JP2004322349A - Ink liquid feeding member for inkjet, and inkjet recording method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a recording instrument which can improve corrosion resistances to a photo-curing ink, prevent ink clogging and ink leakage even when used for a long time, stably secure an ink droplet discharging precision, and also reduce effects on ink sensitivity. <P>SOLUTION: In an ink liquid feeding member for inkjet using the photo-curing ink, a liquid feeding pump for feeding the ink from an ink storing part to an inkjet head is a tube pump. A ratio A/B of a contact area A (cm<SP>2</SP>) between a tube and a tube pump pressuring member for crushing the tube when feeding the photo-curing ink, and a tube pipe internal area B (cm<SP>2</SP>) is not smaller than 10 but not larger than 150. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【００６８】
一般式（１）において、Ｒ^１は水素原子やメチル基、エチル基、プロピル基、ブチル基等の炭素数１〜６のアルキル基、炭素数１〜６のフルオロアルキル基、アリル基、アリール基、フリル基またはチエニル基である。Ｒ^２は、メチル基、エチル基、プロピル基、ブチル基等の炭素数１〜６個のアルキル基、１−プロペニル基、２−プロペニル基、２−メチル−１−プロペニル基、２−メチル−２−プロペニル基、１−ブテニル基、２−ブテニル基、３−ブテニル基等の炭素数２〜６個のアルケニル基、フェニル基、ベンジル基、フルオロベンジル基、メトキシベンジル基、フェノキシエチル基等の芳香環を有する基、エチルカルボニル基、プロピルカルボニル基、ブチルカルボニル基等の炭素数２〜６個のアルキルカルボニル基、エトキシカルボニル基、プロポキシカルボニル基、ブトキシカルボニル基等の炭素数２〜６個のアルコキシカルボニル基、またはエチルカルバモイル基、プロピルカルバモイル基、ブチルカルバモイル基、ペンチルカルバモイル基等の炭素数２〜６個のＮ−アルキルカルバモイル基等である。本発明で使用するオキセタン化合物としては、１個のオキセタン環を有する化合物を使用することが、得られるインクが粘着性に優れ、低粘度で作業性に優れるため、特に好ましく用いられる。
【００６９】
２個のオキセタン環を有する化合物の一例としては、下記一般式（２）で示される化合物等が挙げられる。
【００７０】
【化２】

【００７１】
一般式（２）において、Ｒ^１は、上記一般式（１）におけるそれと同様の基である。Ｒ^３は、例えば、エチレン基、プロピレン基、ブチレン基等の線状または分枝状アルキレン基、ポリ（エチレンオキシ）基、ポリ（プロピレンオキシ）基等の線状または分枝状ポリ（アルキレンオキシ）基、プロペニレン基、メチルプロペニレン基、ブテニレン基等の線状または分枝状不飽和炭化水素基、またはカルボニル基またはカルボニル基を含むアルキレン基、カルボキシル基を含むアルキレン基、カルバモイル基を含むアルキレン基等である。
【００７２】
また、Ｒ^３としては、下記一般式（３）、（４）及び（５）で示される基から選択される多価基も挙げることができる。
【００７３】
【化３】

【００７４】
一般式（３）において、Ｒ^４は、水素原子やメチル基、エチル基、プロピル基、ブチル基等の炭素数１〜４個のアルキル基、メトキシ基、エトキシ基、プロポキシ基、ブトキシ基等の炭素数１〜４個のアルコキシ基、塩素原子、臭素原子等のハロゲン原子、ニトロ基、シアノ基、メルカプト基、低級アルコキシカルボニル基、カルボキシル基、またはカルバモイル基である。
【００７５】
【化４】

【００７６】
一般式（４）において、Ｒ^５は、酸素原子、硫黄原子、メチレン基、ＮＨ、ＳＯ、ＳＯ_２、Ｃ（ＣＦ_３）_２、またはＣ（ＣＨ_３）_２を表す。
【００７７】
【化５】

【００７８】
一般式（５）において、Ｒ^６は、メチル基、エチル基、プロピル基、ブチル基等の炭素数１〜４個のアルキル基、またはアリール基である。ｎは０〜２０００の整数である。Ｒ^７はメチル基、エチル基、プロピル基、ブチル基の炭素数１〜４個のアルキル基、またはアリール基である。Ｒ^７としては、更に、下記一般式（６）で示される基から選択される基も挙げることができる。
【００７９】
【化６】

【００８０】
一般式（６）において、Ｒ^８は、メチル基、エチル基、プロピル基、ブチル基等の炭素数１〜４個のアルキル基、またはアリール基である。ｍは０〜１００の整数である。
【００８１】
２個のオキセタン環を有する化合物の具体例としては、下記化合物が挙げられる。
【００８２】
【化７】

【００８３】
例示化合物１は、前記一般式（２）において、Ｒ^１がエチル基、Ｒ^３がカルボキシル基である化合物である。また、例示化合物２は、前記一般式（２）において、Ｒ^１がエチル基、Ｒ^３が前記一般式（５）でＲ^６及びＲ^７がメチル基、ｎが１である化合物である。
【００８４】
２個のオキセタン環を有する化合物において、上記の化合物以外の好ましい例としては、下記一般式（７）で示される化合物がある。一般式（７）において、Ｒ^１は、前記一般式（１）のＲ^１と同義である。
【００８５】
【化８】

【００８６】
また、３〜４個のオキセタン環を有する化合物の一例としては、下記一般式（８）で示される化合物が挙げられる。
【００８７】
【化９】

【００８８】
一般式（８）において、Ｒ^１は、前記一般式（１）におけるＲ^１と同義である。Ｒ^９としては、例えば、下記Ａ〜Ｃで示される基等の炭素数１〜１２の分枝状アルキレン基、下記Ｄで示される基等の分枝状ポリ（アルキレンオキシ）基または下記Ｅで示される基等の分枝状ポリシロキシ基等が挙げられる。ｊは、３または４である。
【００８９】
【化１０】

【００９０】
上記Ａにおいて、Ｒ^１０はメチル基、エチル基またはプロピル基等の低級アルキル基である。また、上記Ｄにおいて、ｐは１〜１０の整数である。
【００９１】
３〜４個のオキセタン環を有する化合物の一例としては、例示化合物３が挙げられる。
【００９２】
【化１１】

【００９３】
更に、上記説明した以外の１〜４個のオキセタン環を有する化合物の例としては、下記一般式（９）で示される化合物が挙げられる。
【００９４】
【化１２】

【００９５】
一般式（９）において、Ｒ^８は前記一般式（１９）のＲ^８と同義である。Ｒ^１１はメチル基、エチル基、プロピル基またはブチル基等の炭素数１〜４のアルキル基またはトリアルキルシリル基であり、ｒは１〜４である。
【００９６】
本発明に係るオキセタン化合物の好ましい具体例としては、以下に示す化合物がある。
【００９７】
【化１３】

【００９８】
上述したオキセタン環を有する各化合物の製造方法は、特に限定されず、従来知られた方法に従えばよく、例えば、パティソン（Ｄ．Ｂ．Ｐａｔｔｉｓｏｎ，Ｊ．Ａｍ．Ｃｈｅｍ．Ｓｏｃ．，３４５５，７９（１９５７））が開示している、ジオールからのオキセタン環合成法等がある。また、これら以外にも、分子量１０００〜５０００程度の高分子量を有する１〜４個のオキセタン環を有する化合物も挙げられる。これらの具体的化合物例としては、以下の化合物が挙げられる。
【００９９】
【化１４】

【０１００】
《非プロトン性極性溶媒》
本発明に用いられる非プロトン性極性溶媒について説明する。
【０１０１】
非プロトン性極性溶媒としては、ジメチルイミダゾリジノン、Ｎ−メチルピロリドン（ＮＭＰ）、Ｎ，Ｎ−ジメチルホルムアミド（ＤＭＦ）、Ｎ，Ｎ−ジメチルアセトアミド（ＤＭＡｃ）、ジメチルスルホキシド（ＤＭＳＯ）、スルホラン、２，４−ジメチルスルホラン、スルホレン、キノリン、イソキノリン、２，６−ルチジン、２，４，６−トリメチルピリジン、テトラメチル尿素、ジオキサン、テトラヒドロフラン（ＴＨＦ）、ヘキサメチルホスホリックトリアミド（ＨＭＰＡ）、Ｎ−メチルモルホリン（ＮＭｍ）、γ−ブチロラクトン（ＢＬｏ）、ニトロメタン、ニトリル基を有する化合物等が挙げられる。
【０１０２】
中でも、上記のニトリル基を有する化合物が特に好ましく用いられる。ニトリル基を有する化合物としては、例えば、アセトニトリル（ＡｃＮ）、ブチロニトリル、アクリロニトリル等が挙げられる。
【０１０３】
（非プロトン性極性溶媒の使用量）
非プロトン性極性溶媒の使用量は、本発明に記載の効果を好ましく発現し、且つ、色濁り等の防止する観点から、インク全量１００質量部に対して、０質量部〜２０質量部の範囲が好ましく、更に好ましくは、０質量部〜１０質量部であり、特に好ましくは０質量部〜５質量部である。
【０１０４】
《ラジカル重合性モノマー》
本発明に係るラジカル重合性モノマーとしては、各種（メタ）アクリレートモノマーが使用できる。例えば、イソアミルアクリレート、ステアリルアクリレート、ラウリルアクリレート、オクチルアクリレート、デシルアクリレート、イソミルスチルアクリレート、イソステアリルアクリレート、２−エチルヘキシル−ジグリコールアクリレート、２−ヒドロキシブチルアクリレート、２−アクリロイロキシエチルヘキサヒドロフタル酸、ブトキシエチルアクリレート、エトキシジエチレングリコールアクリレート、メトキシジエチレングリコールアクリレート、メトキシポリエチレングリコールアクリレート、メトキシプロピレングリコールアクリレート、フェノキシエチルアクリレート、テトラヒドロフルフリルアクリレート、イソボルニルアクリレート、２−ヒドロキシエチルアクリレート、２−ヒドロキシプロピルアクリレート、２−ヒドロキシ−３−フェノキシプロピルアクリレート、２−アクリロイキシエチルコハク酸、２−アクリロイキシエチルフタル酸、２−アクリロイキシエチル−２−ヒドロキシエチル−フタル酸、ラクトン変性可とう性アクリレート、ｔ−ブチルシクロヘキシルアクリレート等の単官能モノマー、トリエチレングリコールジアクリレート、テトラエチレングリコールジアクリレート、ポリエチレングリコールジアクリレート、トリプロピレングリコールジアクリレート、ポリプロピレングリコールジアクリレート、１，４−ブタンジオールジアクリレート、１，６−ヘキサンジオールジアクリレート、１，９−ノナンジオールジアクリレート、ネオペンチルグリコールジアクリレート、ジメチロール−トリシクロデカンジアクリレート、ビスフェノールＡのＥＯ付加物ジアクリレート、ビスフェノールＡのＰＯ付加物ジアクリレート、ヒドロキシピバリン酸ネオペンチルグリコールジアクリレート、ポリテトラメチレングリコールジアクリレート等の二官能モノマー、トリメチロールプロパントリアクリレート、ＥＯ変性トリメチロールプロパントリアクリレート、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、ジペンタエリスリトールヘキサアクリレート、ジトリメチロールプロパンテトラアクリレート、グリセリンプロポキシトリアクリレート、カウプロラクトン変性トリメチロールプロパントリアクリレート、ペンタエリスリトールエトキシテトラアクリレート、カプロラクタム変性ジペンタエリスリトールヘキサアクリレート等の三官能以上の多官能モノマーが挙げられる。
【０１０５】
尚、光（活性光線ともいう）照射した時のインク面の硬化収縮率を抑えるために、モノマー単体の硬化収縮率は１０％以下のものを用いることが好ましい。中でも単官能モノマーは、二官能以上のモノマーに比べて低収縮率であるとともに、インク画像に可撓性を持たせるため、カールの抑制、記録材料への密着性を得られるので好ましく用いることができる。
【０１０６】
本発明に係るラジカル重合性モノマーのインク中における好ましい含有量は、１０質量％〜５０質量％の範囲が好ましく、更に好ましくは、１０質量％〜３０質量％の範囲である。
【０１０７】
《光酸発生剤》
本発明に用いられる光酸発生剤について説明する。
【０１０８】
光酸発生剤としては、例えば、化学増幅型フォトレジストや光カチオン重合に利用される化合物が用いられる（有機エレクトロニクス材料研究会編・「イメ−ジング用有機材料」・ぶんしん出版（１９９３年）・１８７〜１９２ページ参照、技術情報協会・「光硬化技術」・２００１年、に紹介されている光酸発生剤）。本発明に好適な化合物の例を以下に挙げる。第１に、ジアゾニウム、アンモニウム、ヨードニウム、スルホニウム、ホスホニウムなどの芳香族オニウム化合物のＢ（Ｃ_６Ｆ_５）_４ ⁻、ＰＦ_６ ⁻、ＡｓＦ_６ ⁻、ＳｂＦ_６ ⁻、ＣＦ_３ＳＯ_３ ⁻塩を挙げることができる。対アニオンとしてボレート化合物をもつものが酸発生能力が高く好ましい。オニウム化合物の具体的な例を以下に示す。
【０１０９】
第２に、スルホン酸を発生するスルホン化物を挙げることができる。具体的な化合物を以下に例示する。第３に、ハロゲン化水素を光発生するハロゲン化物も用いることができる。第４に、鉄アレン錯体を挙げることができる。
【０１１０】
以下に化合物例を示すが、本発明はこれらに限定されない。
【０１１１】
【化１５】

【０１１２】
【化１６】

【０１１３】
【化１７】

【０１１４】
【化１８】

【０１１５】
《光ラジカル発生剤》
本発明に用いられる光発生剤としては、アリールアルキルケトン、オキシムケトン、アシルホスフィンオキシド、アシルホスホナート、チオ安息香酸Ｓ−フェニル、チタノセン、芳香族ケトン、チオキサントン、ベンジルとキノン誘導体またはケトクマリン類などの従来公知のものが使用できる。
【０１１６】
中でもアシルホスフィンオキシド、アシルホスホナートは、感度が高く、開始剤の光開裂により吸収が減少するため、インクジェット方式のように１色当たり５μｍ〜１５μｍの厚みを持つインク画像での内部硬化に特に有効である。
【０１１７】
具体的には、ビス（２，４，６−トリメチルベンゾイル）−フェニルホスフィンオキサイド、ビス（２，６−ジメトキシベンゾイル）−２，４，４−トリメチル−ペンチルホスフィンオキサイドなどが好ましい。
【０１１８】
また、高感度、安全性、臭気を考慮した選択では、１−ヒドロキシ−シクロヘキシル−フェニル−ケトン、２−メチル−１［４−（メチルチオ）フェニル］−２−モリホリノプロパン−１−オン、２−ヒドロキシ−２−メチル−１−フェニル−プロパン−１−オン、２−ベンジル−２−ジメチルアミノ−１−（４−モルホリノフェニル）−ブタノン−１が好適に用いられる。
【０１１９】
酸素重合阻害や感度を考慮した組み合わせでは、２−ベンジル−２−ジメチルアミノ−１−（４−モルホリノフェニル）−ブタノン−１と１−ヒドロキシ−シクロヘキシル−フェニル−ケトンとの組み合わせ、１−ヒドロキシ−シクロヘキシル−フェニル−ケトンとベンゾフェノンとの組み合わせ、２−メチル−１［４−（メチルチオ）フェニル］−２−モリホリノプロパン−１−オンまたは２−メチル−１［４−（メチルチオ）フェニル］−２−モリホリノプロパン−１−オンとジエチルチオキサントンもしくはイソプロピルチオキサントンとの組み合わせ、ベンゾフェノンと三級アミノ基を持つアクリル酸誘導体との組み合わせ、三級アミンの添加などが効果的である。
【０１２０】
《色材》
本発明に係るインク組成物を着色する場合は、色材を添加する。色材としては、重合性化合物の主成分に溶解または分散できる各種色材を使用することができるが、耐候性の観点から顔料が好ましい。
【０１２１】
本発明で好ましく用いることのできる顔料を、以下に列挙する。
Ｃ．Ｉ Ｐｉｇｍｅｎｔ Ｙｅｌｌｏｗ−１、３、１２、１３、１４、１７、８１、８３、８７、９５、１０９、４２、
Ｃ．Ｉ Ｐｉｇｍｅｎｔ Ｏｒａｎｇｅ−１６、３６、３８、
Ｃ．Ｉ Ｐｉｇｍｅｎｔ Ｒｅｄ−５、２２、３８、４８：１、４８：２、４８：４、４９：１、５３：１、５７：１、６３：１、１４４、１４６、１８５、１０１、
Ｃ．Ｉ Ｐｉｇｍｅｎｔ Ｖｉｏｌｅｔ−１９、２３、
Ｃ．Ｉ Ｐｉｇｍｅｎｔ Ｂｌｕｅ−１５：１、１５：３、１５：４、１８、６０、２７、２９、
Ｃ．Ｉ Ｐｉｇｍｅｎｔ Ｇｒｅｅｎ−７、３６、
Ｃ．Ｉ Ｐｉｇｍｅｎｔ Ｗｈｉｔｅ−６、１８、２１、
Ｃ．Ｉ Ｐｉｇｍｅｎｔ Ｂｌａｃｋ−７、
また、本発明において、プラスチックフィルムのような透明基材での色の隠蔽性を上げるために、白インクを用いることが好ましい。特に、軟包装印刷、ラベル印刷においては、白インクを用いることが好ましいが、吐出量が多くなるため、前述した吐出安定性、記録材料のカール・しわの発生の観点から、自ずと使用量に関しては制限がある。
【０１２２】
上記顔料の分散には、例えば、ボールミル、サンドミル、アトライター、ロールミル、アジテータ、ヘンシェルミキサ、コロイドミル、超音波ホモジナイザー、パールミル、湿式ジェットミル、ペイントシェーカー等を用いることができる。また、顔料の分散を行う際に、分散剤を添加することも可能である。分散剤としては、高分子分散剤を用いることが好ましく、高分子分散剤としてはＡｖｅｃｉａ社のＳｏｌｓｐｅｒｓｅシリーズが挙げられる。また、分散助剤として、各種顔料に応じたシナージストを用いることも可能である。これらの分散剤及び分散助剤は、顔料１００質量部に対し、１質量部〜５０質量部添加することが好ましい。分散媒体は、溶剤または重合性化合物を用いて行うが、本発明に用いる照射線硬化型インクでは、インク着弾直後に反応・硬化させるため、無溶剤であることが好ましい。溶剤が硬化画像に残ってしまうと、耐溶剤性の劣化、残留する溶剤のＶＯＣの問題が生じる。よって、分散媒体は溶剤では無く重合性化合物、その中でも最も粘度の低いモノマーを選択することが分散適性上好ましい。
【０１２３】
顔料の分散は、顔料粒子の平均粒径を０．０８μｍ〜０．５μｍとすることが好ましく、最大粒径は０．３μｍ〜１０μｍ、好ましくは０．３μｍ〜３μｍとなるよう、顔料、分散剤、分散媒体の選定、分散条件、ろ過条件を適宜設定する。この粒径管理によって、ヘッドノズルの詰まりを抑制し、インクの保存安定性、インク透明性及び硬化感度を維持することができる。
【０１２４】
本発明に係るインクにおいては、色材濃度としては、インク全体の１質量％〜１０質量％であることが好ましい。
【０１２５】
《添加剤等》
本発明に係るインクには、上記説明した以外に様々な添加剤を用いることができる。例えば、インク組成物の保存性を高めるため、重合禁止剤を２００ｐｐｍ〜２００００ｐｐｍ添加することができる。紫外線硬化型のインクは、加熱、低粘度化して射出することが好ましいので、熱重合によるヘッド詰まりを防ぐためにも重合禁止剤を入れることが好ましい。この他にも、必要に応じて、界面活性剤、レベリング添加剤、マット剤、膜物性を調整するためのポリエステル系樹脂、ポリウレタン系樹脂、ビニル系樹脂、アクリル系樹脂、ゴム系樹脂、ワックス類を添加することができる。記録媒体との密着性を改善するため、極微量の有機溶剤を添加することも有効である。この場合、耐溶剤性やＶＯＣの問題が起こらない範囲での添加が有効であり、その使用量は０．１％〜５％の範囲であり、好ましくは０．１％〜３％である。
【０１２６】
これらの各種モノマー、色材としては、世界特許９９／２９７８７号、特開２００１−２２０５２６号に開示されているものなどが使用できる。その他、開始剤、添加剤等もこれらの文献を参考にできる。
【０１２７】
本発明に係る光硬化性インクとしては、カチオン重合性のインク、ラジカル重合性のインクを各々単独で使用することが可能であるが、両者を混合し、ハイブリッドインクとして使用することも可能である。
【０１２８】
本発明のインクジェットヘッドは、これらカチオン重合性またはラジカル重合性のインクに適しているが、特にカチオン重合性インクを用いた時に、その優れた耐久性を発揮することができる。
【０１２９】
【発明の実施の形態】
以下、本発明の実施の形態について、図面を参照しながら説明をするが、本発明はこれらに限定されない。
【０１３０】
図１は、本発明の実施の形態におけるインクジェット用インク送液ポンプ断面模式図である。図１において、１は円筒室２を形成した基板であり、円筒室２の内周面２ａは円形で半円周より大きく全円周よりは小さな範囲で形成され、内周面２ａが形成されていない部分は開口部２ｂとなっている。３は弾性材料からなるチューブであり、円筒室２の内周面２ａに添わせてリング状に配置すると共に、その両端を基板１の外部に引き出して流入口３ａと流出口３ｂを構成している。基板１は例えばＮＢＲ等のゴム系材料やＡＢＳ等の合成樹脂の成形品で構成され、またチューブ３は本発明に係る前記したチューブが使用される。
【０１３１】
４はチューブ３の内側に配置されたリング状の加圧部材であって、内リング４１と外リング４２の二重構造となっており、加圧部材４の内リング４１は摩擦係数の小さい剛体材料、例えばフッ素樹脂系の合成樹脂成形品で構成され、外リング４２はゴムなどの摩擦係数の大きい弾性材料の成形品で構成されている。図２に示すように、内リング４１と外リング４２は断面が長方形で丁度重なるような寸法で形成されており、内リング４１の外周面４１ｂに設けた突条４１ｃを外リング４２の内周面４２ａに設けた周溝４２ｃに嵌めることによって、外リング４２は自由に回転できる状態で内リング４１に保持されている。尚、これとは逆に外リング４２に突条を、内リング４１に周溝を設けてもよく、また突条と周溝をあり溝式の形状とすることもできる。
【０１３２】
５は加圧部材４の内側に配置された偏心ローター、６は偏心ローター５が取り付けられている回転軸であって、偏心ローター５の先端５ａが内リング４１の内周面４１ａに摺接しながら回転して加圧部材４を円筒室２の内周面２ａ側に押圧し、加圧部材４を内周面２ａに沿って円運動させるように構成されている。尚、基板１の背面側には回転軸６を駆動するための減速機付きモータなどが配置されており、また手前側には蓋が設けられるが、これらは図示してない。
【０１３３】
加圧部材４の外リング４２の外周面４２ｂの半径は、円筒室２の半径からチューブ３の肉厚の２倍以上を差し引いた寸法に選定されている。また、回転軸６の軸心から偏心ローター５の先端５ａまでの距離と内リング４１の内周面４１ａから外リング４２の外周面４２ｂまでの寸法の和は、偏心ローター５の先端５ａによって加圧部材４が基板１の内周面２ａ側に押された場合に、外リング４２によってチューブ３が押しつぶされて内部の流路が完全に閉塞されるように選定されている。
【０１３４】
図示の例は上述のように構成されているので、偏心ローター５を矢印のように時計方向に回転させて加圧部材４を円運動させると、加圧部材４に押圧されて生ずるチューブ３の閉塞箇所も時計方向に移動し、チューブ内部の流体が流出口３ｂから吐出されると同時に流入口３ａから吸入されてポンプ作用が行われる。
【０１３５】
図３は、本発明の実施の形態における別のインクジェット用インク送液ポンプ断面模式図である。尚、図１、２と同一の部分は同じ符号で示してある。
【０１３６】
図３において、１５は上記の回転止め機構として設けられた支持手段であって、基板１に固定された支軸１６と加圧部材４の内リング４１に形成された穴１７との組み合わせで内リング４１を円筒室２内に支持しており、この例では図示の姿勢における縦の中心線上の上下２箇所に支持手段１５が設けられている。支軸１６の径は必要な強度が得られる寸法に選定され、穴１７は丸穴でその径は加圧部材４がチューブ３に対する押圧作用を支障なく発揮できるだけの運動の自由度が得られる寸法に選定されている。尚、図４とは逆に支軸１６を内リング４１に、穴１７を基板１にそれぞれ設けてもよい。また穴１７は必ずしも丸穴である必要はなく、加圧部材４の運動の自由度が確保される形状と大きさであれば円形以外の適宜の形状を採用することができる。
【０１３７】
このような構成において偏心ローター５を回転させると、内リング４１は支軸１６と穴１７の組み合わせからなる支持手段１５で自転を阻止されているため連続して同一方向に自転を続けることができず、偏心ローター５が下向きの時には主として上部の支持手段１５を支点とした振り子運動が円運動に加わった状態となり、また偏心ローター５が上向きの時には主として下部の支持手段１５を支点とした振り子運動が円運動に加わった状態となるが、全体としてはほぼ同じ姿勢のままでチューブ３を順次押圧する円運動だけが行われることになる。従って、上述したように内リング４１と外リング４２との間がスリップし、更に内リング４１自体が連続して同じ方向に自転することもなくなるため、外リング４２に加わる回転力は極めて小さくなってチューブ３が引っ張られる現象はほとんど生じない。
【０１３８】
尚、このような支持手段１５を設けた場合には、偏心ローター５が流出口３ｂ側から流入口３ａ側に移動する際に下部の支持手段１５を支点とした加圧部材４の振り子運動が生ずる。このため、加圧部材４の全体が一体に形成されていて外リング４２を設けていない従来例の場合には、加圧部材４で押圧されているチューブ３の流出口３ｂに近い部分が、振り子運動に伴う加圧部材４の外周面の移動に伴って流入口３ａ側に引きずられる現象が起きやすく、チューブ３の一部が開口部２ｂに突出して腰折れ部３ｃを生ずるに至り、チューブの損傷や流量低下を招くことが多い。
【０１３９】
この現象は加圧部材４とチューブ３の間を十分潤滑していても生じやすいのであるが、この形態のように内リング４１に対して滑りやすい外リング４２を加圧部材４に設けたものでは、チューブ３に接触している外リング４２の外周面４２ｂが振り子運動に伴ってチューブ３と共に流入口３ａ側に移動しようとしても、その前に両リング４１，４２の間で滑りが生じて外周面４２ｂは移動しない。即ち、外リング４２による引きずり現象が両リング４１，４２間の滑りにより吸収された形になって腰折れ部３ｃは発生しなくなるのであり、この部分でチューブが損傷したり、流量が低下したりするという問題もない。
【０１４０】
比較として、既存のチューブ送液ポンプの断面模式図を、図４に示した。
【０１４１】
【実施例】
以下、実施例を挙げて本発明を具体的に説明するが、本発明の実施態様はこれらに限定されるものではない。
【０１４２】
実施例１
《インクジェット用インク送液ポンプの作製》
表１に示すような構成部材を用いて、図１、図３及び図４に示したような形態を有する、インクジェット用インク送液ポンプ１（図１：本発明）、２（図３：本発明）、インクジェット用インク送液ポンプ３（図４：比較例）を各々作製した。
【０１４３】
《インクジェット用インク送液チューブの調製》
重合時の触媒の中和剤として表１に示した炭酸カルシウムまたは炭酸マグネシウムを用いて得られたポリプロピレンを使用して、本発明のインクジェット用インク送液チューブを作製した。重合時の触媒の中和剤をステアリン酸カルシウムとする以外は、本発明と同様にして比較例のインクジェット用インク送液チューブを作製した。
【０１４４】
《インクジェットインクの調製》
下記のように、マゼンタ顔料分散物を作製し、次いで、得られたマゼンタ顔料分散物を用いて、マゼンタインク（インク浸漬試験においても、浸漬液として使用する）を調製した。
【０１４５】
（ａ）マゼンタ顔料分散物の調製
以下の配合でマゼンタ顔料分散物を得た。
【０１４６】

上記で得られたマゼンタ顔料分散物を用い、下記の配合を行い、０．８μｍのメンブレンフィルターにて濾過、５０℃に加熱しながら減圧条件下で脱水を行い、マゼンタインクを得た。
【０１４７】
（マゼンタインクの組成）
マゼンタ顔料分散物 １７質量部
アロンオキセタンＯＸＴ−２２１（東亜合成） ７０質量部
セロキサイド２０２１Ｐ（ダイセルＵＣＢ） ３０質量部
ＵＶＩ−６９９０（ダウケミカル製、光酸発生剤） ５質量部
《インク送液用チューブのインク浸漬評価》
得られたインク送液用チューブの各々について、上記のマゼンタインクを浸漬液として用い、前述のインク浸漬試験を行い、インク送液用チューブの質量変化率（％）、インク濁度変化率を求めた。得られた結果は表２に示す。
【０１４８】
《インクジェットプリンタを用いた連続出射試験》
インクジェットヘッドを接続し、下記のようにして連続出射試験を行った。
【０１４９】
上記作製したインク送液用ポンプとインク送液用チューブを、各々インクジェットプリンタ（オリンパス社製ＰＪ５４００）に装着し、上記マゼンタインク（インク浸漬試験用にも使用）をインク温度５０℃に保ちながら、連続印字試験を行い、インク出射精度、インクジェットヘッドノズル詰まりを評価した。
【０１５０】
得られた結果を表２に示す。
【０１５１】
【表１】

【０１５２】
【表２】

【０１５３】
上表により、比較例に対し本発明の構成により、インク送液用チューブの質量変化率（％）、インク濁度変化率が改善され、インクジェットプリンタを用いた連続出射試験においても良好な結果を示すことが分かる。
【０１５４】
実施例２
インク吐出量を表３に示す通り変更した以外は実施例１と同様な評価を実施した。結果を表４に示す。
【０１５５】
【表３】

【０１５６】
【表４】

【０１５７】
上表より、インク吐出量を本発明の構成にすることにより、実施例１を再現し良好な結果が得られた。
【０１５８】
【発明の効果】
本発明により、光硬化性インクに対する耐蝕性が向上し、長時間使用してもインク詰まりや、インク漏れが起こらず、インク滴吐出精度も安定に確保でき、インク感度への影響も軽減できる新規な記録器具を提供することができる。
【図面の簡単な説明】
【図１】本発明の実施の形態におけるインクジェット用インク送液ポンプ断面模式図である。
【図２】同上の加圧部材の断面図である。
【図３】本発明の実施の形態における別のインクジェット用インク送液ポンプ断面模式図である。
【図４】比較例の既存送液ポンプ断面模式図である。
【符号の説明】
１ 基板
２ 円筒室
２ａ 内周面
３ チューブ
４ 加圧部材
５ 偏心ローター
１５ 支持手段（回転止め機構）
１６ 支軸
１７ 穴
４１ 内リング
４２ 外リング
５１ チューブ受け
５２ ローラー
５３ ローター
５４ シャフト[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an ink-feeding member for inkjet and an ink-jet recording method using the ink-feeding member for inkjet.
[0002]
[Prior art]
Conventionally known ink jet recording methods include a method using various inks such as an aqueous ink, an oil-based ink, a solvent ink, and a photo-curable ink (for example, an ultraviolet-curable ink). Even when these inks are used, as the constituent members of the inkjet recording device used in inkjet recording, the above-described aqueous ink, oil-based ink, and solvent ink have been used in many printers. (See, for example, Patent Documents 1, 2, and 3). 2. Description of the Related Art In recent years, an ink jet recording method using a photocurable ink has attracted attention as a method for forming an image even on a substrate having poor ink absorption. These include a solvent type in which a reactive monomer is diluted with water, an aqueous solvent, and various organic solvents, and a solventless type in which no solvent remains after curing. In recent years, solvent-free ink has attracted attention due to the demand for VOC-free ink. Photocurable inks that cure ink by light such as ultraviolet rays or EB (ultraviolet rays, near infrared rays, electron beams, etc.) include radically polymerizable inks mainly composed of acrylate monomers and epoxy monomer or oxetane monomers. Cationic polymerizable inks are known. However, acrylate monomers, epoxy monomers, oxetane monomers, etc., exhibit properties that are significantly different from those of diluent solvents used in conventional aqueous inks, oil-based inks, and solvent inks. Had many problems. Monomers have properties close to those of plasticizers used as plastic additives, and are easily compatible with many plastics. Conventionally, various kinds of resins, glass, ceramics, metals and the like are generally used as constituent materials for recording instruments of such a recording apparatus, and among resins, polypropylene has a good chemical resistance and a good impact strength. In addition, because of its good fluidity, it can be easily molded into a thin or complicated-shaped mold, and furthermore, since it is possible to obtain transparency, it is often used for the recording instrument. Was. However, even in a recording device using polypropylene having such excellent properties, since these monomer components are much easier to dissolve and swell the components of the inkjet recording device than conventional diluting solvents, for example, Due to the ink staying for a long period of time, the recording apparatus is melted and leached substances such as fibrous floating substances formed in the ink are formed in the ink, which clog the recording means and the ink supply member, and There has been a problem that the ejection of the ink becomes unstable, the ink is cut off, or in a severe case, the recording becomes impossible due to the inability to eject the ink. Above all, the photocurable ink has a high viscosity, and it is necessary to obtain ejection stability by heating the ink and lowering the viscosity, but the problem that the corrosion resistance of the ink is further required by the heating. In addition, it has been pointed out that a problem peculiar to the photocurable ink is that the curing sensitivity is reduced by light depending on the eluted component. Among the curable inks, particularly, cationically polymerizable inks using epoxy monomers, oxetane monomers, vinyl ether monomers, etc., have high resistance to various recording devices, particularly ink jet ink supply tubes, and are hardened. There is a problem that sensitivity is easily affected.
[0003]
[Patent Document 1]
JP 2001-301160 A
[0004]
[Patent Document 2]
JP 2001-301178 A
[0005]
[Patent Document 3]
Japanese Patent Publication No. 6-39166
[0006]
[Problems to be solved by the invention]
An object of the present invention is to improve the corrosion resistance to photocurable ink, prevent ink clogging and ink leakage even when used for a long time, ensure stable ink droplet ejection accuracy, and reduce the effect on ink sensitivity. It is to provide a new recording device that can be used.
[0007]
[Means for Solving the Problems]
The above object of the present invention has been achieved by the following constitutions.
[0008]
1. In an ink-feeding member for ink-jet using a photo-curable ink, a tube pump is used to feed the ink from the ink storage unit to the ink-jet head, and a tube pump for crushing the tube when the photo-curable ink is fed. Contact area A between pressure member and tube (cm²) And tube tube area B (cm²), Wherein the ratio A / B is 10 or more and 150 or less.
[0009]
2. In an ink-feeding member for ink-jet using a photo-curable ink, a tube pump is used to feed the ink from the ink storage unit to the ink-jet head, and a tube pump for crushing the tube when the photo-curable ink is fed. Contact area A between pressure member and tube (cm²) And the ratio A / C of the ink discharge amount C (ml / min) is 0.1 or more and 20 or less.
[0010]
3. In an ink-feeding member for ink-jet using a photocurable ink, a mass change rate of a liquid-feeding tube for feeding the ink from an ink storage unit to an ink-jet head by a UV ink immersion test is less than 50%. 3. The ink-feeding member for inkjet according to the above item 1 or 2.
[0011]
4. 4. An ink-jet recording method, comprising using the ink-feeding member for ink-jet according to any one of the above items 1 to 3.
[0012]
5. 5. The ink jet recording method according to the item 4, wherein a cationically polymerizable ink is used as the photocurable ink.
[0013]
Hereinafter, the present invention will be described in detail.
《Ink feeder for inkjet ink》
The material of the tube for sending the liquid from the ink storage unit to the ink jet head will be described. The tube according to the present invention has a mass change rate of less than 50% in an ink immersion test. In the present invention, an immersion test is performed using the ink used in the inkjet recording apparatus at the temperature used. That is, if the temperature to be used is 60 ° C., the tube to be used is immersed in the ink at 60 ° C. for one week, and the mass change rate is measured.
[0014]
Tubes that can be used include FEP (tetrafluoroethylene-hexafluoropropylene copolymer), PFA (perfluoroalkoxy resin; tetrafluoroethylene-pearlluorinated alkyl vinyl ether copolymer), TFE (tetrafluoroethylene), perfluoroelastomer, etc. Perfluoro-type fluororesin, PE, PP, ethylene propylene rubber (EPM, EPDM), silicone rubber (Q), chlorosulfonated rubber (CSM), chlorinated polyethylene (CM), fluororubber (FKM), FEPM, FFKM And polyesters such as PES and PBT, polyacetals, PI (polyimide) and the like.
[0015]
Here, the classification and the name of the synthetic rubber and the like conformed to the classification according to JIS K6397.
[0016]
Among these materials, particularly preferred as the tube are PE, PP, TFE (tetrafluoroethylene), PFA (perfluoroalkoxy resin; tetrafluoroethylene-pearlluorinate alkyl vinyl ether copolymer), and FEP (tetrafluoroethylene-hexaene). Fluoropropylene copolymer), FKM, FFKM, FEPM, PI (polyimide) and the like.
[0017]
Fluoro rubbers such as FKM, FEPM and FFKM, and polypropylene are preferably FFKM which is a rubber-like copolymer in which all side chains are fluoro and perfluoroalkyl or perfluoroalkoxy groups (consisting of C, F, O ). FKM has a fluorine content of 66 to 70%, but preferably 80% or more. FFKM is marketed as perfluoroelastomers such as Daikin Perflo manufactured by Daikin and Kalrez manufactured by DuPont. The hardness is preferably 80 degrees or less. The hardness in the present invention is a hardness indicated in JIS-6301-1962 standard.
[0018]
In addition, as a polypropylene, a polypropylene obtained by adding calcium carbonate or magnesium carbonate as a neutralizer of a catalyst at the time of polymerization is used as a main component, and various fillers, dispersants and the like are added to this as necessary. It is formed using various known molding methods. Particularly preferred as polypropylene are those obtained by adding calcium carbonate or magnesium carbonate as a neutralizing agent of a catalyst at the time of polymerization, for example, a catalyst known as Ziegler-Natta catalyst or the like. Except for adding, it can be obtained by using a known method known as a method for producing polypropylene. The catalyst neutralizing agent is added to treat the catalyst residue. If there is a catalyst residue, there is a problem that the obtained polypropylene has corrosiveness. As a neutralizing agent for a catalyst such as a Ziegler-Natta catalyst, calcium stearate is generally used. The action of these calcium oxides or magnesium carbonates is not necessarily clear, but the polypropylene obtained by using them as a catalyst neutralizer during polymerization has extremely improved ink resistance as described later. One or more of these calcium carbonates or magnesium carbonates are appropriately selected and used. As an addition method, it is preferably granular, and an addition of about 0.1 to 1.5 phr (per hundred resin) is good.
[0019]
The inner diameter of the tube is 1 to 50 mm, preferably 2 to 20 mm, more preferably 5 to 15 mm.
[0020]
The liquid supply pump for supplying liquid from the ink storage unit to the ink jet head according to the present invention is a tube pump, and further has a cylindrical chamber with a circular inner peripheral surface provided on the substrate, and is elastically attached to the inner peripheral surface. A tube pump, in which a tube made of a material is arranged, and a ring-shaped pressurizing member provided inside the tube is circularly moved along the inner peripheral surface of the cylindrical chamber to sequentially press the tubes in one direction to perform a pumping operation ( For example, see JP-A-5-133350, JP-A-11-13648, and JP-A-11-62854. In addition, the contact area A (cm) between the pressure member and the tube that crush the tube during ink feeding.²) And tube tube area B (cm²) Is 10 or more and 150 or less, preferably 15 or more and 100 or less.
[0021]
On the other hand, the amount of ink discharged by the tube pump is 5 to 50 ml / min, preferably 10 to 40 ml / min, more preferably 20 to 30 ml / min. Contact area A (cm²) And the ink discharge amount C (ml / min) A / C is 0.1 or more and 20 or less, preferably 0.2 or more and 15 or less.
[0022]
By satisfying these conditions, when the photocurable ink is fed using a tube formed mainly of polypropylene obtained by adding calcium carbonate or magnesium carbonate as a catalyst neutralizer at the time of polymerization, the ink becomes It was found that the ejection accuracy was greatly improved, ink clogging and ink leakage did not occur, and the effect on ink sensitivity was very small.
[0023]
<< Components of inkjet head >>
The components of the inkjet head used in the present invention will be described.
[0024]
The components of the inkjet head used in the present invention include conventionally known components of the inkjet head. For example, a manifold, an ink tube, a filter, a piezoelectric ceramic substrate, a lid member, an adhesive, an O-ring, Protective films, electrode films, nozzle plates, NWC (non-wet coating) materials, and the like can be given.
[0025]
Here, the constituent member of the inkjet head used in the present invention refers to a member that forms a portion that comes into contact with the photocurable ink when the photocurable ink is filled (at the time of the ink immersion test).
[0026]
The details of the ink jet head including these components will be described later.
(Materials for components)
As described above, the materials (organic compounds, polymer materials, inorganic compounds, metal compounds, etc.) used for producing the components constituting the ink jet head used in the present invention have a mass change rate of −0 after the ink immersion test. It is preferably in the range of 8.8% by mass to 8.0% by mass, and more preferably, the mass change rate is in the range of -0.2% by mass to 5.0% by mass. The details of the ink immersion test will be described later.
[0027]
Each constituent member of the ink jet head used in the present invention is, after the ink immersion test, as a material for adjusting so as to fall within the range of the above-mentioned mass change rate, for the photocurable ink according to the present invention, a so-called anti-resistance. Materials having high ink properties are preferable. For example, conventionally known polyethylene, polypropylene, PET (polyethylene terephthalate), PBT (polybutylene terephthalate), nylon, TFE (tetrafluoroethylene), PFA (perfluoroalkoxyethylene copolymer), Examples include FEP (fluorinated ethylene propylene), perfluoroelastomer, polyparaxylene, epoxy adhesive, SUS, and PI (polyimide). Of these, PET (polyethylene terephthalate), PBT (polybutylene terephthalate), nylon, TFE (tetrafluoroethylene), PFA (perfluoroalkoxyethylene copolymer), FEP (fluoroethylene propylene), Fluoroelastomer, SUS, PI (polyimide) and the like.
[0028]
On the other hand, when used as a constituent member of the ink jet head of the present invention, examples of unfavorable members include acrylics such as ABS, PEI, PVC, various plastics containing a plasticizer, and elastomers such as SBR, NBR and EPDM. .
[0029]
When cationically polymerizable monomers, for example, oxirane group-containing monomers, oxetane-containing monomers, and vinyl ethers are used as the ink, the monomers are easily impregnated and swelled, so that deformation occurs, and particularly, elastomers and plasticizer-containing plastics are used. Have problems such as easy swelling and easy elution of the plasticizer.
[0030]
(adhesive)
As the adhesive, an epoxy-based or urethane-based adhesive is preferable, and among them, an epoxy-based adhesive is preferably used. As the epoxy-based adhesive, for example, a two-pack normal-temperature curing type EP-330, EP-331 or 1500 manufactured by Cemedine Co., Ltd. can be used. As the urethane-based adhesive, Alonmelt R-2300 manufactured by Toa Gosei Co., Ltd., and Penguin Cement # 990A manufactured by Sunstar Giken Co., Ltd. can be used.
[0031]
In the present invention, when an epoxy-based adhesive is used, when a two-component curable member is used as the epoxy adhesive, it is necessary to select a material and curing conditions so that the mass change rate described in claim 1 is achieved. is there.
[0032]
When curing failure occurs during curing, uncured amines are eluted, the mass change rate after ink immersion becomes less than -0.8% by mass, and the eluted amines such as pigments in the ink Problems such as aggregation of the coloring material are caused, and when the cationically polymerizable ink is used, sensitivity is reduced.
[0033]
(Protective film)
As a material of the protective film, PI (polyimide), PMMA (polymethyl methacrylate), and polyparaxylylene can be preferably used.
[0034]
(Manifold)
As the material of the manifold, PET (polyethylene terephthalate), PBT (polybutylene terephthalate), and nylon can be preferably used.
[0035]
(filter)
As a material for the filter, SUS or nylon can be preferably used.
[0036]
(Nozzle plate)
As a material of the nozzle plate, PI (polyimide) or SUS can be preferably used.
[0037]
(NWC (Non-wet coating))
As NWC for imparting ink repellency to the nozzle plate, TFE, PFA, FEP, fluorine-modified PI (polyimide) and the like are preferable.
[0038]
(FPC (Flexible Print Circuit))
As a material of the FPC (flexible print circuit), PI (polyimide) can be preferably used.
[0039]
(External members such as covers)
POM (polyoxymethylene), HDPE (high-density polyethylene), and PPE (polyphenylene ether) can be preferably used as a material of a cover as an external member for protecting the inkjet head.
[0040]
<< PI (polyimide) >>
Here, a description will be given of PI (polyimide) which is preferably used for a constituent member suitable for the present invention.
[0041]
The solvent-soluble PI (polyimide) used in the present invention is specifically described in the following literature. E. FIG. S. Moyer, D .; K. Mohanty, C.M. A. Arnold, J .; E. FIG. McGrath; "Synthesis and Characterization of Soluble Polyimide Homo-and Copolymers"; Polymeric Materials; Science & Engineering Proceedings of Medicine; 202-205; Spring 1989. M. E. FIG. Rodgers, C.A. A. Arnold, J .; E. FIG. McGrath; "Soluble, Processable Polyimide Homepolymers Copolymers"; Polymer Preprints, ACS Divisionof Polymer Chemistry; V30-1; p. 296; Y. Oishi, M .; Xie, M .; Kakimoto, Yoshio; "Syntheses and Characterizationof Soluble Arumatic Polyamides and Polyimides from 1,1- (Bis (4-Aminophenyl)) - 2,2-diphenylethylene"; Polymeric Materials: Science & Engineering Proceedings of ACS Division of Polymeric Materials; V60; p. 757-761; Spring 1989. F. W. Harris, Y .; Sakaguchi; "SolubleAromatic Polyimides Derived from NewPhenylated Diamines": Polymeric Materials; Science & Engineering, Professionals. 187-192; Spring 1989.
The polyimide used in the present invention is synthesized from tetracarboxylic dianhydride and diamine. The tetracarboxylic dianhydride used is not particularly limited, but examples of the acid dianhydride useful in practicing the present invention include pyromellitic dianhydride, 3,3 ', 4,4'-biphenyl Tetracarboxylic dianhydride, 3,3 ', 4,4'-benzophenonetetracarboxylic dianhydride, 3,3', 4,4'-diphenylsulfonetetracarboxylic dianhydride, 3,3 ', 4 4,4'-diphenylethertetracarboxylic dianhydride, 3,3 ', 4,4'-diphenylmethanetetracarboxylic dianhydride, 2,3,3', 4'-biphenyltetracarboxylic dianhydride, 2, 3,3 ', 4'-diphenyl ether tetracarboxylic dianhydride, 2,3,3', 4'-benzophenone tetracarboxylic dianhydride, 2,3,6,7-naphthalene tetracarboxylic dianhydride, 1,4 5,7-naphthalenetetracarboxylic dianhydride, 1,2,5,6-naphthalenetetracarboxylic dianhydride, 2,2-bis (3,4-dicarboxyphenyl) propanoic dianhydride, 2, 2-bis (3,4-dicarboxyphenyl) hexafluoropropanoic dianhydride, 4,4'-bis (3,4-dicarboxyphenyl) diphenyl sulphidic dianhydride, 1,3-diphenylhexafluoropropane -3,3,4,4-tetracarboxylic dianhydride, 1,4,5,6-naphthalenetetracarboxylic dianhydride, 2,2 ', 3,3'-diphenyltetracarboxylic dianhydride, 3,4,9,10-berylene tetracarboxylic dianhydride, bis (3,4-dicarboxyphenyl) ether dianhydride, naphthalene-1,2,4,5-tetracarboxylic dianhydride , Naphthalene-1,4,5,8-tetracarboxylic dianhydride, decahydronaphthalene-1,4,5,8-tetracarboxylic dianhydride, 4,8-dimethyl-1,2,3,3 5,6,7-hexahydronaphthalene-1,2,5,6-tetracarboxylic dianhydride, 2,6-dichloronaphthalene-1,4,5,8-tetracarboxylic dianhydride, 2,7 Dichloronaphthalene-1,4,5,8-tetracarboxylic dianhydride, 2,3,6,7-tetrachloronaphthalene-1,4,5,8-tetracarboxylic dianhydride, phenanthrene-1, 8,9,10-tetracarboxylic dianhydride, cyclopentane-1,2,3,4-tetracarboxylic dianhydride, pyrrolidine-2,3,4,5-tetracarboxylic dianhydride, pyrazine- 2,3,5,6-tetracarboxylic acid Dianhydride, 2,2-bis (2,3-dicarboxyphenyl) propanoic dianhydride, 1,1-bis (2,3-dicarboxyphenyl) ethaneic dianhydride, 1,1-bis ( 3,4-dicarboxyphenyl) ethanoic dianhydride, bis (2,3-dicarboxyphenyl) methane dianhydride, and benzene-1,2,3,4-tetracarboxylic dianhydride; Derivatives and mixtures thereof.
[0042]
Tetracarboxylic dianhydrides particularly advantageous for obtaining solvent-soluble polyimides are not particularly limited, but include biphenyltetracarboxylic dianhydride, benzophenonetetracarboxylic dianhydride, 4,4 '-[2,2, 2-trifluoro-1- (trifluoromethyl) ethylidene] bis (1,2-benzene) dicarboxylic dianhydride, bis (dicarboxyphenyl) ether dianhydride, bicyclo [2.2.2] oct-7 -Ene-2,3,5,6-tetracarboxylic dianhydride and the like. These can be used alone or as a mixture of two or more to form a polyimide composition.
[0043]
Although there is no particular limitation on the diamine used, preferred examples of the diamine in the practice of the present invention include 4,4′-diaminodiphenyl ether, 3,3′-dimethyl-4,4′-diaminobiphenyl, and 3,3 ′. -Dimethoxy-4,4'-diaminobiphenyl, 4,4'-diaminoparaterphenyl, 4,4'-bis (4-aminophenoxy) -biphenyl, 4,4'-diaminodiphenylsulfone, 3,3'- Diaminodiphenyl sulfone, bis [4- (4-aminophenoxy) phenyl] sulfone, bis [4- (3-aminophenoxy) phenyl] sulfone, bis [2- (aminophenoxy) phenyl] sulfone, 1,4-bis ( 4-aminophenoxy) benzene, 2,2'-dichloro-4,4'-diamino-5,5'-dimethoxybiphenyl 2,2 ', 5,5'-tetrachlorobenzidine, 9,10-bis (4-aminophenyl) anthracene, o-tolidine sulfone, 1,3-bis (4-aminophenoxy) benzene, 1,3-bis (3-aminophenoxy) benzene, 1,4-bis (4-aminophenyl) benzene, bis [4- (aminophenoxy) phenyl] ether, 4,4'-diaminodiphenylmethane, bis (3-ethyl-4-amino Phenyl) methane, bis (3-methyl-4-aminophenyl) methane, bis (3-chloro-4-aminophenyl) methane, 2,2 ', 5,5'-tetrachloro-4,4'-diaminobiphenyl 4,4'-diaminodiphenyl sulfide, 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4 ' Diaminodiphenylmethane, 4,4'-diaminooctafluorobiphenyl, metaphenylenediamine, 2,2-bis [(4-aminophenoxy) phenyl] propane, 2,2-bis [4- (4-aminophenoxy) phenyl] hexa Fluoropropane, 2,2-bis (4-aminophenyl) propane, 2,2-bis (4-aminophenyl) hexafluoropropane, 2,2-bis (3-hydroxy-4-aminophenyl) propane, 2, 2-bis (3-hydroxy-4-aminophenyl) hexafluoropropane, 9,9-bis (4-aminophenyl) -10-hydroanthracene, orthotrizine sulfone, 3,3 ', 4,4'-biphenyltetramine, 3,3 ', 4,4'-tetraaminodiphenyl ether, diaminoanthraquinone 1,5-diaminoanthraquinone, bis [4- (4-aminophenoxy) phenyl] sulfone, bis [4- (3-aminophenoxy) phenyl] sulfone, bis [4- (2-aminophenoxy) phenyl] sulfone, 3,3'-dichloro-4,4'-diaminobiphenyl, 3,3'-dihydroxy-4,4'-diaminobiphenyl, 4,4'-diaminobiphenyl, 9,9-bis (4-aminophenyl) fluorene 4,4'-dimethyl-3,3'-diaminodiphenylsulfone, 3,4'-bisaniline A, bisaniline M, bisaniline P, methylene-bis-2,6-xylidine, 4-diaminocumene, 2,5- Dichloro-p-phenylenediamine, 2,6-dichloro-p-phenylenediamine, 2,5-dimethyl-p-phenylene Amine, 2-chloro-p-phenylenediamine, 4-chloro-m-phenylenediamine, 5-chloro-2-methyl-p-phenylenediamine, acetoguanamine, 2,3,5,6-tetramethyl-p-phenylene Diamine, 2,4,6-trimethyl-m-phenylenediamine, bis-3-aminopropyl-tetramethyldisiloxane, 2,7-diaminofluorene, 2,5-diaminoviridine, p-phenylenediamine, 1,2 -Bis (anilino) ethane, diaminobenzanilide, diaminobenzoate, 1,5-diaminonaphthalene, diaminotoluene, diaminobenzotrifluoride, diaminoanthraquinone, 1,3-bis (anilino) hexafluoropropane, 1,4-bis ( Anilino) octafluorobutane, 1,5-bis Anilino) decafluoropentane, 1,7-bis (anilino) tetradecafluoroheptane, 2,2-bis [4- (3-aminophenoxy) phenyl] hexafluoropropane, 2,2-bis [4- (2 -Aminophenoxy) phenyl] hexafluoropropane, 2,2-bis [4- (4-aminophenoxy) -3,5-ditrifluoromethylphenyl] hexalfluoropropane, p-bis (4-amino-2-tri Fluoromethylphenoxy) benzene, 4,4'-bis (4-amino-2-trifluoromethylphenoxy) biphenyl, 4,4'-bis (4-amino-3-trifluoromethylphenoxy) biphenyl, 4,4 ' -Bis (4-amino-2-trifluoromethylphenoxy) diphenylsulfone, 4,4'-bis (3-amino- 5-trifluoromethylphenoxy) diphenyl sulfone, 2,2-bis [4- (4-amino-3-trifluoromethylphenoxy) phenyl] hexafluoropropane, 3,3 ′, 5,5′-tetramethylbenzidine, 3,3'-dimethoxybenzidine, o-tolidine-m-tolidine, 2,2 ', 5,5', 6,6'-hexafluorotrizine, and 4,4 '"-diaminoquaterphenyl and mixtures thereof It is.
[0044]
Particularly advantageous diamines include, but are not limited to, 1,4-benzenediamine, 6-methyl-1,3-benzenediamine, 4,4'-diamino-3,3'-dimethyl-1,1'-biphenyl, 4,4'-amino-3,3'-dimethoxy-1,1'-biphenyl, 4,4'-methylenebis (benzeneamine), 4,4'-oxybis (benzeneamine), 3,4'-oxybis ( Benzenamine), 4,4'-thiobis (benzeneamine), 4,4'-sulfonyl (benzeneamine), 3,3'-sulfonyl (benzeneamine), 1-trifluoromethyl-2,2,2-triamine Fluoroethylidine-4,4'-bis (benzeneamine), 2,2'-bis (4- (4-aminophenoxy) phenyl) sulfone, bis (4- (3-aminophenoxy) phene B) sulfone, 1,3-bis [1- (4-aminophenyl) -1-methylethylidene] benzene, 1,4-bis (3-aminophenoxy) benzene, 1,3-bis (3-aminophenoxy) Benzene and 9,9-bis (4-aminophenyl) fluorenediaminoaminosiloxane can be exemplified. These can be used alone or as a mixture of two or more to form a polyimide composition.
[0045]
In addition, the polyimide may be a block copolyimide composed of three or more components synthesized via a polyimide oligomer. If an appropriate component is used in the block copolyimide, desirable solvent solubility, electrophoresis, heat resistance, hydrophilicity, mechanical properties and the like can be satisfied at the same time.
[0046]
In order to produce a polyimide having improved mechanical strength, heat resistance, heat aging resistance and processability, an oligomer of sulfonamide is produced, and then an acid dianhydride is added to obtain a blockable polyimide resin.
[0047]
Further, in a polar solvent, 1.5 to 2.0 moles of an acid dianhydride is added to a diamine and reacted at a low temperature to synthesize an amide acid oligomer. When an equivalent amount of isocyanate is added thereto and reacted, a polyimide amide carboxylic acid is obtained while generating carbon dioxide gas.
[0048]
Also, in order to obtain a polyimide film having good substrate adhesion, an acid dianhydride is added to a diaminosiloxane copolymer to form a siloxane-amic acid block copolymer, and an equivalent amount of a diamine is added thereto to obtain a polyamic acid. The siloxane-imide block copolymer can then be prepared by heat or chemical treatment.
[0049]
Further, an acid dianhydride is added to the aromatic diamine in an excess or under amount, and the acid dianhydride is reacted to produce a polyamic acid prepolymer, and then a shortage of diamine is added to obtain a polyamic acid copolymer, The polyimide copolymer can then be produced by chemical or heat treatment, in which the two different block copolymers are combined to prevent the exchange reaction of the resulting polyamic acid, as the intermediate is via polyamic acid. Therefore, it becomes a block polymer with randomness.
[0050]
The electrodepositable polyimide can be obtained by using an acid dianhydride or a diamine into which a substituent that ionizes to give a cation or an anion is introduced. As a substituent providing a cation, for example, a trifunctional blocked isocyanate or a prepolymer of isocyanate is mixed with a polymer having a hydroxyl group or an amine group as a functional group, and then co-dispersed in a water / acid solution.
[0051]
Primary, secondary and tertiary amines, quaternary ammonium salts, quaternary ammonium hydroxides, quaternary phosphates, tertiary sulfates, quaternary which become water-soluble by the addition of acids And ammonium carboxylate. In order to obtain a cationic electrodepositable polyimide, such a substituent may be introduced into a polyimide chain. Most preferably, 2,6-diaminopyridine is used as part of the diamine component.
[0052]
The substituent providing an anion is preferably a carboxyl group. Such a substituent may be introduced into the polyimide chain in order to obtain an anionic electrodepositable polyimide. As the aromatic diamine used for the most preferable polyimide, coexistence of an aromatic diaminocarboxylic acid is required.
[0053]
Examples of the aromatic diaminocarboxylic acid include 3,5-diaminobenzoic acid, 2,4-diaminophenylacetic acid, 2,5-diaminoterephthalic acid, 3,5-diaminoparatoluic acid, and 3,5-diamino-2-naphthalene. There are carboxylic acid, 1,4-diamino-2-naphthalene carboxylic acid and the like, and 3,5-diaminobenzoic acid is particularly preferably used.
[0054]
《Light curable ink》
The materials used for preparing the photocurable ink according to the present invention will be described.
[0055]
The photocurable ink according to the present invention preferably contains an epoxy compound, an epoxidized oil, an oxetane compound, an aprotic solvent, a radical polymerizable monomer, a coloring material, and other additives as shown below as constituent components. .
[0056]
As the cationic polymerizable compound, an epoxy compound, an epoxidized oil, an oxetane compound, or the like can be used. As the radical polymerizable compound, the following radical polymerizable monomers can be used.
[0057]
《Epoxy compound》
The epoxy compound according to the present invention will be described.
[0058]
Preferred as aromatic epoxides are di- or polyglycidyl ethers prepared by reacting a polyhydric phenol having at least one aromatic nucleus or an alkylene oxide adduct thereof with epichlorohydrin, such as bisphenol A or its alkylene oxide. Examples include di- or polyglycidyl ether of an adduct, di- or polyglycidyl ether of a hydrogenated bisphenol A or an alkylene oxide adduct thereof, and a novolak-type epoxy resin. Here, examples of the alkylene oxide include ethylene oxide and propylene oxide.
[0059]
The alicyclic epoxide is obtained by epoxidizing a compound having a cycloalkane ring such as at least one cyclohexene or cyclopentene ring with a suitable oxidizing agent such as hydrogen peroxide or peracid. Compounds containing cyclohexene oxide or cyclopentene oxide are preferred.
[0060]
Preferred examples of the aliphatic epoxide include di- or polyglycidyl ether of an aliphatic polyhydric alcohol or an alkylene oxide adduct thereof, and typical examples thereof include diglycidyl ether of ethylene glycol, diglycidyl ether of propylene glycol and Diglycidyl ethers of alkylene glycols such as diglycidyl ether of 1,6-hexanediol, polyglycidyl ethers of polyhydric alcohols such as di- or triglycidyl ether of glycerin or alkylene oxide adduct thereof, polyethylene glycol or alkylene oxide adduct thereof Of polyalkylene glycols such as diglycidyl ethers of polypropylene glycol or diglycidyl ether of an alkylene oxide adduct thereof Glycidyl ether, and the like. Here, examples of the alkylene oxide include ethylene oxide and propylene oxide.
[0061]
Among these epoxides, an aromatic epoxide and an alicyclic epoxide are preferable, and an alicyclic epoxide is particularly preferable, in consideration of the rapid curing property. In the present invention, one of the above epoxides may be used alone, or two or more may be used in an appropriate combination.
[0062]
《Epoxylated oil》
Among the epoxy compounds described above, the following epoxidized oils are preferably used in the present invention.
[0063]
The epoxidized oil according to the present invention is an epoxidized oil or fat obtained by epoxidizing an oil or fat containing an unsaturated fatty acid, for example, epoxidized soybean oil, epoxidized anima oil, epoxidized castor oil, epoxidized safflower oil; Epoxidized fatty acid esters obtained by epoxidizing alkyl esters of fatty acids; didecyl-4,5-epoxytetrahydrophthalate, diisodecyl-4,5-epoxytetrahydrophthalate, didodecyl-4,5-epoxytetrahydrophthalate, 1,2-epoxycyclohexene, etc. And the like in which the cyclohexene ring of the above is epoxidized. One or more of these epoxidized oils can be used. Of these epoxidized oils, epoxidized oils and fats are preferred, and epoxidized soybean oil and epoxidized linseed oil are preferred.
[0064]
The content of the epoxy compound and the epoxidized oil according to the present invention in the ink is preferably from 10% by mass to 80% by mass, and more preferably from 10% by mass to 50% by mass.
[0065]
《Oxetane compound》
In the present invention, a conventionally known oxetane compound can be used. Examples of the oxetane compound include known oxetane compounds as disclosed in JP-A-2001-220526 and JP-A-2001-310937. .
[0066]
Examples of the oxetane compound used in the present invention include a compound represented by the following general formula (1).
[0067]
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[0068]
In the general formula (1), R¹Is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms such as a methyl group, an ethyl group, a propyl group or a butyl group, a fluoroalkyl group having 1 to 6 carbon atoms, an allyl group, an aryl group, a furyl group or a thienyl group. R²Is an alkyl group having 1 to 6 carbon atoms such as a methyl group, an ethyl group, a propyl group, a butyl group, a 1-propenyl group, a 2-propenyl group, a 2-methyl-1-propenyl group, a 2-methyl-2- Aromatic rings such as alkenyl groups having 2 to 6 carbon atoms such as propenyl group, 1-butenyl group, 2-butenyl group and 3-butenyl group, phenyl group, benzyl group, fluorobenzyl group, methoxybenzyl group, phenoxyethyl group and the like. A group having 2 to 6 carbon atoms, such as an alkylcarbonyl group having 2 to 6 carbon atoms, such as an ethylcarbonyl group, a propylcarbonyl group, or a butylcarbonyl group, an ethoxycarbonyl group, a propoxycarbonyl group, or a butoxycarbonyl group. Group, ethylcarbamoyl group, propylcarbamoyl group, butylcarbamoyl group, pentylcarbamoyl group, etc. Of 2-6 carbon atoms which is N- alkylcarbamoyl group. As the oxetane compound used in the present invention, it is particularly preferable to use a compound having one oxetane ring, since the resulting ink has excellent tackiness, low viscosity and excellent workability.
[0069]
Examples of the compound having two oxetane rings include a compound represented by the following general formula (2).
[0070]
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[0071]
In the general formula (2), R¹Is a group similar to that in the general formula (1). R³Is, for example, a linear or branched alkylene group such as an ethylene group, a propylene group or a butylene group, or a linear or branched poly (alkyleneoxy) group such as a poly (ethyleneoxy) group or a poly (propyleneoxy) group. Linear or branched unsaturated hydrocarbon groups such as propenylene group, methylpropenylene group, butenylene group, or carbonyl group or alkylene group containing carbonyl group, alkylene group containing carboxyl group, alkylene group containing carbamoyl group, etc. It is.
[0072]
Also, R³Examples thereof include polyvalent groups selected from the groups represented by the following general formulas (3), (4) and (5).
[0073]
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[0074]
In the general formula (3), R⁴Is an alkyl group having 1 to 4 carbon atoms such as a hydrogen atom, a methyl group, an ethyl group, a propyl group, or a butyl group; an alkoxy group having 1 to 4 carbon atoms such as a methoxy group, an ethoxy group, a propoxy group, or a butoxy group. , A nitro group, a cyano group, a mercapto group, a lower alkoxycarbonyl group, a carboxyl group, or a carbamoyl group.
[0075]
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[0076]
In the general formula (4), R⁵Represents an oxygen atom, a sulfur atom, a methylene group, NH, SO, SO₂, C (CF₃)₂, Or C (CH₃)₂Represents
[0077]
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[0078]
In the general formula (5), R⁶Is an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, a propyl group, and a butyl group, or an aryl group. n is an integer of 0 to 2000. R⁷Is an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, a propyl group, and a butyl group, or an aryl group. R⁷Examples further include groups selected from groups represented by the following general formula (6).
[0079]
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[0080]
In the general formula (6), R⁸Is an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, a propyl group, and a butyl group, or an aryl group. m is an integer of 0 to 100.
[0081]
Specific examples of the compound having two oxetane rings include the following compounds.
[0082]
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[0083]
Exemplified compound 1 is a compound represented by the general formula (2)¹Is an ethyl group, R³Is a carboxyl group. In addition, Exemplified Compound 2 is a compound represented by the general formula (2)¹Is an ethyl group, R³Is R in the general formula (5).⁶And R⁷Is a methyl group and n is 1.
[0084]
Among the compounds having two oxetane rings, preferred examples other than the above compounds include compounds represented by the following general formula (7). In the general formula (7), R¹Is the R of the above general formula (1)¹Is synonymous with
[0085]
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[0086]
In addition, as an example of the compound having 3 to 4 oxetane rings, a compound represented by the following general formula (8) can be given.
[0087]
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[0088]
In the general formula (8), R¹Is R in the general formula (1).¹Is synonymous with R⁹Examples thereof include a branched alkylene group having 1 to 12 carbon atoms such as a group represented by the following A to C, a branched poly (alkyleneoxy) group such as a group represented by the following D, or the following E: And a branched polysiloxy group such as a group. j is 3 or 4.
[0089]
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[0090]
In the above A, R¹⁰Is a lower alkyl group such as a methyl group, an ethyl group or a propyl group. In the above D, p is an integer of 1 to 10.
[0091]
As an example of the compound having 3 to 4 oxetane rings, Exemplified Compound 3 is given.
[0092]
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[0093]
Further, examples of the compound having 1 to 4 oxetane rings other than those described above include a compound represented by the following general formula (9).
[0094]
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[0095]
In the general formula (9), R⁸Is the R of the general formula (19)⁸Is synonymous with R¹¹Is an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, a propyl group or a butyl group or a trialkylsilyl group, and r is 1 to 4.
[0096]
Preferred specific examples of the oxetane compound according to the present invention include the following compounds.
[0097]
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[0098]
The method for producing each compound having an oxetane ring described above is not particularly limited, and may be in accordance with a conventionally known method. For example, Pattisson (DB Pattison, J. Am. Chem. Soc., 3455, 79) (1957)) discloses an oxetane ring synthesis method from a diol. In addition to these, compounds having 1 to 4 oxetane rings having a high molecular weight of about 1,000 to 5,000 are also exemplified. Specific examples of these compounds include the following compounds.
[0099]
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[0100]
《Aprotic polar solvent》
The aprotic polar solvent used in the present invention will be described.
[0101]
Examples of the aprotic polar solvent include dimethylimidazolidinone, N-methylpyrrolidone (NMP), N, N-dimethylformamide (DMF), N, N-dimethylacetamide (DMAc), dimethylsulfoxide (DMSO), sulfolane, , 4-Dimethylsulfolane, sulfolene, quinoline, isoquinoline, 2,6-lutidine, 2,4,6-trimethylpyridine, tetramethylurea, dioxane, tetrahydrofuran (THF), hexamethylphosphoric triamide (HMPA), N- Examples thereof include methylmorpholine (NMm), γ-butyrolactone (BLo), nitromethane, and a compound having a nitrile group.
[0102]
Among them, the above-mentioned compounds having a nitrile group are particularly preferably used. Examples of the compound having a nitrile group include acetonitrile (AcN), butyronitrile, acrylonitrile, and the like.
[0103]
(Amount of aprotic polar solvent used)
The amount of the aprotic polar solvent used is in the range of 0 parts by mass to 20 parts by mass with respect to 100 parts by mass of the total amount of the ink from the viewpoint of preferably exhibiting the effects described in the present invention and preventing color turbidity and the like. Is preferably 0 parts by mass to 10 parts by mass, and particularly preferably 0 parts by mass to 5 parts by mass.
[0104]
《Radical polymerizable monomer》
Various (meth) acrylate monomers can be used as the radical polymerizable monomer according to the present invention. For example, isoamyl acrylate, stearyl acrylate, lauryl acrylate, octyl acrylate, decyl acrylate, isomyristyl acrylate, isostearyl acrylate, 2-ethylhexyl-diglycol acrylate, 2-hydroxybutyl acrylate, 2-acryloyloxyethyl hexahydrophthalic acid Butoxyethyl acrylate, ethoxydiethylene glycol acrylate, methoxydiethylene glycol acrylate, methoxypolyethylene glycol acrylate, methoxypropylene glycol acrylate, phenoxyethyl acrylate, tetrahydrofurfuryl acrylate, isobornyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, Hydroxy-3-phenoxypropyl acrylate, 2-acryloyloxyethyl succinic acid, 2-acryloyloxyethyl phthalic acid, 2-acryloyloxyethyl-2-hydroxyethyl-phthalic acid, lactone-modified flexible acrylate, t- Monofunctional monomers such as butylcyclohexyl acrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, tripropylene glycol diacrylate, polypropylene glycol diacrylate, 1,4-butanediol diacrylate, 1,6- Hexanediol diacrylate, 1,9-nonanediol diacrylate, neopentyl glycol diacrylate, dimethylol-tricyclodecane diacrylate, bis EO adduct diacrylate of enol A, PO adduct diacrylate of bisphenol A, bifunctional monomers such as neopentyl glycol diacrylate hydroxypivalate, polytetramethylene glycol diacrylate, trimethylolpropane triacrylate, EO-modified trimethylolpropane Triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, ditrimethylolpropane tetraacrylate, glycerin propoxy triacrylate, cowprolactone modified trimethylolpropane triacrylate, pentaerythritol ethoxy tetraacrylate, caprolactam modified dipenta Three officials such as erythritol hexaacrylate Or higher functional monomers.
[0105]
In order to suppress the curing shrinkage of the ink surface when light (also referred to as actinic ray) is irradiated, it is preferable to use a monomer having a curing shrinkage of 10% or less. Above all, monofunctional monomers are preferably used because they have a low shrinkage ratio as compared with difunctional or higher functional monomers, and also provide flexibility to the ink image, curling can be suppressed, and adhesion to the recording material can be obtained. it can.
[0106]
The content of the radical polymerizable monomer according to the present invention in the ink is preferably in the range of 10% by mass to 50% by mass, and more preferably in the range of 10% by mass to 30% by mass.
[0107]
《Photoacid generator》
The photoacid generator used in the present invention will be described.
[0108]
As the photoacid generator, for example, a chemical amplification type photoresist or a compound used for photocation polymerization is used (Organic Materials Research Group, "Organic Materials for Imaging", Bunshin Publishing (1993)). -See pages 187-192, Technical Information Association-"Photocuring Technology"-Photoacid generator introduced in 2001). Examples of compounds suitable for the present invention are given below. First, B (C) of an aromatic onium compound such as diazonium, ammonium, iodonium, sulfonium, and phosphonium is used.₆F₅)₄ ⁻, PF₆ ⁻, AsF₆ ⁻, SbF₆ ⁻, CF₃SO₃ ⁻Salts may be mentioned. Those having a borate compound as a counter anion are preferable because of high acid generating ability. Specific examples of the onium compound are shown below.
[0109]
Second, a sulfonated compound that generates sulfonic acid can be given. Specific compounds are exemplified below. Third, halides that photogenerate hydrogen halides can also be used. Fourth, an iron allene complex can be mentioned.
[0110]
The compound examples are shown below, but the present invention is not limited thereto.
[0111]
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[0112]
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[0113]
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[0114]
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[0115]
《Photo radical generator》
Examples of the photogenerating agent used in the present invention include arylalkyl ketone, oxime ketone, acylphosphine oxide, acylphosphonate, S-phenyl thiobenzoate, titanocene, aromatic ketone, thioxanthone, benzyl and quinone derivatives or ketocoumarins. Conventionally known ones can be used.
[0116]
Among them, acylphosphine oxide and acylphosphonate are particularly effective for internal curing in an ink image having a thickness of 5 μm to 15 μm per color such as an ink jet method because the sensitivity is high and the absorption is reduced by photocleavage of the initiator. It is.
[0117]
Specifically, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, bis (2,6-dimethoxybenzoyl) -2,4,4-trimethyl-pentylphosphine oxide and the like are preferable.
[0118]
In addition, in consideration of high sensitivity, safety and odor, 1-hydroxy-cyclohexyl-phenyl-ketone, 2-methyl-1 [4- (methylthio) phenyl] -2-morpholinopropan-1-one, 2-hydroxy-2-methyl-1-phenyl-propan-1-one and 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1 are preferably used.
[0119]
In the combination considering oxygen polymerization inhibition and sensitivity, a combination of 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1 and 1-hydroxy-cyclohexyl-phenyl-ketone, 1-hydroxy- Combination of cyclohexyl-phenyl-ketone and benzophenone, 2-methyl-1 [4- (methylthio) phenyl] -2-morpholinopropan-1-one or 2-methyl-1 [4- (methylthio) phenyl]- A combination of 2-morpholinopropan-1-one with diethylthioxanthone or isopropylthioxanthone, a combination of benzophenone with an acrylic acid derivative having a tertiary amino group, and the addition of a tertiary amine are effective.
[0120]
《Color material》
When coloring the ink composition according to the present invention, a coloring material is added. As the coloring material, various coloring materials that can be dissolved or dispersed in the main component of the polymerizable compound can be used, and a pigment is preferable from the viewpoint of weather resistance.
[0121]
Pigments that can be preferably used in the present invention are listed below.
C. I Pigment Yellow-1, 3, 12, 13, 14, 17, 81, 83, 87, 95, 109, 42,
C. I Pigment Orange-16, 36, 38,
C. I Pigment Red-5, 22, 38, 48: 1, 48: 2, 48: 4, 49: 1, 53: 1, 57: 1, 63: 1, 144, 146, 185, 101,
C. I Pigment Violet-19, 23,
C. I Pigment Blue-15: 1, 15: 3, 15: 4, 18, 60, 27, 29,
C. I Pigment Green-7, 36,
C. I Pigment White-6, 18, 21,
C. I Pigment Black-7,
Further, in the present invention, it is preferable to use a white ink in order to enhance the color concealing property on a transparent substrate such as a plastic film. In particular, in soft packaging printing and label printing, it is preferable to use white ink, but since the ejection amount increases, the ejection stability described above, from the viewpoint of the occurrence of curling and wrinkling of the recording material, the use amount is naturally determined. There is a limit.
[0122]
For dispersion of the pigment, for example, a ball mill, a sand mill, an attritor, a roll mill, an agitator, a Henschel mixer, a colloid mill, an ultrasonic homogenizer, a pearl mill, a wet jet mill, a paint shaker, and the like can be used. In dispersing the pigment, a dispersant may be added. As the dispersant, a polymer dispersant is preferably used, and as the polymer dispersant, Solsperse series of Avecia is mentioned. In addition, as a dispersing aid, a synergist corresponding to various pigments can be used. These dispersants and dispersing aids are preferably added in an amount of 1 part by mass to 50 parts by mass based on 100 parts by mass of the pigment. The dispersing medium is performed using a solvent or a polymerizable compound. However, in the case of the radiation-curable ink used in the present invention, it is preferable to use no solvent in order to react and cure immediately after the ink lands. If the solvent remains in the cured image, problems such as deterioration of the solvent resistance and VOC of the remaining solvent occur. Therefore, it is preferable from the viewpoint of dispersibility that the dispersion medium is not a solvent but a polymerizable compound, and among them, a monomer having the lowest viscosity is selected.
[0123]
The pigment is dispersed preferably such that the average particle size of the pigment particles is 0.08 μm to 0.5 μm, and the maximum particle size is 0.3 μm to 10 μm, preferably 0.3 μm to 3 μm. The selection of the dispersion medium, dispersion conditions, and filtration conditions are appropriately set. By controlling the particle size, clogging of the head nozzle can be suppressed, and the storage stability of the ink, the transparency of the ink, and the curing sensitivity can be maintained.
[0124]
In the ink according to the present invention, the colorant concentration is preferably 1% by mass to 10% by mass of the whole ink.
[0125]
《Additives etc.》
Various additives other than those described above can be used in the ink according to the present invention. For example, in order to enhance the storage stability of the ink composition, a polymerization inhibitor can be added in an amount of 200 ppm to 20,000 ppm. Since it is preferable that the ultraviolet curable ink is heated and reduced in viscosity before ejection, it is preferable to add a polymerization inhibitor in order to prevent head clogging due to thermal polymerization. In addition, if necessary, surfactants, leveling additives, matting agents, polyester resins for adjusting film properties, polyurethane resins, vinyl resins, acrylic resins, rubber resins, waxes, etc. Can be added. It is also effective to add a trace amount of an organic solvent in order to improve the adhesion to the recording medium. In this case, the addition is effective within a range in which the problem of solvent resistance and VOC does not occur, and the amount used is in the range of 0.1% to 5%, preferably 0.1% to 3%.
[0126]
As these various monomers and coloring materials, those disclosed in World Patent No. 99/29787 and JP-A-2001-220526 can be used. In addition, these references can be referred to for initiators, additives, and the like.
[0127]
As the photocurable ink according to the present invention, a cationically polymerizable ink and a radically polymerizable ink can be used alone, but they can also be mixed and used as a hybrid ink. .
[0128]
The ink jet head of the present invention is suitable for these cationically polymerizable or radically polymerizable inks, but can exhibit excellent durability especially when using a cationically polymerizable ink.
[0129]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited thereto.
[0130]
FIG. 1 is a schematic cross-sectional view of an inkjet ink supply pump according to an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a substrate on which a cylindrical chamber 2 is formed. The inner peripheral surface 2a of the cylindrical chamber 2 is circular and is formed in a range larger than a semicircle and smaller than the entire circumference, and the inner peripheral surface 2a is formed. Portions that are not covered are openings 2b. Reference numeral 3 denotes a tube made of an elastic material, which is arranged in a ring shape along the inner peripheral surface 2a of the cylindrical chamber 2 and whose both ends are drawn out of the substrate 1 to form an inlet 3a and an outlet 3b. I have. The substrate 1 is made of, for example, a molded product of a rubber-based material such as NBR or a synthetic resin such as ABS, and the tube 3 according to the present invention is used as the tube 3.
[0131]
Reference numeral 4 denotes a ring-shaped pressing member disposed inside the tube 3, which has a double structure of an inner ring 41 and an outer ring 42. The inner ring 41 of the pressing member 4 is a rigid body having a small friction coefficient. The outer ring 42 is made of a material, for example, a fluororesin synthetic resin molded product, and the outer ring 42 is made of an elastic material having a large friction coefficient such as rubber. As shown in FIG. 2, the inner ring 41 and the outer ring 42 have a rectangular cross section and are formed with dimensions so as to overlap with each other, and the ridge 41 c provided on the outer peripheral surface 41 b of the inner ring 41 is The outer ring 42 is held by the inner ring 41 in a freely rotatable state by being fitted into a circumferential groove 42c provided on the surface 42a. Conversely, a ridge may be provided on the outer ring 42 and a circumferential groove may be provided on the inner ring 41, or the ridge and the circumferential groove may be formed into a groove type.
[0132]
Reference numeral 5 denotes an eccentric rotor disposed inside the pressing member 4, and reference numeral 6 denotes a rotating shaft to which the eccentric rotor 5 is attached, and the tip 5 a of the eccentric rotor 5 slides on the inner peripheral surface 41 a of the inner ring 41. The pressure member 4 is configured to rotate and press the pressure member 4 toward the inner peripheral surface 2a of the cylindrical chamber 2 so that the pressure member 4 moves circularly along the inner peripheral surface 2a. A motor with a speed reducer for driving the rotary shaft 6 and the like are disposed on the back side of the substrate 1 and a cover is provided on the front side, but these are not shown.
[0133]
The radius of the outer peripheral surface 42b of the outer ring 42 of the pressure member 4 is selected to be a dimension obtained by subtracting at least twice the thickness of the tube 3 from the radius of the cylindrical chamber 2. The sum of the distance from the axis of the rotating shaft 6 to the tip 5a of the eccentric rotor 5 and the dimension from the inner peripheral surface 41a of the inner ring 41 to the outer peripheral surface 42b of the outer ring 42 is added by the tip 5a of the eccentric rotor 5. When the pressure member 4 is pushed toward the inner peripheral surface 2 a of the substrate 1, the tube 3 is crushed by the outer ring 42 and the internal flow path is completely closed.
[0134]
Since the illustrated example is configured as described above, when the eccentric rotor 5 is rotated clockwise as shown by the arrow to cause the pressing member 4 to make a circular motion, the tube 3 generated by being pressed by the pressing member 4 The closed position also moves clockwise, and the fluid inside the tube is discharged from the outlet 3b and simultaneously sucked in from the inlet 3a to perform a pump action.
[0135]
FIG. 3 is a schematic cross-sectional view of another ink-jet ink supply pump according to the embodiment of the present invention. 1 and 2 are denoted by the same reference numerals.
[0136]
In FIG. 3, reference numeral 15 denotes a supporting means provided as the above-described rotation stopping mechanism, which is formed by a combination of a support shaft 16 fixed to the substrate 1 and a hole 17 formed in the inner ring 41 of the pressing member 4. The ring 41 is supported in the cylindrical chamber 2, and in this example, the support means 15 is provided at two upper and lower positions on a vertical center line in the illustrated posture. The diameter of the support shaft 16 is selected so as to obtain a required strength, and the hole 17 is a round hole. The diameter of the support shaft 16 is such that the pressurizing member 4 has a degree of freedom of movement enough to exert a pressing action on the tube 3 without hindrance. Has been selected. 4, the support shaft 16 may be provided in the inner ring 41 and the hole 17 may be provided in the substrate 1. The hole 17 does not necessarily have to be a round hole, and any appropriate shape other than a circle can be adopted as long as the shape and size ensure the degree of freedom of movement of the pressing member 4.
[0137]
When the eccentric rotor 5 is rotated in such a configuration, the inner ring 41 can be continuously rotated in the same direction because the inner ring 41 is prevented from rotating by the support means 15 including the combination of the support shaft 16 and the hole 17. When the eccentric rotor 5 is downward, the pendulum motion mainly using the upper support means 15 as a fulcrum is added to the circular motion. When the eccentric rotor 5 is upward, pendulum motion mainly using the lower support means 15 as a fulcrum. Is added to the circular motion, but only the circular motion for sequentially pressing the tube 3 is performed while maintaining the substantially same posture as a whole. Accordingly, as described above, the slip between the inner ring 41 and the outer ring 42 does not occur, and the inner ring 41 itself does not continuously rotate in the same direction, so that the rotational force applied to the outer ring 42 becomes extremely small. Therefore, the phenomenon in which the tube 3 is pulled hardly occurs.
[0138]
When such a supporting means 15 is provided, when the eccentric rotor 5 moves from the outflow port 3b to the inflow port 3a, the pendulum motion of the pressing member 4 with the lower supporting means 15 as a fulcrum is required. Occurs. For this reason, in the case of the conventional example in which the entire pressure member 4 is integrally formed and the outer ring 42 is not provided, a portion near the outlet 3b of the tube 3 pressed by the pressure member 4 is: With the movement of the outer peripheral surface of the pressure member 4 due to the pendulum movement, a phenomenon of being dragged toward the inflow port 3a tends to occur, and a part of the tube 3 projects to the opening 2b to generate a waist break portion 3c. Often it causes damage and reduced flow rate.
[0139]
This phenomenon is likely to occur even if the space between the pressing member 4 and the tube 3 is sufficiently lubricated. However, as shown in this embodiment, the outer ring 42 which is slidable relative to the inner ring 41 is provided on the pressing member 4. In this case, even if the outer peripheral surface 42b of the outer ring 42 that is in contact with the tube 3 attempts to move toward the inflow port 3a together with the tube 3 due to the pendulum movement, a slip occurs between the two rings 41 and 42 before that. The outer peripheral surface 42b does not move. That is, the drag phenomenon by the outer ring 42 is absorbed by the slip between the two rings 41 and 42, and the waist break portion 3c is not generated. At this portion, the tube is damaged or the flow rate is reduced. There is no problem.
[0140]
For comparison, FIG. 4 shows a schematic cross-sectional view of an existing tube liquid feeding pump.
[0141]
【Example】
Hereinafter, the present invention will be described specifically with reference to examples, but embodiments of the present invention are not limited thereto.
[0142]
Example 1
<< Preparation of ink supply pump for inkjet >>
Using the constituent members shown in Table 1, the ink supply pumps 1 for ink-jet (FIG. 1: present invention) and 2 (FIG. 3: book) having the forms shown in FIGS. Invention) and an ink supply pump 3 for ink jet (FIG. 4: Comparative Example) were produced.
[0143]
<< Preparation of ink delivery tube for inkjet >>
Using the polypropylene obtained by using calcium carbonate or magnesium carbonate shown in Table 1 as a neutralizing agent of the catalyst at the time of polymerization, an ink jet tube for ink jet of the present invention was prepared. A comparative example ink jet ink delivery tube was prepared in the same manner as in the present invention except that calcium stearate was used as the neutralizing agent of the catalyst during the polymerization.
[0144]
<< Preparation of inkjet ink >>
A magenta pigment dispersion was prepared as described below, and then a magenta ink (also used as an immersion liquid in an ink immersion test) was prepared using the obtained magenta pigment dispersion.
[0145]
(A) Preparation of magenta pigment dispersion
A magenta pigment dispersion was obtained with the following composition.
[0146]

Using the magenta pigment dispersion obtained above, the following formulation was performed, followed by filtration through a 0.8 μm membrane filter, and dehydration under reduced pressure while heating to 50 ° C. to obtain a magenta ink.
[0147]
(Composition of magenta ink)
Magenta pigment dispersion 17 parts by mass
Aron Oxetane OXT-221 (Toa Gosei) 70 parts by mass
Celloxide 2021P (DAIcel UCB) 30 parts by mass
UVI-6990 (manufactured by Dow Chemical, photoacid generator) 5 parts by mass
<< Evaluation of ink immersion in ink supply tube >>
Using the above magenta ink as an immersion liquid, the above-described ink immersion test was performed on each of the obtained ink transfer tubes to determine the mass change rate (%) and the ink turbidity change rate of the ink transfer tube. Was. The results obtained are shown in Table 2.
[0148]
<< Continuous emission test using inkjet printer >>
The inkjet head was connected and a continuous emission test was performed as follows.
[0149]
The above-prepared ink feeding pump and ink feeding tube were respectively mounted on an ink jet printer (Olympus PJ5400), and the magenta ink (also used for the ink immersion test) was maintained at an ink temperature of 50 ° C. A continuous printing test was performed to evaluate ink ejection accuracy and ink jet head nozzle clogging.
[0150]
Table 2 shows the obtained results.
[0151]
[Table 1]

[0152]
[Table 2]

[0153]
As can be seen from the above table, the mass change rate (%) and the ink turbidity change rate of the ink feeding tube are improved by the configuration of the present invention, as compared with the comparative example. It turns out that it shows.
[0154]
Example 2
The same evaluation as in Example 1 was performed except that the ink ejection amount was changed as shown in Table 3. Table 4 shows the results.
[0155]
[Table 3]

[0156]
[Table 4]

[0157]
From the above table, it was found that Example 1 was reproduced and good results were obtained by setting the ink discharge amount according to the present invention.
[0158]
【The invention's effect】
ADVANTAGE OF THE INVENTION By this invention, the corrosion resistance with respect to a photocurable ink is improved, ink clogging and ink leakage do not occur even if it is used for a long time, ink drop ejection accuracy can be secured stably, and the influence on ink sensitivity can be reduced. A simple recording instrument can be provided.
[Brief description of the drawings]
FIG. 1 is a schematic cross-sectional view of an inkjet ink supply pump according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view of the pressing member.
FIG. 3 is a schematic cross-sectional view of another inkjet ink supply pump according to the embodiment of the present invention.
FIG. 4 is a schematic cross-sectional view of an existing liquid feed pump of a comparative example.
[Explanation of symbols]
1 substrate
2 cylindrical chamber
2a Inner peripheral surface
3 tubes
4 Pressing member
5 Eccentric rotor
15 Supporting means (rotation stop mechanism)
16 spindle
17 holes
41 Inner ring
42 Outer ring
51 Tube receiver
52 rollers
53 rotor
54 shaft

Claims (5)

In an ink-feeding member for ink-jet using a photo-curable ink, a tube pump is used to feed the ink from the ink storage unit to the ink-jet head, and a tube pump for crushing the tube when the photo-curable ink is fed. member and the contact area a (cm ²⁾ of the tube and the tube tract area B (cm ²⁾ ratio of a / B is 10 or more, the inkjet ink feeding member, wherein 150 or less. In an ink-feeding member for ink-jet using a photo-curable ink, a tube pump is used to feed the ink from the ink storage unit to the ink-jet head, and a tube pump for crushing the tube when the photo-curable ink is fed. A ratio A / C of a contact area A (cm ² ) between the pressure member and the tube to an ink discharge amount C (ml / min) is 0.1 or more and 20 or less, wherein Element. In an ink-feeding member for ink-jet using a photocurable ink, a mass change rate of a liquid-feeding tube for feeding the ink from an ink storage unit to an ink-jet head by a UV ink immersion test is less than 50%. The ink-feeding member for inkjet according to claim 1. An ink-jet recording method using the ink-feeding member for ink-jet according to claim 1. The ink jet recording method according to claim 4, wherein a cationically polymerizable ink is used as the photocurable ink.

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