンジアミンとから得られるポリアミド、テレフタル酸および／またはイソフタル酸とアジピン酸とヘキサメチレンジアミンとから得られるポリアミド、共重合成分として１，３−フェニレンジオキシジ酢酸を含む共重合ポリアミド、共重合成分として二量体化脂肪酸を含む共重合ポリアミド等のポリアミド樹脂、ビスフェノールＡポリカーボネート等の芳香族ポリカーボネート樹脂（通称ＰＣ）、ポリ（２，６−ジメチルフェノール）等のポリフェニレンエーテル樹脂（通称ＰＰＥ）、ポリフェニレンスルフィド樹脂（通称ＰＰＳ）、フッ素樹脂等のポリアリーレンスルフィド樹脂等の熱可塑性エンジニアリングプラスチック（いわゆるエンプラ）類、ポリスルホン樹脂（通称ＰＳＵ）、ポリエーテルスルホン樹脂（通称ＰＥＳ）、ポリアリレート樹脂（通称ＰＡＲ）、ポリイミド樹脂（通称ＰＩ）、ポリエーテルエーテルケトン樹脂（通称ＰＥＥＫ）、液晶ポリマー（通称ＬＣＰ）等のいわゆるスーパーエンプラ類、不飽和ポリエステル樹脂、エポキシ樹脂、フェノール樹脂、ユリア（尿素）樹脂、メラミン樹脂、ジアリルフタレート樹脂、シリコーン樹脂等の硬化性樹脂等が例示される。これらのうち、経済性、剛性や靱性等機械的物性、成形性、生産性等のバランスの点では、ポリプロピレン樹脂、ポリ塩化ビニル脂類、ＳＡＮ樹脂、ＡＢＳ樹脂、ＰＭＭＡ樹脂、ＰＣ樹脂、ＰＥＴ樹脂等の熱可塑性樹脂が好適である。
【００７４】
これらの樹脂は、複数をブレンドしたいわゆるポリマーアロイ材料として用いても構わない。また任意の添加剤、例えば酸化防止剤、熱安定剤、あるいは光安定剤等の安定剤類、ガラス繊維、ガラスビーズ、マイカ、タルク、カオリン、粘土鉱物、炭素繊維、カーボンブラック、黒鉛、金属繊維、金属粉等のフィラー類、帯電防止剤、離型剤、可塑剤、紫外線吸収剤等の添加剤類、顔料や染料等の着色剤類、ゴムやエラストマー等の耐衝撃性付与剤等必要に応じて任意の添加物を混合することも可能である。
【００７５】
本発明の樹脂成形体を得るに当たり、印刷前の印刷面に、あらかじめ任意の表面処理（例えばプラズマ処理、コロナ処理、オゾン処理、裸火処理、酸やアルカリ処理等の酸化反応等の化学反応を施す処理、各種プライマーを塗布して接着層を設ける処理、吸水処理、微細な擦過傷をつける摩擦処理、等）を行うことも可能である。
【００７６】
【実施例】
以下に、実施例により本発明の具体的態様を更に詳細に説明するが、本発明は、その要旨を越えない限り、これらの実施例によって限定されるものではない。［測定装置と条件等］
（１）ＮＭＲ：日本電子社製ＪＮＭ−ＥＸ２７０型ＦＴ−ＮＭＲ（¹Ｈ：３００ＭＨｚ）溶媒：ＣＤＣｌ₃ 。
（２）ＦＴ−ＩＲ：日本分光工業社製ＦＴ／ＩＲ−８０００型ＦＴ−ＩＲを使用し、非晶性物質はＫＢｒ法あるいは液膜法（食塩結晶上にサンプルの塩化メチレン溶液のキャストフィルムを作成）にて、結晶性物質はＫＢｒディスク法でそれぞれ測定した。
（３）蛍光スペクトル：日立製作所社製Ｆ−３０００型蛍光光度計を使用して室温大気下で測定した。
【００７７】
［合成例と実施例］
合成例１：第１世代デンドロンを配位子とする有機Ｔb³⁺錯体の合成
前掲のＭ．Ｋａｗａら著の文献において、フォーカルポイント部分の原料である３，５−ジヒドロキシ安息香酸の代わりに、３，４−ジヒドロキシ安息香酸（以下、３４ＤＨＢＥｔと略記）を用いて同様の合成を行い、第１世代のポリベンジルエーテル構造のカルボン酸デンドロンを合成した（［３４Ｇ１］ＣＯＯＨと略記）。即ち、３４ＤＨＢＥｔ（１当量）、ベンジルブロミド（２．０５当量）、１８−クラウン−６−エーテル（０．２当量）、及び無水炭酸カリウム（直前に乳鉢で粉砕、２．５当量）をアセトン中で加熱還流するエーテル化反応によりデンドロン骨格を構築し、次いで、該エチルエステル基に対して３当量の水酸化カリウムを含むＴＨＦ／メタノール含水溶液中で加水分解し、更に塩酸で中和した後再結晶で精製する手順によった。この生成物は、ＦＴ−ＩＲスペクトルにおいて１６８０ｃｍ^-1付近のカルボン酸のカルボニル基に帰属される吸収と、同じくカルボキシル基に帰属されるＯ−Ｈ伸縮振動とを与え、また¹Ｈ−ＮＭＲスペクトルにて、末端フェニル基（１０プロトン）、ベンジル基（２種、合計４プロトン）、及び分岐点であるベンゼン環（３プロトン）に帰属されるシグナルを与えたことからその構造を確認した。こうして得た［３４Ｇ１］ＣＯＯＨ（３当量）を酢酸テルビウム（ＩＩＩ）無水塩（１当量）と混合し、クロロベンゼン中で加熱還流、次いで溶媒とともに生成する酢酸を減圧留去して、［３４Ｇ１］ＣＯＯＨのカルボキシレートを配位子とする有機Ｔｂ³⁺錯体（［３４Ｇ１］₃Ｔｂと略記）を調製した。この生成物は、ＦＴ−ＩＲスペクトルにおいて１６８０ｃｍ^-1付近のカルボン酸のカルボニル基に帰属される吸収と、同じくカルボキシル基に帰属されるＯ−Ｈ伸縮振動とを与えないことから、原料カルボン酸である［３４Ｇ１］ＣＯＯＨが相当するカルボキシレートに変換されＴｂ³⁺錯体を形成したものと考えられた。［３４Ｇ１］₃Ｔｂの一部は乳鉢で細かく粉砕して、以下の実施例に用いた。
【００７８】
合成例２：第２世代デンドロンを配位子とする有機Ｔb³⁺錯体の合成
合成例１のデンドリマー合成戦略により、相当する第２世代のカルボン酸デンドロンを合成した（［３４Ｇ２］ＣＯＯＨと略記）。即ち、合成例１において、ベンジルブロミドの代わりに東京化成（株）から供給される３，５−ジベンジルオキシベンジルブロミドを用いて以下同様の合成操作を行った。この生成物は、ＦＴ−ＩＲスペクトルにおいて１６８０ｃｍ^-1付近のカルボン酸のカルボニル基に帰属される吸収と、同じくカルボキシル基に帰属されるＯ−Ｈ伸縮振動とを与え、また¹Ｈ−ＮＭＲスペクトルにて、末端フェニル基（２０プロトン）、ベンジル基（３種；４プロトン、２プロトン、２プロトン）、及び分岐点である３つのベンゼン環（合計９プロトン）に帰属されるシグナルを与えたことからその構造を確認した。こうして得た［３４Ｇ２］ＣＯＯＨを、合成例１における［３４Ｇ１］ＣＯＯＨの代わりに用いて同様の操作を行い、［３４Ｇ２］ＣＯＯＨのカルボキシレートを配位子とする有機Ｔｂ³⁺錯体（［３４Ｇ２］₃Ｔｂと略記）を調製した。この生成物は、ＦＴ−ＩＲスペクトルにおいて１６８０ｃｍ^-1付近のカルボン酸のカルボニル基に帰属される吸収と、同じくカルボキシル基に帰属されるＯ−Ｈ伸縮振動とを与えないことから、原料カルボン酸である［３４Ｇ２］ＣＯＯＨが相当するカルボキシレートに変換されＴｂ³⁺錯体を形成したものと考えられた。
【００７９】
合成例３：ナフタレン誘導体を配位子とする有機Ｅｕ³⁺錯体の合成
前記のＪ．Ｙｕａｎら著の文献等で公知の方法によりＥｕ（ＮＴＡ）₃（構造は前記式１０参照）を合成した。即ち、４，４，４−トリフルオロ−１−（２−ナフチル）−１，３−ブタンジオン（４．２７ｇ；３当量）をエタノール（３８ｍＬ）、メタノール（１８ｍＬ）、及び水（１ｍＬ）の混合溶媒に室温で溶解し、電動モーター動力の機械的攪拌翼により攪拌した。この黄色い溶液に２８％アンモニア水（０．９７ｇ；３当量）を加え、更に、別途調製した塩化ユウロピウム６水和物（１．９６ｇ；１当量）を水（６４ｍＬ）に溶解した水溶液を１時間かけて滴下し、粘度の高い析出物を得た。濃縮して得た残渣をアセトンに溶解し、不溶物を濾別して得たアセトン溶液を大量の氷水中に激しい攪拌とともに投入した。得られた析出物を濾別して十分に水洗して、目的とするＥｕ（ＮＴＡ）₃を得た。
【００８０】
合成例４：ラジカル重合性を有する第１世代デンドロンを配位子とする有機Ｔb³⁺錯体の合成
４−ビニルベンジルクロリド（Ａｌｄｒｉｃｈ社製、１．０当量）、３，４−ジヒドロキシ安息香酸エチル（１．０当量）、無水炭酸カリウム（２．５当量）、１８−クラウン−６エーテル（０．２当量）、テトラエチルアンモニウムブロミド（１．０当量）を乾燥アセトンに加え、更に触媒量の２，６−ジ−ｔｅｒｔ−ブチル−４−メチルフェノールを加えて６０℃で加熱攪拌した。市販のシリカゲル薄層クロマトグラフィ（ＴＬＣ）で反応をモニターし、４−ビニルベンジルクロリドの消失を確認した後、ベンジルブロミド（１．０当量）を加えて更に反応を継続した。ＴＬＣでベンジルブロミドの消失を確認した後、濃縮した。残渣は、塩化メチレンと水の２相間で分液し、有機相を濃縮して粗生成物を得た。これをシリカゲルカラムクロマトグラフィ（ｎ−ヘキサン／酢酸エチル系）で精製し、３，４−ジオキシ安息香酸残基にビニルベンジル基とベンジル基をそれぞれ１つずつエーテル結合した第１世代のエステルデンドロン（以下、Ｖ［３４Ｇ１］ＣＯＯＥｔと略）を得た。この構造は、ＦＴ−ＩＲスペクトルにおいて１７１０ｃｍ^-1付近にエステル基のカルボニル基に由来する吸収帯が観測されこと、及び、¹Ｈ−ＮＭＲスペクトルにおいてエトキシ基のメチル基（トリプレット／３Ｈ）とメチレン基（カルテット／２Ｈ）、ベンジル位プロトン（４Ｈ）、３種のビニル基プロトン（ダブレット／１Ｈ、ダブルダブレット／１Ｈ、及びダブルダブレット／１Ｈ）、芳香族プロトン（１Ｈ、９Ｈ、及び２Ｈ）のそれぞれのシグナルが観測されたことから確認した。以下、合成例１同様の加水分解次いで塩酸による中和操作により相当するカルボン酸デンドロンに変換した。こうして得た第１世代のカルボン酸デンドロン（以下、Ｖ［３４Ｇ１］ＣＯＯＨと略記）の構造は、ＦＴ−ＩＲスペクトルにてカルボキシル基に帰属されるカルボニル基の吸収帯が観測されたこと、及び¹Ｈ−ＮＭＲにおいてエトキシ基に帰属されるシグナルが見られなかったことから確認した。こうして得たＶ［３４Ｇ１］ＣＯＯＨを、合成例１において［３４Ｇ１］ＣＯＯＨの代わりに用いて同様の操作を行い、Ｖ［３４Ｇ１］ＣＯＯＨのカルボキシレートを配位子とする有機Ｔｂ³⁺錯体（Ｖ［３４Ｇ１］₃Ｔｂと略記）を調製した。この生成物は、ＦＴ−ＩＲスペクトルにおいてカルボン酸のカルボニル基に帰属される吸収と、同じくカルボキシル基に帰属されるＯ−Ｈ伸縮振動とを与えないことから、原料カルボン酸であるＶ［３４Ｇ１］ＣＯＯＨが相当するカルボキシレートに変換されＴｂ³⁺錯体を形成したものと考えられた。
【００８１】
＜水性懸濁液の調製＞
合成例５：デンドロンを配位子とする有機Ｔb³⁺錯体の水性懸濁液
水（９９．５ｇ）にドデシルベンゼンスルホン酸ナトリウム（以下ＳＤＳと略記、０．２ｇ）を溶解し、ここに合成例１で得た有機Ｔb³⁺錯体［３４Ｇ１］₃Ｔｂの粉砕粉末（数平均粒径は約５μｍ、０．３ｇ）を加えて、室温で緩やかに攪拌した。攪拌を継続しながらＳＤＳ（０．３ｇ）を更に加え、次いで前記の［３４Ｇ１］₃Ｔｂの粉砕粉末（０．２ｇ）を更に加えた。この水性分散液をガラス瓶に密栓して、激しく振り混ぜた後、直ちに吉田機械興業（株）製ナノマイザーＹＳＮＭ１５００−５超微粒化卓上実験装置（力学的破砕を行うジェネレータの方式は「衝突型ジェネレータ」とした；例えば特許第２７８８０１０号を参照）の原料液投入口に加え、高圧での衝突力による力学的破砕を行った。この時、水性分散液に印可した圧力１３０メガパスカルとし、該装置を１回通過させた。その結果、室温で静置しても少なくとも４５日間沈殿を生じない程度に該有機Ｔb^{3 +}錯体が懸濁安定化された水性懸濁液を得た。この水性懸濁液は、３６５ｎｍ波長の汎用水銀灯が発する紫外線を照射すると該Ｔb³⁺錯体特有の明るい緑色の蛍光を与えた。この水性懸濁液の蛍光スペクトルを、励起波長を３００ｎｍとして光路長１ｃｍの石英セル中で測定したところ、５４２ｎｍ付近の主発光帯を始めとするＴb³⁺陽イオンに固有のものであり主発光帯の半値幅が１７ｎｍ程度である色純度の良いものであることが確認された。
【００８２】
合成例６：ナフタレン誘導体を配位子とする有機Ｅｕ³⁺錯体の水性懸濁液
合成例５において、有機Ｔb³⁺錯体［３４Ｇ１］₃Ｔｂの粉砕粉末の代わりに、合成例３で得たナフタレン誘導体を配位子とする有機Ｅｕ³⁺錯体Ｅｕ（ＮＴＡ）₃の粉砕粉末（数平均粒径は約５μｍ）を用いた他は同様の操作を行うと、室温で静置しても沈殿を生じない程度に該有機Ｅｕ³⁺錯体が懸濁安定化された水性懸濁液を得る。この水性懸濁液は、３６５ｎｍ波長の汎用水銀灯が発する紫外線を照射すると該Ｅｕ³⁺錯体特有の明るい赤い蛍光を与え、この水性懸濁液の蛍光スペクトルを、励起波長を３００ｎｍとして合成例５同様に測定すると、６１２ｎｍ付近の主発光帯を始めとするＥｕ³⁺陽イオンに固有のものであり主発光帯の半値幅が数１０ｎｍと狭い色純度の良いものであることが確認される。
【００８３】
実施例１：有機Ｔb³⁺錯体を含有した水性懸濁液型インク
合成例５で得た蛍光性水性懸濁液を１／４容量まで濃縮し、ここに平均分子量が３０万であるポリエチレンオキシド（以下ＰＥＯと略記、該濃縮液中で２重量％となる量）を溶解して水性懸濁液型インクを得た。これを紙に塗布して乾燥したところ、定着性が良好でかつ合成例５で説明したと同一の緑色の蛍光能を有する印刷面を得た。
【００８４】
実施例２：有機Ｅｕ³⁺錯体を含有した水性懸濁液型インク
実施例１において、蛍光性水性懸濁液として合成例６で得るものを使用した他は同一の操作を行うと、定着性が良好でかつ合成例６で説明したと同一の赤色の蛍光能を有する印刷面を得る。
実施例３：有機Ｔb³⁺錯体を含有した溶液型インク
合成例２で得た第２世代デンドロンを配位子とする有機Ｔb³⁺錯体［３４Ｇ２］₃Ｔｂ（２０重量部）をＴＨＦ／トルエン混合溶媒（重量混合比＝８０／２０；８０重量部）に溶解して溶液型インクを得た。これを９０℃に加熱したポリメチルメタクリレート（ＰＭＭＡ）樹脂板上に噴霧塗布して熱風乾燥させ、定着性が良好な印刷面を得た。この印刷面は、３６５ｎｍ波長の汎用水銀灯が発する紫外線を照射すると該Ｔb³⁺錯体特有の明るい緑色の蛍光を与えた。この印刷面の蛍光スペクトルを、励起波長を３００ｎｍとして測定すると、５４２ｎｍ付近の主発光帯を始めとするＴb³⁺陽イオンに固有のものであり主発光帯の半値幅が２０ｎｍ程度である色純度の良いものであることが確認された。
【００８５】
実施例４：有機Ｔb³⁺錯体を含有した重合性溶液型インク
実施例３で使用した有機Ｔb³⁺錯体（［３４Ｇ２］₃Ｔｂ、５重量部）、ベンジルアクリレート（４５重量部）、及びＡＩＢＮ（１重量部）を実施例３で使用したＴＨＦ／トルエン混合溶媒（４９重量部）に溶解して溶液型インクを得る。これを９０℃に加熱したポリエチレンテレフタレート（ＰＥＴ）樹脂成形体上に噴霧塗布し、９０℃の窒素気流オーブン中で加熱定着させると、定着性が良好な印刷面を得る。この印刷面は、実施例３で説明したと同様の緑色の蛍光能を有する。
【００８６】
実施例５：重合性有機Ｔb³⁺錯体を含有した重合性溶液型インク
合成例４で得た重合性有機Ｔb³⁺錯体Ｖ［３４Ｇ１］₃Ｔｂ（１０重量部）、ベンジルアクリレート（４０重量部）、及びＡＩＢＮ（１重量部）を実施例３で使用したＴＨＦ／トルエン混合溶媒（４９重量部）に溶解して溶液型インクを得る。これを実施例４同様の操作でＰＥＴ樹脂成形体上に噴霧塗布、次いで加熱定着させると良好な印刷面を得る。この印刷面は、３６５ｎｍ波長の汎用水銀灯が発する紫外線を照射すると該Ｔb³⁺錯体特有の明るい緑色の蛍光を与え、この印刷面の蛍光スペクトルを励起波長を３００ｎｍとして測定すると、５４２ｎｍ付近の主発光帯を始めとするＴb³⁺陽イオンに固有のものであり主発光帯の半値幅が２０ｎｍ程度である色純度の良いものであることが確認される。
【００８７】
【発明の効果】
本発明の印刷用インクは有機ランタノイド錯体を含有するので優れた輝度と色純度を有する。また該錯体が溶解状態、あるいは微粒子として懸濁安定化された状態にあるので実質的に沈殿を生成しない長期保存安定性に優れ、しかも水性溶媒を使用すれば対環境安全性に優れたものとなる。また、汎用の水銀灯による３６５ｎｍ波長の紫外線励起で発光し、しかも該励起波長と発光波長とが大きく隔たることを特徴とするので、例えばマネーカードや紙幣など複製防止の必要のある印刷物の真偽を携帯水銀灯の照射で容易に目視検出する偽造検出印刷等、蛍光を利用する各種印刷用途に有用である。
【図面の簡単な説明】
【図１】 デンドリマーの世代とフォーカルポイントを表す模式図である。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a printing ink having fluorescence. Since the printing ink of the present invention contains an organic lanthanoid complex, it has excellent brightness and color purity, is excellent in long-term storage stability, and is excellent in environmental safety if an aqueous solvent is used. Further, since it emits light by ultraviolet excitation by a general-purpose mercury lamp, and the excitation wavelength and the emission wavelength are largely separated from each other, for example, the authenticity of a printed matter that needs to be prevented from being copied such as a money card or a banknote is indicated by a portable mercury lamp. It is useful for various printing applications using fluorescence, such as counterfeit detection printing that is easily visually detected by irradiation.
[0002]
[Prior art]
A lanthanoid cation is a light-emitting substance characterized by a narrow wavelength fluorescence based on a characteristic f-orbital electron transition and a long fluorescence lifetime of milliseconds. A narrow emission band wavelength means that it is practically a light emitting material with good color purity. Due to these features, fluorescent lanthanoid complexes are used as luminescent reagents in biological analysis such as fluorescence immunoassay and cell markers.
[0003]
The lanthanoid cation is sensitized by an organic ligand having an aromatic ring and acquires high fluorescence ability. Yuan et al .; Analytical Sciences February 1996, 12, page 31 (1996). In particular, in a lanthanoid trivalent cation complex having a polybenzyl ether dendron as a ligand, the dendron has Tb³⁺And Eu³⁺The “antenna effect” means that the fluorescent ability is greatly enhanced by sensitizing the above and the like very strongly. Kawa et al .; Chem. Mater. 10, page 286 (1998). Sensitization by such an organic ligand usually occurs by a mechanism in which ultraviolet light is absorbed by the organic ligand, and then fluorescence is generated in the visible to near-infrared wavelength region by transferring the energy of the ultraviolet light to the lanthanoid cation. .
[0004]
Luminescent fine particles having such a characteristic luminous ability in a particulate object are generally of great interest in applications such as suspensions in which they are suspended. Various compositions have been proposed to take advantage of the ability. For example. Okamoto et al .; Macromolecules, Vol. 14, p. 17 (1981), a method of copolymerizing or dispersing in a synthetic resin matrix, T. et al. Jin et al. Alloys Compd. 252, page 59 (1997), a method of dispersing in a glass matrix, or fixation to a polymer latex that has been put to practical use as a fluorescent immunoassay reagent (for example, Japanese Patent Publication No. 1-59546, No. 61-128168, Japanese Patent Laid-Open No. 3-188374, or German Publication No. 2628158). However, none of these techniques can be said to exhibit its fluorescence ability to the maximum because the organic lanthanoid complex is diluted in principle by the matrix substance.
[0005]
On the other hand, inorganic phosphors doped with lanthanoid elements are widely used as fluorescent materials for cathode ray tubes of television receivers. However, such inorganic phosphors are stably suspended in water or organic solvents without causing precipitation. It was difficult.
[0006]
[Problems to be solved by the invention]
The present invention has been made in view of the above circumstances, and its purpose is to have fluorescence ability, in particular, fluorescence ability with good color purity in which the excitation wavelength and fluorescence wavelength are largely separated, and to substantially precipitate the precipitate by standing. The present invention provides a printing ink excellent in long-term storage stability that does not occur in the method, a printing method using the printing ink, and a resin molded body having a printing surface using the printing ink.
[0007]
[Means for Solving the Problems]
In view of the above situation, the present inventor has conducted extensive systematic studies on a method for dissolving or suspending a fluorescent organic lanthanoid complex itself in a solvent in a very stable manner. As a result, in particular, a lanthanoid having an aromatic dendron as a ligand. The complex itself has extremely high brightness and excellent solubility in organic solvents, and the organic lanthanoid complex is suspended in water in the presence of a surfactant by mechanically crushing the organic lanthanoid complex with impact force, so that the complex itself is suspended very stably. In addition, it is possible to improve the printing quality such as printing durability by obtaining an aqueous suspension that retains luminous ability and further polymerizing the polymerizable component such as radical polymerization in the printing ink. The present invention has been found.
[0008]
  That is, the gist of the present invention is as follows.
(1) Printing ink containing an organic lanthanoid complexAnd the organic lanthanoid complex contains an aromatic dendron having an aromatic polyether as a ligand as a ligand.,
(2) The method for producing a printing ink as described above, wherein the organic lanthanoid complex dispersed in an aqueous solvent is suspended and stabilized by mechanical pulverization in the presence of a surfactant;
(3) A printing method comprising a step of polymerizing a polymerizable component in the printing ink, and
(4) having a printing surface using the printing ink.It is characterized byResin moldings,
There are 4 points.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in more detail.
<Ink for printing>
The printing ink of the present invention contains an organic lanthanoid complex as a fluorescent species, and the complex is in a dissolved state or a suspension-stabilized state in which precipitation upon standing does not substantially occur.
[0010]
In the present invention, the “suspended” state means the physicochemical action of molecules in which the fine particles (solid phase) are present in the aqueous solvent phase (liquid phase) (for example, thermal motion of the molecule, solvent). It means a state in which no precipitating coarse particles are generated by gravity due to the sum effect, micelle formation ability, etc. Therefore, even if the presence of the fine particles is confirmed visually or microscopically, the dispersed state in which the fine particles are settled by gravity and do not cause precipitation by standing is nothing but the suspended state referred to here.
[0011]
The “suspension stabilization” in the present invention means that no precipitation due to gravity is generated within 48 hours from the state of being sufficiently stirred under a room temperature standing condition around 23 ° C.
The aqueous suspension preferably used for the printing ink of the present invention suspended and stabilized by a surfactant as described later is used under chemically severe storage conditions (for example, extremely high temperatures such as 60 ° C. or higher, direct irradiation). If exposure to light such as sunlight, mixing of acid or alkali, etc.) is avoided, the precipitate does not substantially form, and the time during which no precipitate is formed under the above-mentioned standing conditions is specifically preferably 168 hours. (7 days) or more, more preferably 740 hours (about 1 month) or more, more preferably 4400 hours (about half a year) or more, and most preferably 8800 hours (about 1 year) or more. A suspension that precipitates within 48 hours under the standing conditions is not practically excellent in storage stability, and thus does not meet the object of the present invention.
[0012]
As long as the achievement of the object of the present invention is not significantly impaired, the aqueous suspension of the present invention contains optional additives, for example, stabilizers such as antioxidants, heat stabilizers, or light stabilizers, glass fibers, and glass beads. , Mica, talc, kaolin, clay minerals, carbon fibers, carbon black, graphite, metal fibers, metal powders and other fillers, colorants, UV absorbers, viscosity modifiers, adhesives that improve adhesion to substrates, etc. These additives, impact imparting agents such as rubber and elastomer, thermoplastic resins and the like can be mixed as required. Hereinafter, explanations will be added for main additives.
[0013]
When the printing ink of the present invention uses an aqueous solvent, an appropriate water-soluble polymer may be added for the purpose of adjusting viscosity and improving moisture retention. Such water-soluble polymers include polyethylene oxide, polypropylene oxide, ethylene oxide-propylene oxide copolymer, glycerin-based polyoxyethyleneoxypropylene triol (that is, three block copolymers of ethylene oxide and propylene oxide block copolymer and glycerin). A hydroxyl group ether-bonded, or a copolymer in which the copolymer is a random copolymer), a vinyl acetal resin (produced by reacting polyvinyl alcohol with a lower aldehyde such as formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde, Vinyl acetate, polyvinyl acetal, and polyvinyl alcohol have a composition in which they are randomly arranged), and a plurality of these may be used in combination. The amount of the water-soluble polymer added is usually about 0.1 to 15% by weight in the printing ink of the present invention.
[0014]
Either a pigment or a dye can be used as the colorant added to the printing ink of the present invention. As the pigment, known organic pigments or inorganic pigments can be used alone or in combination. For example, azo, phthalocyanine, quinacridone, anthraquinone, dioxazine, indigo / thioindigo, berylone / berylene, Organic pigments such as indolenone and azomethylene azo, and inorganic pigments such as carbon black, mica, titanium white, pearl pigments, metal pigments such as iron oxide, aluminum powder, and brass can be used. These pigments are usually polyacrylic acid, polymethacrylic acid, styrene-acrylic acid copolymer, styrene-maleic anhydride copolymer, and their metal salts, ammonium salts, amine salts, etc., or other known ones. If it is kneaded into a resin or the like and used as a processed pigment, it may be convenient because it is easily dispersed when mixed with ink. Moreover, you may use the commercially available processed pigment which has already kneaded the pigment in the dispersing agent. These pigments can be used singly or in combination while taking the hue into consideration, and are usually added in an amount of about 1 to 30% by weight in the printing ink of the present invention. As the dye, known ones such as monoazo, disazo, metal complex type monoazo, anthraquinone, phthalocyanine, and triallylmethane may be added.
[0015]
In the printing ink of the present invention, an acrylic resin powder, an acrylic resin aqueous solution, an acrylic resin colloidal dispersion, an acrylic resin emulsion, an extender pigment, and the like can be blended as a thixotropic agent and a pigment dispersant.
A small amount of a glycol ether such as diethylene glycol monobutyl ether or triethylene glycol monobutyl ether may be added as a penetration aid when the printing ink of the present invention is applied to a hydrophilic substrate such as paper or wood.
[0016]
<Organic lanthanoid complex>
The organic lanthanoid complex used in the present invention is a complex comprising a lanthanoid cation and an organic ligand as constituent components. And it is desirable that it is a complex which shows the sensitizing action of this ligand (a phenomenon in which a lanthanoid cation emits light by the energy of light exciting the ligand).
[0017]
When the organic lanthanoid complex has solvent solubility, it is particularly suitable as a material for a solution-type ink described later. Examples of organic ligands excellent in solvent solubility include dendron described below.
In addition, when the crushed fine particles obtained by mechanical crushing described later emit light with high luminance, the complex is particularly suitable as a material for a suspension-type ink described later. It is particularly desirable that it has optical transparency. However, even in an organic lanthanoid complex with insufficient optical transparency, light emission is expected at least on the surface of the crushed fine particles, and therefore the fluorescent material can achieve the purpose of the suspension type ink of the present invention to some extent. Needless to say.
[0018]
The lanthanoid cation here is Ce.³⁺, Pr³⁺, Nd³⁺, Nd⁴⁺, Sm²⁺, Sm³⁺, Eu²⁺, Eu³⁺, Tb³⁺, Dy³⁺, Dy⁴⁺, Ho³⁺, Er³⁺, Tm²⁺, Tm³⁺, Yb²⁺, Yb³⁺Among others, Pr³⁺, Nd³⁺, Sm³⁺, Eu³⁺, Tb³⁺, Dy³⁺, Ho³⁺, Er³⁺, Tm³⁺, Yb³⁺The trivalent cation such as Sm is preferable because it emits fluorescence having characteristics such as visible to near infrared region, long life, narrow wavelength width, etc.³⁺, Eu³⁺, Tb³⁺, Dy³⁺, And Tm³⁺Is more preferred, and Eu³⁺And Tb³⁺Is most preferable in terms of emission intensity.
[0019]
On the other hand, the organic ligand mentioned here is a ligand containing a carbon atom, and its chemical structure is not particularly limited, but a carboxylate group or a β-diketonate group is coordinated in terms of sensitizing action. What has as a structure is suitable. There is no particular limitation on the combination of these ligands and lanthanoid cations, but in the present invention, a preferable combination from the viewpoint of light emission characteristics is Tb.³⁺And Eu³⁺Having a carboxylate group for Eu, and Eu³⁺And a ligand having a β-diketonate group. Other organic ligands or organic coordination structures include oxygen-containing functional groups such as hydroxyl groups, ketone groups, and ether groups, cyanate ions (CN^-), Nitrile groups, pyridine rings, triazine rings, amino groups and other nitrogen-containing functional groups, mercapto groups (or thiol groups: —SH), thiophene rings, thiocyanate ions (SCN)^-), Sulfur-containing functional groups such as thiocyanuric acid residues and the like.
[0020]
The organic lanthanoid complex used in the present invention includes inorganic ligands (eg, halide ions such as chloride ions and iodide ions, nitrate ions, sulfate ions, perchlorate ions, tetrafluoroborate ions, hexafluorophosphate ions, etc. However, the use of an inorganic ligand may be disadvantageous in terms of the luminous ability of the complex.
[0021]
<Preferred carboxylate type complex>
In view of solvent solubility and sensitizing effect, organic lanthanoid complexes suitable for the printing ink of the present invention include complexes containing dendron ligands. In particular, those having an aromatic dendron having a carboxylate group at the focal point and an aromatic ring as a repeating unit as a ligand are very suitable.
[0022]
The term “dendron” in the present invention is widely used in the meaning of a molecular building component having such a structural unit in the research of dendrimers (dendrimer: a general term for polymer structures having a dendritic regular branch) which has become popular recently. Which is the same as the terminology used, for example, G. R. Newkome et al .; Dendritic Molecules, Concepts, Synthesis, Perspectives (VCH VerlagsgesellschaftmbH; Weinheim, Germany; 1996, ISBN: 3-527-25625). Then, the starting point of the branch structure (corresponding to the core of the fan when the dendron is schematically considered as a fan shape) is referred to as a focal point, and the order of the branch is referred to as “generation” (FIG. 1). reference). The number of branches at the branch point of the dendron in the present invention is not limited, but is usually 2 (in the case of FIG. 1) or 3 and preferably 2 branches. In the present invention, a structure having one branch point (that is, the first generation) is also regarded as a dendron.
[0023]
The dendron used as the organic ligand in the present invention preferably has an aromatic ring in the repeating unit of its chemical structure. This is because the dendron exhibits the “antenna effect” by absorbing ultraviolet light or visible light. Here, the aromatic ring means, for example, a hydrocarbon aromatic ring such as a benzene ring, a naphthalene ring and an anthracene ring, a nitrogen-containing aromatic ring such as a pyridine ring and a quinoline ring, and the like. Specific examples of dendron structures suitable for the present invention include aromatic polyethers such as polybenzyl ether, aromatic polyesters such as polyhydroxybenzoic acid, aromatic or semi-aromatic polyamides, and aromatic polycarbonates (PC). , Aromatic polyester carbonate, aromatic polyketone, aromatic polyether ketone (PEK), aromatic polyether ether ketone (PEEK), aromatic polysulfide such as polyphenylene sulfide (PPS), aromatic polyimide, aromatic polyamideimide, etc. Aromatic polymer structures containing elements other than carbon in the polymer main chain, aromatic conjugated polymer structures in which the main chain is composed of carbon-carbon bonds such as polyphenylene, polyphenylene ethynylene, polyphenylene ethylene, etc. Of these, polybenzyl ether, etc. Aromatic polyethers such as aromatic polyethers and polyhydroxybenzoic acid are preferred, aromatic polyethers such as polybenzyl ether are more preferred, and structures having a 3,5-dioxybenzyl group as a repeating unit (C.J. Hawker et al .; see J. Chem. Soc., Chem. Commun., Pages 1010-1013 (1990)). Note that these multiple types of structures may coexist in one dendron as long as the light emission characteristics of the complex are not significantly impaired.
[0024]
Further, when the dendron has a 3,5-dioxybenzoate structure represented by the following formula (1) at its focal point, it is Tb in terms of light emission characteristics.³⁺And Eu³⁺In the case where it has a 3,4-dioxybenzoate structure represented by the following formula (2), Tb³⁺Is particularly suitable.
[0025]
[Chemical 1]

[0026]
[Chemical 2]

[0027]
The number of generations of such dendrons is not particularly limited, but usually 1 to 6 generations, preferably 1 to 4 generations (preferably 2 to 4 generations in terms of light emission effect) for ease of synthesis, ease of synthesis and light emission effect. From the balance, the first to third generations are most preferable.
As a specific structural example of the carboxylate complex suitable for the present invention, a polybenzyl ether dendron represented by the structural formula in which the substituents R are all hydrogen atoms in the following general formulas (3) to (8) is coordinated. Examples include lanthanoid complexes as children.
[0028]
[Chemical Formula 3]

[0029]
[Formula 4]

[0030]
[Chemical formula 5]

[0031]
[Chemical 6]

[0032]
[Chemical 7]

[0033]
[Chemical 8]

[0034]
However, Ln in the general formulas (3) to (5)³⁺Is Tb³⁺Or Eu³⁺In the general formulas (3) to (8), R represents a hydrogen atom or a vinyl group.
Among the examples where the substituents R are all hydrogen atoms in the general formulas (3) to (8), the second generation polybenzyl ether dendron carboxylate represented by the general formula (4) or (7) is a ligand. The complex represented by general formula (3) or (6) is a complex having a first-generation polybenzyl ether dendron carboxylate as a ligand as a complex. This is practically very useful in terms of luminance per unit weight.
[0035]
<Suitable β-diketonate type Eu³⁺Complex>
Eu suitable for the printing ink of the present invention³⁺And a fluorescent organic lanthanoid complex composed of a ligand having a β-diketonate group is represented by the following general formula (9).
[0036]
[Chemical 9]

[0037]
In the general formula (9), R represents an alkyl group having 6 or less carbon atoms or a fluorinated alkyl group having 6 or less carbon atoms, and R ′ represents an aromatic group. Suitable examples of R include straight chain alkyl groups such as a methyl group, ethyl group, n-butyl group and n-hexyl group, branched alkyl groups such as isopropyl group and isobutyl group, trifluoromethyl group, and pentafluoroethyl. Groups, linear perfluoroalkyl groups such as heptafluoropropyl group and nonafluorobutyl group, and perfluoroalkyl groups having a branch such as heptafluoroisopropyl group and nonafluoroisobutyl group, etc., and more preferable is trifluoromethyl. Group, a linear perfluoroalkyl group such as a pentafluoroethyl group, a heptafluoropropyl group and a nonafluorobutyl group, and a perfluoroalkyl group having 4 or less carbon atoms such as a heptafluoroisopropyl group, more preferably a trifluoromethyl group , Pentafluoroethyl group, heptaful Ropuropiru perfluoroalkyl group having 3 or less carbon atoms such as groups, the most preferred is trifluoromethyl group. On the other hand, preferred R ′ is an aromatic hydrocarbon group such as a phenyl group, a naphthyl group, an anthracenyl group or a pyrenyl group, a sulfur atom such as a thienyl group (or a tenoyl group) or a furanyl group (or a furoyl group) or an oxygen atom. An aromatic group containing a hetero atom such as, for example, is preferable. Among them, a phenyl group or a naphthyl group is more preferable, and a naphthyl group is most preferable. Therefore, specific structural examples suitable for the present invention include a structure having a naphthyl group represented by the following formula (10) or a structure in which the naphthyl group of the formula (10) is substituted with a phenyl group. Among them, the compound of the formula (10) (hereinafter Eu (NTA)_ThreeIs abbreviated). Eu (NTA)_ThreeIs used as a fluorescent material for fluorescent immunoassay. Literature written by Yuan et al. P. Diamandis; Clin. Biochem. 21, 139 (1988).
[0038]
Embedded image

[0039]
Eu illustrated here³⁺And a fluorescent organic lanthanoid complex composed of a ligand having a β-diketonate group are particularly suitable as a material for a suspension ink described later.
<Organic lanthanoid complex having polymerizability>
As a material for the polymerizable ink of the present invention to be described later, an organic lanthanoid complex having polymerizability is suitable. The polymerizability here means polymerizability in an arbitrary polymerization format, and examples of the polymerization format include radical polymerization, anionic polymerization, cationic polymerization, coordination polymerization, ring-opening polymerization, condensation polymerization, etc. Radical polymerization is particularly preferable. Such polymerizability is usually imparted by introducing a functional group having polymerizability into the organic ligand (hereinafter referred to as “polymerizable group”). Suitable for this purpose is an organic lanthanoid complex containing a dendron bonded with a polymerizable group such as a radical polymerizable group as a ligand.
[0040]
Examples of the radical polymerizable group include a carbon-carbon multiple bond conjugated with an aromatic ring (for example, a styrene residue such as a 4-vinylphenyl group and a 3-vinylphenyl group, a 4-propargylphenyl group, a vinylnaphthalene residue, etc. Conjugated hydrocarbon structures, structures conjugated with nitrogen-containing aromatic rings such as vinylpyridine residues such as 4-vinylpyridyl group and 2-vinylpyridyl group), acrylic acid such as acryloyl group, methacryloyl group, or crotonoyl group, Conjugated hydrocarbon residue derived from unsaturated conjugated carboxylic acid derived from unsaturated conjugated carboxylic acid such as methacrylic acid or crotonic acid, conjugated hydrocarbon residue derived from unsaturated conjugated dicarboxylic acid such as maleic acid or fumaric acid such as malenoyl group or fumaroyl group Group having an allyl group (for example, 4-allylphenyl group, 4-allyloxyphenyl group, 4-a Le oxycarbonyl phenyl group), the structure (e.g., 4-vinyl oxy phenyl group having a vinyl ether structure or a vinyl ester structure, 4-vinyl oxycarbonyl phenyl group).
[0041]
From the viewpoint of polymerization reactivity in the polymerizable ink described later, it is desirable that the polymerizable group is bonded to the end of the non-focal point of the dendron. The number of polymerizable groups in one dendron is not limited, but in order to prevent excessive gelation during the polymerization reaction, the number of polymerizable groups is usually 1 to 8, preferably 1 to 6, More preferably, it is a natural number of 1 to 4, most preferably 1 to 3.
[0042]
Specific examples of the structure of the organic lanthanoid complex having a radical polymerizable dendron preferably used in the present invention as a ligand include all the substituents R in the general formulas (3) to (8) as vinyl groups. And lanthanoid complexes having a polybenzyl ether dendron having a 4-vinylphenyl group terminal as a ligand, and among these, the second generation polybenzyl ether dendron carboxy represented by the general formula (4) or (7). A complex having a rate as a ligand is very preferable in terms of a balance between ease of synthesis and luminance, and the first-generation polybenzyl ether dendron carboxylate represented by the general formula (3) or (6) is used as a ligand. The complex to be used is practically very useful in terms of luminance per unit weight of the complex. In the structures exemplified in the general formulas (3) to (8), an isomer in which the contained 4-vinylphenyl group end is replaced with any non-focal point end in the dendron structure has the same radical polymerizability. Needless to say, even if a dendron structure contains at most about three 4-vinylphenyl group ends as described above, preferable polymerizability is exhibited.
[0043]
<Solution-type ink>
A solution obtained by dissolving the organic lanthanoid complex in an arbitrary solvent can be used as the printing ink of the present invention. A printing ink produced from such a solution is referred to herein as a “solution-type ink”.
The concentration of the organic lanthanoid complex in the solution type ink is usually 0.01 to 90% by weight, preferably 0.1 to 75% by weight in terms of printability such as fluorescence ability, solubility, and solution viscosity. The amount is preferably about 1 to 60% by weight, and most preferably about 5 to 40% by weight, and the method for producing the solution type ink is not limited as long as it is dissolved at such a concentration.
[0044]
Solvents used in such solution-type inks include aromatic hydrocarbons such as toluene, xylene, styrene, α-methylstyrene, chlorobenzene, tetrahydrofuran (commonly called THF), methyl cellosolve, ethyl cellosolve, diethyl ether, benzyl methyl ether. Ethers such as methyl acetate, ethyl acetate, butyl acetate, benzyl acetate, ethyl propionate, ethyl acrylate, methyl methacrylate, n-butyl methacrylate, methylene chloride, chloroform, 1,1, Alkyl halides such as 1-trichloroethane and sym-tetrachloroethylene, ketones such as acetone and methyl ethyl ketone, N, N-dimethylacetamide, N, N-dimethylformamide (commonly called DMF), N-vinylformamide, N Aprotic amide solvents such as methylpyrrolidone (common name NMP) and N-vinylpyrrolidone, sulfoxides such as dimethyl sulfoxide (common name DMSO) and dibutyl sulfoxide, methanol, ethanol, n-propanol, isopropyl alcohol, n-butanol, isobutyl Lower alcohols such as alcohol, tert-butyl alcohol, lower glycols such as ethylene glycol, propylene glycol, butylene glycol, glycerin, erythritol, pentaerythritol, 2-ethyl-2-hydroxymethyl-1,3-propanediol, etc. Examples include polyhydric alcohols and water. These solvents may be used in combination of a plurality of types as necessary.
[0045]
Among the solvents exemplified here, radically polymerizable carbon-carbon such as styrene, α-methylstyrene, ethyl acrylate, methyl methacrylate, n-butyl methacrylate, N-vinylformamide, or N-vinylpyrrolidone. A solvent having multiple bonds may be particularly effective as a solvent for a polymerizable ink described later.
[0046]
Among these, solvents suitable for the case where the organic lanthanoid complex containing the aromatic dendron ligand is used as a raw material include aromatic hydrocarbons such as toluene, xylene, styrene, chlorobenzene, THF, benzyl methyl ether, and the like. Ethers, ethyl acetate, butyl acetate, benzyl acetate, carboxylic acid esters such as methyl methacrylate and n-butyl methacrylate, alkyl halides such as methylene chloride, ketones such as acetone and methyl ethyl ketone, N, N- Aprotic amide solvents such as dimethylacetamide, DMF and NMP, sulfoxides such as DMSO, etc. Among them, aromatic hydrocarbons such as toluene and chlorobenzene, ethers such as THF, and carboxylic acid esters such as ethyl acetate , Alkyl halides such as methylene chloride, aceto Ketones etc., aprotic amide solvents such as DMF or NMP are particularly preferred in terms of solubility.
[0047]
<Polymerizable ink>
The case where the printing ink of the present invention contains a polymerizable component is referred to herein as “polymerizable ink”. Specific examples of the polymerizable component include organic lanthanoid complexes having the above-described polymerizable properties, and solvents having the above-described radical polymerizable carbon-carbon multiple bonds. Such a polymerizable ink may be either of the above-described solution type ink in which an organic lanthanoid complex is dissolved or a suspension type ink in which fine particles of an organic lanthanoid complex described below are suspended and stabilized in a solvent. Is possible. In the case of the latter suspension type ink, if polymerized organic lanthanoid complex fine particles are used, the polymerizable group may be present on the surface of the fine particles, and such fine particles are classified as one of the polymerizable components. Conceivable.
[0048]
The polymerizable ink in the present invention can generate a polymer, more preferably a cross-linked polymer, by advancing a polymerization reaction in the ink after printing by any of the above-described polymerization methods (particularly preferred is radical polymerization). Intended. The formation of such a polymer has a favorable effect of greatly reducing the solvent solubility of the printed ink component and significantly improving the durability against external factors that deteriorate printing such as friction, heating, oxidation, and light degradation. There is a case. Particularly preferred is the use of the above-mentioned organic lanthanoid complex having polymerizability. This is due to the effect that the fluorescent substance itself, which is the source of the fluorescence ability of the printing ink of the present invention, is copolymerized and fixed to a polymer.
[0049]
The ratio of the polymerizable component in the polymerizable ink is usually 1 to 100% by weight with respect to the total ink weight, preferably 10 to 100% by weight, and more preferably 20 to 20% in terms of the effect due to the formation of the polymer. 100% by weight, most preferably 30-100% by weight.
For the purpose of producing a crosslinked polymer by a polymerization reaction, it is often preferable to add an appropriate crosslinking agent. Taking such a crosslinking agent as an example of radical polymerization, a compound containing a plurality of radical polymerizable groups in one molecule, that is, polyfunctional benzene such as divinylbenzene, N, N′-methylenebis (meth) acrylamide, N, N′-ethylenebis (meth) acrylamide, N, N′-butylenebis (meth) acrylamide, ethylene glycol di (meth) acrylate, butylene glycol di (meth) acrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, etc. Examples thereof include compounds having two or more (meth) acryloyl groups, divinyl adipate, bifunctional vinyl esters such as vinyl (meth) acrylate and vinyl crotonate. Of these, important ones commonly used are divinylbenzene, N, N'-methylenebisacrylamide, ethylene glycol diacrylate, divinyl adipate, vinyl acrylate, and the like. The amount of such a crosslinking agent used is usually 0.001 to 5%, preferably 0.01 to 4%, more preferably 0.05 to 3.5%, most preferably as a mole fraction in the total polymerizable molecule. Is about 0.1 to 3%.
[0050]
As a polymerizable component to be added to the polymerizable ink, any known radical-reactive monomer can be used in addition to the solvent having a radical polymerizable carbon-carbon multiple bond. Specifically, styrenes such as 4-acetoxystyrene and 4-chloromethylstyrene, (meth) acrylic acid esters such as N, N-dimethylaminoethyl (meth) acrylate, methyl crotonate, and n-butyl crotonate , Crotonates such as benzyl crotonate and N, N-dimethylaminopropyl crotonate, unsaturated conjugated carboxylic acids such as (meth) acrylic acid and crotonic acid, (meth) acrylamide, N-methyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, N, N-dimethylaminopropyl (meth) acrylamide, N- (meth) acryloylmorpholine, N-isopropyl (meth) acrylamide and the like ( (Meth) acrylamides, crotonilamide, N- Crotonylamides such as tilcrotonilamide, N, N-dimethylcrotonylamide, N-crotonylmorpholine, N-isopropylcrotonylamide, vinyl acetate, vinyl monochloroacetate, vinyl pivalate, vinyl butyrate, 2-ethyl Vinyl esters of carboxylic acids such as vinyl hexanoate, nitriles such as (meth) acrylonitrile, maleic anhydride, maleic acid, fumaric acid, diethyl maleate, dimethyl fumarate, monoethyl ester of maleic acid, maleimide, N- Examples thereof include conjugated unsaturated dicarboxylic acid derivatives such as methylmaleimide and N-phenylmaleimide, and N-vinyloxazoline.
[0051]
There are no limitations on the conditions for proceeding the polymerization reaction in the polymerizable ink, but in the case of radical polymerization, the polymerization is usually started by radical generation by application of heat or light. The amount of the radical generator used is usually 0.001 to 10% by weight, preferably 0.01 to 5% by weight, more preferably 0.05 to the weight of all radical polymerizable components in the polymerizable ink. -3% by weight, most preferably about 0.1-2% by weight. Typical examples of thermal radical generators used in polymerizable inks intended for radical polymerization include azo compounds such as N, N′-azobisisobutyronitrile (commonly known as AIBN), benzoyl peroxide, and the like. Peroxides are most commonly used, but are commercially available from water-soluble radical generators such as persulfates such as potassium persulfate and ammonium persulfate, or water-soluble azo compounds (eg Wako Pure Chemical Industries, Ltd.). Etc.) may be used. Examples of the general photo radical generator include aminoacetophenones such as α-aminoacetophenone and 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butane-1, and benzyl. Examples include dimethyl ketals, glyoxyesters, acylphosphineoxys, and the like.
[0052]
Any of the above-mentioned monomers having radical polymerizability, a crosslinking agent, and a radical generator may be used in combination of a plurality of types as required.
<Suspension ink>
A suspension obtained by suspending and stabilizing the fine particles of the organic lanthanoid complex in an arbitrary solvent can be used as the printing ink of the present invention. A printing ink produced from such a suspension is referred to herein as a “suspension ink”.
[0053]
There is no restriction | limiting in the solvent used for this suspension type ink, The specific example is the same as the illustration in the said solution type ink. However, the use of aqueous solvents such as water and alcohols is particularly suitable from the viewpoint of environmental safety and worker safety. The aqueous solvent here means water or a homogeneous mixed solvent containing water, and water is most preferable.
[0054]
There is no limitation on the substance that is mixed with water to give an aqueous solvent, as long as it is inactive so long as it has solubility in water and does not cause an undesirable chemical reaction to the organic lanthanoid complex. Lower alcohols such as ethanol, n-propanol, isopropyl alcohol, n-butanol, isobutyl alcohol, tert-butyl alcohol, lower glycols such as ethylene glycol, propylene glycol, butylene glycol, glycerin, erythritol, pentaerythritol, 2-ethyl Polyhydric alcohols such as 2-hydroxymethyl-1,3-propanediol, lower ketones such as acetone and methyl ethyl ketone, fats such as diethyl ether, tetrahydrofuran (commonly called THF), methyl cellosolve, and ethyl cellosolve Aprotic amides such as aliphatic ethers, esters of lower fatty acids such as methyl acetate and ethyl acetate, N, N-dimethylacetamide, N, N-dimethylformamide (common name DMF), N-methylpyrrolidone (common name NMP), etc. Examples of the solvent include sulfoxides such as dimethyl sulfoxide (commonly called DMSO) and dibutyl sulfoxide. These organic substances may be used in combination, and there is no limitation on the mixing ratio with water, but the water content in the aqueous solvent is usually 5 to 100% by weight, preferably 10 to 100% by weight. %, More preferably 20 to 100% by weight, and most preferably 30 to 100% by weight.
[0055]
In such a suspension type ink, the organic lanthanoid complex is suspended and stabilized as fine particles, and its number average particle size is usually 8 to 1000 nm, preferably 15 to 700 nm, more preferably 30 to 400 nm, most preferably Preferably, it is 50 to 200 nm. Such a particle size is measured by, for example, a general-purpose particle size measuring device such as a Coulter counter, a light scattering method, a microscope (an optical microscope or an electron microscope), and the like.
[0056]
The content of the organic lanthanoid complex in the suspension ink largely depends on the molecular weight of the complex, but the concentration of the lanthanoid element is usually 0.001 to 100 mmol / L, and the luminescence of the suspension From the balance of performance and suspension stability, it is preferably 0.005 to 50 mmol / L, more preferably 0.01 to 20 mmol / L, and most preferably about 0.05 to 5 mmol / L. Further, the weight ratio of the organic lanthanoid complex is usually 0.001 to 50% by weight, preferably 0.01 to 30% by weight, more preferably from the balance between the light emitting ability and suspension stability of the suspension type ink. 0.1 to 20% by weight, most preferably 1 to 10% by weight. The content of the organic lanthanoid complex is determined by gravimetric analysis of the distillation residue of the solvent from the suspension type ink, elemental analysis of the residue, ash content analysis when the suspension type ink is heated and burned, It can be measured by various qualitative / quantitative analyzes such as NMR spectrum and infrared absorption spectrum of the ink, or a combination thereof.
[0057]
<Method for producing aqueous suspension type ink>
As a method for producing a suspension-type ink using a particularly preferable aqueous solvent, a method in which an organic lanthanoid complex dispersed in an aqueous solvent is suspended and stabilized by mechanical crushing in the presence of a surfactant (hereinafter referred to as a crushing method). Can be exemplified. Such a method will be described below.
[0058]
In the above crushing method, it is preferable to first perform an operation (hereinafter referred to as pre-pulverization) in which the organic lanthanoid complex is mechanically made as fine as possible. This facilitates the formation of fine particles by “mechanical crushing” described later. Such pre-grinding is performed by using an existing arbitrary grinding device (for example, a grinding device based on the principle of “mortar and pestle”, a moving body such as a rotary hook or a belt, and a compressed body that forms a gap between the moving body. Such as a device that uses shear force in the gap, a device that pulverizes by the kinetic energy of a moving object such as a ball mill, a device that pulverizes by the kinetic energy of a collision with a wall surface, etc. The number average particle size of the obtained powder is usually 0.8 to 1000 μm, preferably 0.8 to 500 μm, more preferably 0.8 to 100 μm, and most preferably about 0.8 to 50 μm.
[0059]
Next, an aqueous dispersion (hereinafter referred to as a dispersion) in which the organic lanthanoid complex powder obtained by such pre-grinding is dispersed in the aqueous solvent is obtained. In this case, when an appropriate surfactant is used in combination, a favorable result is often given in terms of suspension stabilization in the mechanical crushing described later. This is because the surface of the lipophilic organic lanthanoid complex powder or crushed fine particles is coated with the lipophilic group of the surfactant, and the hydrophilic group of the surfactant facing outward is the powder or crushed organic lanthanoid complex. This is presumably due to the effect of stabilizing the fine particles in an aqueous solvent in a micellar manner. Suitable surfactants used herein include, for example, cationic surfactants such as sulfonates such as sodium dodecylbenzenesulfonate and sodium dodecylsulfonate, and carboxylates such as sodium palmitate and sodium stearate. Anionic surfactants bound with quaternary onium salts such as tetraethylammonium, nonionic surfactants bound with water-soluble structures such as polyethylene glycol chains, polyethylene glycol, polyvinyl pyrrolidone, polyvinyl pyridine, polyvinyl alcohol, etc. Water-soluble polymers are exemplified, and among them, cationic surfactants such as sulfonates such as sodium dodecylbenzenesulfonate and sodium dodecylsulfonate, and carboxylates such as sodium palmitate and sodium stearate are suitable. That.
[0060]
In order to obtain the suspension-type ink of the present invention using an aqueous solvent, the dispersion is subjected to an arbitrary mechanical crushing treatment. “Mechanical crushing” in the present invention refers to crushing an organic lanthanoid complex powder existing in the dispersion by applying any mechanical impact force such as collision, shearing, compression or expansion to the powder. Means. Such mechanical impact force may be any mechanical interaction between the powders of the organic lanthanoid complex, between the powder and the structure of the inner wall of the apparatus, or between the powder and the aqueous solvent. Caused by action. As a specific method of such mechanical crushing, a method of high-pressure injection of the above dispersion into a capillary having an inner wall material made of any material excellent in hardness and strength (for example, metal, semiconductor, ceramics, glass, diamond, etc.), Examples include a method of causing the dispersion to collide at high speed with the surface of an arbitrary material having the same hardness and strength, a method of abruptly releasing the high-pressure dispersion, and the like. From the viewpoint of the crushing effect, a method of high-pressure injection into a thin tube is preferable. The injection pressure in the high-pressure injection into such a thin tube is usually 100 to 5000 kg / cm.²In view of the effect of mechanical crushing and the pressure resistance of the device, preferably 300 to 4000 kg / cm²More preferably, 500 to 3000 kg / cm², Most preferably 700-2000 kg / cm²A range of about. Further, the temperature of the dispersion liquid when the mechanical crushing occurs is preferably controlled to a temperature at which boiling of the aqueous solvent does not occur at the pressure at that time, usually 20 to 200 ° C., preferably 20 to 150 ° C. Preferably it is 20-130 degreeC, Most preferably, it is set as about 20-120 degreeC. Such a temperature can be estimated by measuring the actual temperature of the dispersion at the location of the apparatus where mechanical crushing occurs, or by measuring the temperature of a nearby material.
[0061]
In such an exemplary method, for the purpose of increasing the effect of mechanical crushing, an arbitrary three-dimensional structure (for example, a protrusion having an arbitrary shape such as a wedge shape or a rectangular parallelepiped) A surface shape change such as a depression, a slit, a baffle plate, a stirring blade, etc.) may be installed.
Desirably, the pulverized fine particles of the organic lanthanoid complex produced by the mechanical pulverization are suspended and stabilized in an aqueous solvent by an arbitrary effect such as the effect similar to the micelle formation of the surfactant. . At this time, for example, an amphipathic molecule such as the surfactant molecule or a polar molecule having a polar group such as a carbonyl group, a hydroxyl group, or an amino group is added to the dispersion in advance as a stabilizing molecule. It often gives good results. The mechanism of action is arbitrary as long as such a stabilizing molecule exhibits a preferable suspension stabilizing effect. For example, the mechanism is similar to micelle formation in the above-mentioned surfactant, or is stabilized by a mechanochemical reaction by mechanical crushing. It is assumed that the chemical bond between the molecule and the surface of the crushed fine particles of the organic lanthanoid complex is newly generated.
[0062]
<Printing method using polymerizable ink>
The printing method comprising the step of polymerizing the polymerizable component in the printing ink of the present invention is preferable from the viewpoint of durability of printing quality as described above for the polymerizable ink. In particular, when radical polymerization is allowed to proceed, a printing method that undergoes an arbitrary radical polymerization step such as thermal radical polymerization or photoradical polymerization is suitable. In any radical polymerization, the heat treatment described later is effective.
[0063]
In the case of thermal radical polymerization, the printed surface after printing is heated above the decomposition temperature of the thermal radical generator. The heating temperature is usually 40 to 180 ° C., preferably 50 to 160 ° C., more preferably 55 to 140 ° C., and most preferably 60 from the viewpoints of polymerization and thermal deterioration of the organic lanthanoid complex and volatilization prevention of the radical polymerizable component. ˜130 ° C. The heating time is usually 1 to 36000 seconds depending on the heating temperature, preferably 5 to 18000 seconds, more preferably 10 to 9000 seconds, and most preferably about 15 to 3600 seconds in terms of polymerizability and productivity. And It is also possible to design a preferable thermal radical polymerization by changing the heating temperature during the heating time. For example, in the initial stage of heating, heating is carried out at a relatively low temperature of about 40 to 90 ° C. to generate radicals while preventing volatilization of the polymerizable component, and then polymerization is started, followed by rapid radical polymerization at a high temperature of about 90 to 180 ° C. It is conceivable to design the reaction such that the reaction proceeds.
[0064]
In the case of photoradical polymerization, the printed surface after printing is first irradiated with light having a wavelength that can decompose the photoradical generator, and then usually heated for the purpose of promoting polymerization. The heating temperature range and time are the same as those described in the case of the thermal radical polymerization. It is also possible to design a preferred radical polymerization by changing the heating temperature during the heating time. For example, in the initial stage of heating, radical polymerization is gradually progressed while heating at a relatively low temperature of about 40 to 90 ° C. to prevent volatilization of polymerizable components, and then radical polymerization is rapidly advanced at a high temperature of about 90 to 180 ° C. It is conceivable to design the reaction.
[0065]
In any of the heat treatments, in order to suppress undesirable side reactions such as air oxidation and hydrolysis, an atmosphere of an inert gas such as dry nitrogen or dry air may be preferable. Further, for the purpose of improving printing productivity, it is possible to apply the heat treatment and light irradiation a plurality of times in a continuous printing line. Alternatively, it is possible to add or add a thermal annealing process for heating and storing the printed matter at an arbitrary temperature after the printing process so that radical polymerization proceeds or is completed.
[0066]
<Uses such as counterfeit detection printing>
The printing ink of the present invention may use an aqueous solvent (for example, water or water-containing ethanol) having excellent brightness and color purity of an organic lanthanoid complex used as a phosphor and excellent environmental safety as a medium. It is possible and is excellent in long-term storage stability in which precipitation does not easily occur. Further, it is excited by ultraviolet rays generated by a general-purpose mercury lamp, and the excitation wavelength and the emission wavelength are largely separated.
[0067]
Due to recent advances in printing and copying technology, there are concerns about the increase in counterfeiting of printed materials such as banknotes, credit cards, bank cards such as banks and cash cards, identification cards, passports, etc. . In addition, it is well known that the above-mentioned various money cards have been discussed from the sudden increase in the number of personal internet transactions such as electronic money, and the necessity of countermeasures against card forgery.
[0068]
When the printing ink of the present invention is used for such a printed matter, the authenticity of the printed matter can be inspected extremely simply. For example, it can be easily visually detected by high-intensity visible fluorescence generated by the printing ink of the present invention by irradiation with a portable mercury lamp. This is because of the two properties of the organic lanthanoid complex that emits light with high brightness by the sensitization effect: (1) the property excited by ultraviolet rays, and (2) the excitation wavelength and the emission wavelength are largely separated. In daily lighting conditions with low UV content, such as sunlight and general-purpose lighting fixtures, light emission does not occur substantially at an intensity that can be visually confirmed, but light is emitted at an intensity that can be visually confirmed for the first time under irradiation conditions of ultraviolet rays of a specific wavelength. It depends on the principle. Therefore, it is desirable that the printing ink of the present invention has a large difference between the excitation wavelength and the emission wavelength derived from the fluorescence ability of the organic lanthanoid complex contained therein.
[0069]
Tb³⁺And Eu³⁺The organic complexes of trivalent lanthanoid cations such as those described above are generally characterized by fluorescence due to the transition of specific f-orbital electrons. Has a characteristic that the peak wavelength hardly fluctuates. On the other hand, with respect to the excitation wavelength, light can be emitted at an arbitrary wavelength within the range of the excitation spectrum given by the organic lanthanoid complex, and therefore an arbitrary wavelength within this range can be determined as the excitation wavelength as necessary. Therefore, the difference between the excitation wavelength and the emission wavelength of the printing ink of the present invention described above is the difference between the excitation wavelength and the peak wavelength λem of the main emission band (that is, the emission band giving the maximum luminance) of the organic lanthanoid complex contained in the ink. The difference (λem−λex) from an arbitrary excitation wavelength λex within the range is usually 50 nm or more, preferably 100 nm or more, more preferably 150 nm or more, and most preferably 200 nm or more.
[0070]
For example, Tb that emits green light³⁺Eu emitting red light³⁺Taking an organic complex of a different lanthanoid cation as an example, each of them has a plurality of emission bands having a specific emission wavelength and a narrow half-value width. By measuring the emission spectrum, it can be easily identified as if the individual was identified by a fingerprint. Furthermore, the combined use of a plurality of types of printing inks of the present invention containing these different kinds of organic lanthanoid complexes makes it possible to form a more complicated printed pattern, which helps to prevent counterfeiting.
[0071]
When it is intended to form a complex print pattern that is difficult to counterfeit based on this concept, a plurality of types of organic lanthanoid complexes may be mixed at an arbitrary blending ratio and used in the printing ink of the present invention. In order to perform precise printing, means suitable for fine printing, such as an ink jet method, is preferable.
<Resin molding>
The resin molded body having a printing surface using the printing ink of the present invention is useful due to the above characteristics, and is suitably used, for example, as various cards (credit card, cash card, ID card, etc.) that are difficult to forge. The However, the shape of such cards is only an example, and the shape of the resin molded body of the present invention is not limited. Possible practical shapes include bottles such as PET bottles, sheet shapes such as OHP sheets, box-shaped shapes such as compact cassette tapes and video cassette tapes, disk shapes such as compact discs, optical Examples include fiber shapes such as fibers and fishing lines, spherical shapes such as resin beads, and film shapes such as agricultural films and food packaging films.
[0072]
The shape and thickness of the printing layer derived from the printing ink of the present invention fixed on the printing surface is not limited, but the thickness of the printing layer is usually from the standpoint of its mechanical strength and printing effect. The thickness is about 1 to 5000 μm, preferably about 1 to 1000 μm, more preferably about 0.8 to 500 μm, and most preferably about 0.5 to 200 μm. In the resin molded body of the present invention, the organic lanthanoid complex, which is an essential component of the printing ink of the present invention, is a necessary condition because it exhibits fluorescence on the printed surface of the resin molded body. The complex does not necessarily have to be entirely present on the printed surface, and part or all of the complex may be present by penetrating into the resin surface layer of the printed surface. The penetration depth of the organic lanthanoid complex into the resin surface layer on the printed surface is not limited, but is usually 10 mm or less, preferably 7 mm or less, more preferably 4 mm or less, most preferably in terms of fluorescence ability when irradiated with excitation light. Control to 1 mm or less.
[0073]
The resin used in the resin molded body of the present invention is not limited. For example, polyolefins such as polyethylene resin and polypropylene resin, PVC resins such as polyvinyl chloride, PVDC resins such as polyvinylidene chloride, and polystyrene resin Styrene-acrylonitrile copolymer (commonly known as SAN), acrylonitrile-butadiene-styrene copolymer (commonly known as ABS), acrylonitrile-styrene copolymer grafted on acrylic rubber, commonly known as AAS resin, EPDM (ethylene-diene monomer copolymer) ) Acrylonitrile-styrene copolymer grafted on rubber, commonly known as EAS resin, high impact polystyrene resin (commonly known as HIPS), syndiotactic polystyrene resin and other styrenic resins, polymethyl methacrylate resin (commonly known as PMMA) Resin, ethylene-vinyl alcohol copolymer (commonly known as EVAL), etc., thermoplastic resins such as thermoplastic polyurethane resin, polyethylene terephthalate resin (commonly known as PET), polybutylene terephthalate resin (commonly known as PBT), polyethylene Aromatic polyester resins such as phthalate resin (common name PEN), polyoxymethylene resin (common name POM), nylon 6, nylon 66, nylon 46, nylon 11, nylon 12, nylon 610, nylon 612, terephthalic acid and / or isophthalic acid Polyamide obtained from styrene and hexamethylene diamine, Polyamide obtained from terephthalic acid and / or isophthalic acid, adipic acid and hexamethylene diamine, including 1,3-phenylenedioxydiacetic acid as a copolymerization component Polymerized polyamide, polyamide resin such as copolymerized polyamide containing dimerized fatty acid as a copolymerization component, aromatic polycarbonate resin such as bisphenol A polycarbonate (commonly called PC), polyphenylene ether resin such as poly (2,6-dimethylphenol) (Commonly known as PPE), polyphenylene sulfide resin (commonly known as PPS), thermoplastic engineering plastics (so-called engineering plastics) such as polyarylene sulfide resin such as fluorine resin, polysulfone resin (commonly known as PSU), polyethersulfone resin (commonly known as PES), poly So-called super engineering plastics such as arylate resin (common name PAR), polyimide resin (common name PI), polyetheretherketone resin (common name PEEK), liquid crystal polymer (common name LCP), unsaturated polyester resin, epoxy Examples thereof include curable resins such as resins, phenol resins, urea (urea) resins, melamine resins, diallyl phthalate resins, and silicone resins. Of these, polypropylene resin, polyvinyl chloride fats, SAN resin, ABS resin, PMMA resin, PC resin, PET resin in terms of the balance of economic properties, mechanical properties such as rigidity and toughness, moldability, productivity, etc. A thermoplastic resin such as is preferable.
[0074]
These resins may be used as a so-called polymer alloy material in which a plurality are blended. Also optional additives such as antioxidants, heat stabilizers, stabilizers such as light stabilizers, glass fiber, glass beads, mica, talc, kaolin, clay mineral, carbon fiber, carbon black, graphite, metal fiber , Fillers such as metal powders, antistatic agents, mold release agents, plasticizers, additives such as UV absorbers, colorants such as pigments and dyes, impact imparting agents such as rubber and elastomer It is also possible to mix any additive accordingly.
[0075]
In obtaining the resin molded body of the present invention, a chemical reaction such as an oxidation reaction such as an optional surface treatment (for example, plasma treatment, corona treatment, ozone treatment, open flame treatment, acid or alkali treatment) is performed on the printing surface before printing in advance. It is also possible to perform a treatment to be applied, a treatment to apply various primers to form an adhesive layer, a water absorption treatment, a friction treatment to give fine scratches, etc.).
[0076]
【Example】
Specific examples of the present invention will be described below in more detail with reference to examples. However, the present invention is not limited to these examples unless it exceeds the gist. [Measurement equipment and conditions]
(1) NMR: JNM-EX270 type FT-NMR (manufactured by JEOL Ltd.)¹H: 300 MHz) Solvent: CDCl_Three.
(2) FT-IR: FT / IR-8000 type FT-IR manufactured by JASCO Corporation is used, and amorphous material is KBr method or liquid film method (cast film of sample methylene chloride solution on salt crystal) In preparation, the crystalline substances were measured by the KBr disk method.
(3) Fluorescence spectrum: Measured in the atmosphere at room temperature using an F-3000 fluorometer manufactured by Hitachi, Ltd.
[0077]
[Synthesis Examples and Examples]
Synthesis Example 1: Organic Tb with first generation dendron as ligand³⁺Complex synthesis
The above-mentioned M.M. In the literature by Kawa et al., The same synthesis was performed using 3,4-dihydroxybenzoic acid (hereinafter abbreviated as 34DHBEt) instead of 3,5-dihydroxybenzoic acid which is a raw material of the focal point portion. A next generation polybenzyl ether structure carboxylate dendron was synthesized (abbreviated as [34G1] COOH). That is, 34DHBEt (1 equivalent), benzyl bromide (2.05 equivalent), 18-crown-6-ether (0.2 equivalent), and anhydrous potassium carbonate (just ground in a mortar, 2.5 equivalents) in acetone. A dendron skeleton was constructed by an etherification reaction heated at reflux, and then hydrolyzed in a THF / methanol-containing aqueous solution containing 3 equivalents of potassium hydroxide with respect to the ethyl ester group. The procedure for purification with crystals was followed. This product is 1680 cm in the FT-IR spectrum.^-1Giving absorption attributed to the carbonyl group of the nearby carboxylic acid and OH stretching vibration also attributed to the carboxyl group,¹The structure of the H-NMR spectrum is given by giving signals attributed to the terminal phenyl group (10 protons), the benzyl group (2 types, total 4 protons), and the benzene ring (3 protons) that is the branching point. confirmed. [34G1] COOH (3 equivalents) thus obtained was mixed with terbium acetate (III) anhydrous salt (1 equivalent), heated under reflux in chlorobenzene, and then acetic acid produced together with the solvent was distilled off under reduced pressure to give [34G1] COOH. Organic Tb with Carboxylate as Ligand³⁺Complex ([34G1]_Three(Abbreviated as Tb). This product is 1680 cm in the FT-IR spectrum.^-1Since the absorption attributed to the carbonyl group of the nearby carboxylic acid and the OH stretching vibration attributed to the carboxyl group are not given, the raw carboxylic acid [34G1] COOH is converted to the corresponding carboxylate. Tb³⁺It was thought that a complex was formed. [34G1]_ThreeA part of Tb was finely ground in a mortar and used in the following examples.
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Synthesis Example 2: Organic Tb with second-generation dendron as ligand³⁺Complex synthesis
The corresponding second generation carboxylate dendron was synthesized by the dendrimer synthesis strategy of Synthesis Example 1 (abbreviated as [34G2] COOH). That is, in Synthesis Example 1, the same synthesis operation was performed using 3,5-dibenzyloxybenzyl bromide supplied from Tokyo Chemical Industry Co., Ltd. instead of benzyl bromide. This product is 1680 cm in the FT-IR spectrum.^-1Giving absorption attributed to the carbonyl group of the nearby carboxylic acid and OH stretching vibration also attributed to the carboxyl group,¹In H-NMR spectrum, signals attributed to terminal phenyl group (20 protons), benzyl group (3 types; 4 protons, 2 protons, 2 protons) and three benzene rings as branching points (9 protons in total) The structure was confirmed. The same operation was performed using [34G2] COOH thus obtained instead of [34G1] COOH in Synthesis Example 1, and organic Tb having [34G2] COOH carboxylate as a ligand was used.³⁺Complex ([34G2]_Three(Abbreviated as Tb). This product is 1680 cm in the FT-IR spectrum.^-1Since the absorption attributed to the carbonyl group of the nearby carboxylic acid and the O—H stretching vibration attributed to the carboxyl group are not given, the raw carboxylic acid [34G2] COOH is converted into the corresponding carboxylate. Tb³⁺It was thought that a complex was formed.
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Synthesis Example 3: Organic Eu having a naphthalene derivative as a ligand³⁺Complex synthesis
J. Eu (NTA) by a method known in the literature of Yuan et al._Three(For the structure, see Formula 10 above) was synthesized. That is, 4,4,4-trifluoro-1- (2-naphthyl) -1,3-butanedione (4.27 g; 3 equivalents) was mixed with ethanol (38 mL), methanol (18 mL), and water (1 mL). It melt | dissolved in the solvent at room temperature, and stirred with the mechanical stirring blade of an electric motor power. To this yellow solution was added 28% aqueous ammonia (0.97 g; 3 equivalents), and an aqueous solution prepared by dissolving separately prepared europium chloride hexahydrate (1.96 g; 1 equivalent) in water (64 mL) was added for 1 hour. The resulting solution was dropped to obtain a highly viscous precipitate. The residue obtained by concentration was dissolved in acetone, and the acetone solution obtained by filtering insolubles was poured into a large amount of ice water with vigorous stirring. The resulting precipitate is filtered off and washed thoroughly with water to obtain the desired Eu (NTA)_ThreeGot.
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Synthesis Example 4: Organic Tb having a radical-polymerizable first generation dendron as a ligand³⁺Complex synthesis
4-vinylbenzyl chloride (Aldrich, 1.0 equivalent), ethyl 3,4-dihydroxybenzoate (1.0 equivalent), anhydrous potassium carbonate (2.5 equivalent), 18-crown-6 ether (0. 2 equivalents) and tetraethylammonium bromide (1.0 equivalents) were added to dry acetone, a catalytic amount of 2,6-di-tert-butyl-4-methylphenol was added, and the mixture was heated and stirred at 60 ° C. The reaction was monitored by commercially available silica gel thin layer chromatography (TLC). After confirming the disappearance of 4-vinylbenzyl chloride, benzyl bromide (1.0 equivalent) was added and the reaction was further continued. After confirming the disappearance of benzyl bromide by TLC, the mixture was concentrated. The residue was separated between two phases of methylene chloride and water, and the organic phase was concentrated to obtain a crude product. This was purified by silica gel column chromatography (n-hexane / ethyl acetate system), and a first-generation ester dendron (hereinafter referred to as ether-bonded 3,4-dioxybenzoic acid residue with one vinylbenzyl group and one benzyl group). V [34G1] COOEt). This structure is 1710 cm in the FT-IR spectrum.^-1An absorption band derived from the carbonyl group of the ester group is observed in the vicinity, and¹In H-NMR spectrum, methyl group (triplet / 3H) and methylene group (quartet / 2H), benzylic proton (4H), three kinds of vinyl group protons (doublet / 1H, double doublet / 1H, and double doublet in ethoxy group / 1H) and aromatic protons (1H, 9H, and 2H) were observed. Thereafter, it was converted into the corresponding carboxylic acid dendron by hydrolysis similar to Synthesis Example 1 and then neutralization with hydrochloric acid. The structure of the first-generation carboxylic acid dendron thus obtained (hereinafter abbreviated as V [34G1] COOH) showed that an absorption band of a carbonyl group attributed to a carboxyl group was observed in the FT-IR spectrum, and¹This was confirmed by the absence of a signal attributed to the ethoxy group in H-NMR. The V [34G1] COOH thus obtained was used in Synthesis Example 1 in place of [34G1] COOH, and the same operation was carried out, and an organic Tb having a V [34G1] COOH carboxylate as a ligand.³⁺Complex (V [34G1]_Three(Abbreviated as Tb). Since this product does not give absorption attributed to the carbonyl group of the carboxylic acid and OH stretching vibration attributed to the carboxyl group in the FT-IR spectrum, V [34G1], which is the raw material carboxylic acid COOH is converted to the corresponding carboxylate and Tb³⁺It was thought that a complex was formed.
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<Preparation of aqueous suspension>
Synthesis Example 5: Organic Tb with dendron as ligand³⁺Aqueous suspension of complex
Sodium dodecylbenzenesulfonate (hereinafter abbreviated as SDS, 0.2 g) was dissolved in water (99.5 g), and the organic Tb obtained in Synthesis Example 1 was dissolved therein.³⁺Complex [34G1]_ThreeTb ground powder (number average particle size is about 5 μm, 0.3 g) was added and gently stirred at room temperature. Add more SDS (0.3 g) while continuing to stir, then [34G1]_ThreeAdditional Tb ground powder (0.2 g) was added. This aqueous dispersion is sealed in a glass bottle and shaken vigorously, and immediately after that, Nanomizer YSNM1500-5 ultra-fine atomization tabletop experimental equipment manufactured by Yoshida Kikai Kogyo Co., Ltd. In addition to the raw material liquid inlet of Japanese Patent No. 2788010, for example, mechanical crushing was performed by high-pressure collision force. At this time, the pressure applied to the aqueous dispersion was 130 megapascals, and the apparatus was passed once. As a result, when the organic Tb was allowed to stand for at least 45 days after standing at room temperature,^{Three +}An aqueous suspension in which the complex was suspended and stabilized was obtained. When this aqueous suspension is irradiated with ultraviolet rays emitted from a general-purpose mercury lamp having a wavelength of 365 nm, the Tb³⁺The complex gave a bright green fluorescence characteristic of the complex. The fluorescence spectrum of this aqueous suspension was measured in a quartz cell having an optical path length of 1 cm with an excitation wavelength of 300 nm. As a result, Tb including the main emission band near 542 nm was obtained.³⁺It was confirmed to be good in color purity, unique to cations and having a main emission band half width of about 17 nm.
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Synthesis Example 6: Organic Eu having a naphthalene derivative as a ligand³⁺Aqueous suspension of complex
In Synthesis Example 5, organic Tb³⁺Complex [34G1]_ThreeOrganic Eu having the naphthalene derivative obtained in Synthesis Example 3 as a ligand instead of the ground powder of Tb³⁺Complex Eu (NTA)_ThreeWhen the same operation is performed except that the pulverized powder (number average particle diameter is about 5 μm) is used, the organic Eu is not precipitated to the extent that it remains at room temperature.³⁺An aqueous suspension in which the complex is suspended and stabilized is obtained. When this aqueous suspension is irradiated with ultraviolet rays emitted from a general-purpose mercury lamp having a wavelength of 365 nm, the Eu³⁺A bright red fluorescence peculiar to the complex is given, and the fluorescence spectrum of this aqueous suspension is measured in the same manner as in Synthesis Example 5 with an excitation wavelength of 300 nm. Eu is emitted from the main emission band around 612 nm.³⁺It is confirmed that it is unique to cations and has a narrow color purity with a half-value width of several tens of nm as the main emission band.
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Example 1: Organic Tb³⁺Aqueous suspension ink containing complex
The fluorescent aqueous suspension obtained in Synthesis Example 5 is concentrated to ¼ volume, and here, polyethylene oxide having an average molecular weight of 300,000 (hereinafter abbreviated as PEO, the amount of 2% by weight in the concentrated solution) Was dissolved to obtain an aqueous suspension type ink. When this was applied to paper and dried, a printed surface having good fixability and the same green fluorescent ability as described in Synthesis Example 5 was obtained.
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Example 2: Organic Eu³⁺Aqueous suspension ink containing complex
In Example 1, except that the fluorescent aqueous suspension obtained in Synthesis Example 6 was used, when the same operation was performed, the fixing property was good and the same red fluorescence ability as described in Synthesis Example 6 was obtained. A printing surface having is obtained.
Example 3: Organic Tb³⁺Solution-type ink containing complex
Organic Tb with the second-generation dendron obtained in Synthesis Example 2 as a ligand³⁺Complex [34G2]_ThreeTb (20 parts by weight) was dissolved in a THF / toluene mixed solvent (weight mixing ratio = 80/20; 80 parts by weight) to obtain a solution-type ink. This was spray-coated on a polymethylmethacrylate (PMMA) resin plate heated to 90 ° C. and dried with hot air to obtain a printed surface with good fixability. When this printed surface is irradiated with ultraviolet rays emitted from a general-purpose mercury lamp having a wavelength of 365 nm, the Tb³⁺The complex gave a bright green fluorescence characteristic of the complex. When the fluorescence spectrum of this printed surface is measured at an excitation wavelength of 300 nm, Tb including the main emission band near 542 nm is obtained.³⁺It was confirmed to be good in color purity that is unique to cations and has a main emission band half width of about 20 nm.
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Example 4: Organic Tb³⁺Polymeric solution type ink containing complex
Organic Tb used in Example 3³⁺Complex ([34G2]_ThreeTb, 5 parts by weight), benzyl acrylate (45 parts by weight), and AIBN (1 part by weight) are dissolved in the THF / toluene mixed solvent (49 parts by weight) used in Example 3 to obtain a solution-type ink. When this is spray-coated on a polyethylene terephthalate (PET) resin molded body heated to 90 ° C. and heat-fixed in a 90 ° C. nitrogen stream oven, a printed surface with good fixability is obtained. This printed surface has the same green fluorescence as described in Example 3.
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Example 5: Polymerizable organic Tb³⁺Polymeric solution type ink containing complex
Polymerizable organic Tb obtained in Synthesis Example 4³⁺Complex V [34G1]_ThreeTb (10 parts by weight), benzyl acrylate (40 parts by weight), and AIBN (1 part by weight) are dissolved in the THF / toluene mixed solvent (49 parts by weight) used in Example 3 to obtain a solution-type ink. When this is spray-coated on a PET resin molded article in the same manner as in Example 4 and then heat-fixed, a good printed surface is obtained. When this printed surface is irradiated with ultraviolet rays emitted from a general-purpose mercury lamp having a wavelength of 365 nm, the Tb³⁺When a bright green fluorescence peculiar to the complex is given and the fluorescence spectrum of this printed surface is measured with an excitation wavelength of 300 nm, Tb including a main emission band near 542 nm is obtained.³⁺It is confirmed that it is unique to cations and has good color purity with a half-value width of the main emission band of about 20 nm.
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【The invention's effect】
Since the printing ink of the present invention contains an organic lanthanoid complex, it has excellent luminance and color purity. In addition, since the complex is in a dissolved state or in a suspended state as fine particles, it has excellent long-term storage stability that does not substantially form a precipitate, and is excellent in environmental safety if an aqueous solvent is used. Become. In addition, since it emits light by excitation at 365 nm wavelength by a general-purpose mercury lamp, and the excitation wavelength and the emission wavelength are largely separated from each other, for example, the authenticity of printed matter such as money cards and banknotes that needs to be prevented from being duplicated. It is useful for various printing applications using fluorescence, such as counterfeit detection printing for easily visually detecting the light by irradiation with a portable mercury lamp.
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing dendrimer generations and focal points.

Claims (10)

A printing ink containing an organic lanthanoid complex, wherein the organic lanthanoid complex contains an aromatic dendron having an aromatic polyether in a repeating unit as a ligand . The printing ink according to claim 1, wherein the aromatic dendron has a carboxylate group at a focal point . The printing ink according to claim 1 or 2 , wherein the organic lanthanoid complex contains a terbium or europium cation. The printing ink according to any one of claims 1 to 3, which is a solution of an organic lanthanoid complex. The printing ink according to any one of claims 1 to 3, wherein the organic lanthanoid complex is a suspension in which the suspension is stabilized. The printing ink according to claim 5, wherein the suspension is an aqueous suspension.   The printing ink according to claim 1, which contains a polymerizable component.   The method for producing a printing ink according to claim 6, wherein the organic lanthanoid complex dispersed in the aqueous solvent is suspended and stabilized by mechanical pulverization in the presence of a surfactant.   The printing method using the printing ink according to claim 7, further comprising a step of polymerizing a polymerizable component in the printing ink. A resin molded body having a printing surface using the printing ink according to claim 1.

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