JP4168477B2 - Ink composition that realizes an image with excellent light resistance - Google Patents

Description

ベンゾトリアゾール骨格：
【００５５】
【化２】

ヒンダードフェノール骨格：
【００５６】
【化３】

サリチレート骨格：
【００５７】
【化４】

シアノアクリレート骨格：
【００５８】
【化５】

および、ヒンダードアミン骨格：
【００５９】
【化６】

である。
【００６０】
紫外線吸収能および／または光安定化能を有する部位のポリマー構造中への導入は、上記骨格を分子構造中に有する共重合可能なモノマーと他のモノマーとを共重合させることによって実施することができる。
【００６１】
本発明において、紫外線吸収能および／または光安定化能を有する部位を有するモノマーの具体例は、上記した紫外線吸収能および／または光安定化能を有する部位と、メタクロイル基、アクロイル基、ビニル基、アリル基等のエチレン性不飽和基とを有するものである。
【００６２】
そのようなモノマーの具体例としては、次のものが挙げられる。まず、ベンゾフェノン骨格を有する紫外線吸収部位を有するモノマーの具体例としては、次のものが挙げられる。
【００６３】
【化７】

【００６４】
【化８】

また、ベンゾトリアゾール骨格を有する紫外線吸収部位を有するモノマーの具体例としては、次のものが挙げられる。
【００６５】
【化９】

【００６６】
【化１０】

【００６７】
【化１１】

さらに、ヒンダードフェノール骨格を有する紫外線吸収部位を有するモノマーの具体例としては、次のものが挙げられる。
【００６８】
【化１２】

また、ヒンダードアミン骨格を有する光安定部位を有するモノマーの具体例としては、次のものが挙げられる。
【００６９】
【化１３】

【００７０】
【化１４】

紫外線吸収能および／または光安定化能を有する部位を有するモノマーとして、市販されているものを利用することも可能であり、市販品の例としては、ベンゾトリアゾール骨格を有する紫外線吸収部位を有するモノマーとして、大塚化学株式会社から入手可能なＲＵＶＡ−９３（２−（２’−ヒドロキシ−５−メチルアクリルオキシエチルフェニル）−２Ｈ−ベンゾトリアゾール）が挙げられる。また、ヒンダートアミン骨格を有する光安定化部位を有するモノマーとして、旭電化工業株式会社から入手可能なアデカスタブＬＡ−８２（１，２，２，６，６−ペンタメチル−４−ピペリジルメタクリレート）、同ＬＡ−８７（２，２，６，６−テトラメチル−４−ピペリジルメタクリレート）が挙げられる。
【００７１】
この第二の態様によるポリマー微粒子は、紫外線吸収能および／または光安定化能を有する部位を有するモノマーと、他のモノマーの種類を勘案して適宜選択される重合方法によって重合し、製造することができる。
【００７２】
本発明の好ましい態様によれば、本発明において用いられる第二の態様のポリマー微粒子は、公知の乳化重合によって得ることができる。具体的には、ポリマーを構成するモノマー成分と、紫外線吸収能および／または光安定化能を有する部位を有するモノマーとを、重合触媒、および乳化剤を存在させた水中において乳化重合することによって得ることができる。
【００７３】
この第二の態様において用いることができるポリマーを構成するモノマー成分の具体例としては、上記第一の態様のポリマー微粒子を構成するモノマー成分と同様のものが挙げられる。また、上記の乳化重合において用いられる乳化剤の具体例についても、上記第一の態様において説明したものと同様のものが挙げられる。
【００７４】
また、この第二の態様のポリマー微粒子も、ポリマーエマルジョンの形態とされてよく、上記の乳化重合により好ましく製造することができる。また、ポリマーエマルジョンの形態とされた第二の態様のポリマー微粒子として、市販品を利用することも可能であり、その例としてはＢＡＳＦ社製のＵＶＡ−３８３ＭＡおよびＵＶＡ−３８３ＭＧが挙げられる。
【００７５】
上記したように、ポリマー微粒子は、単粒子構造またはコアシェル構造とすることができ、この第二の態様のポリマー微粒子にあってもいずれの構造を採用することが可能である。
【００７６】
ここで、コアシェル構造を有する第二の態様のポリマー微粒子は、上記第一の態様において説明したような手法によって同様に製造することができる。
【００７７】
また、ポリマー微粒子がコアシェル構造である場合、紫外線吸収能および／または光安定化能を有するポリマーは、コア部とシェル層のいずれを構成するものとされてもよく、また両方を構成してもよい。
【００７８】
また、第一の態様によるポリマー微粒子と同様に、この第二の態様によるポリマー微粒子にあっても、カルボキシル基またはスルホン酸基のいずれかの官能基を有するものであるのが好ましく、さらにアミド基、水酸基、またはアミノ基を有してなるものが好ましい。また、この第二の態様によるポリマー微粒子がコアシェル構造の場合、シェル層にこれらの官能基が存在するのが好ましい。
【００７９】
３．色材
本発明によるインク組成物に含まれる色材は、染料、顔料のいずれであってもよいが、顔料が好ましい。
【００８０】
染料としては、直接染料、酸性染料、食用染料、塩基性染料、反応性染料、分散染料、建染染料、可溶性建染染料、反応分散染料、など各種染料を使用することができる。
【００８１】
また、顔料としては、無機顔料、有機顔料を使用することができる。無機顔料としては、酸化チタンおよび酸化鉄に加え、コンタクト法、ファーネス法、サーマル法などの公知の方法によって製造されたカーボンブラックを使用することができる。また、有機顔料としては、アゾ顔料（アゾレーキ、不溶性アゾ顔料、縮合アゾ顔料、キレートアゾ顔料などを含む）、多環式顔料（例えば、フタロシアニン顔料、ペリレン顔料、ペリノン顔料、アントラキノン顔料、キナクリドン顔料、ジオキサジン顔料、チオインジゴ顔料、イソインドリノン顔料、キノフラロン顔料など）、染料キレート（例えば、塩基性染料型キレート、酸性染料型キレートなど）、ニトロ顔料、ニトロソ顔料、アニリンブラックなどを使用できる。
特に黒インクとして使用されるカーボンブラックとしては、三菱化学製のNo.2300,No.900,MCF88,No.33,No.40,No.45,No.52,MA7,MA8,MA100,No2200B 等が、コロンビア社製の Raven5750,Raven5250,Raven5000,Raven3500,Raven1255,Raven700 等が、キャボット社製のRegal 400R,Regal 330R,Rega l660R,Mogul L,Monarch 700, Monarch 800, Monarch 880, Monarch 900, Monarch 1000, Monarch 1100, Monarch 1300, Monarch 1400 等が、デグッサ社製の Color Black FW1,Color Black FW2, Color Black FW2V, Color Black FW18, Color Black FW200, Color Black S150, Color Black S160, Color Black S170, Printex 35, Printex U, Printex V, Printex 140U, Special Black 6, Special Black 5, Special Black 4A, Special Black 4 等が使用できる。イエローインクに使用される顔料としては、 C.I.Pigment Yellow 1, C.I.Pigment Yellow 2, C.I.Pigment Yellow 3, C.I.Pigment Yellow 12, C.I.Pigment Yellow 13, C.I.Pigment Yellow 14C, C.I.Pigment Yellow 16 ,C.I.Pigment Yellow 17, C.I.Pigment Yellow 73, C.I.Pigment Yellow 74, C.I.Pigment Yellow 75, C.I.Pigment Yellow 83, C.I.Pigment Yellow 93, C.I.Pigment Yellow95, C.I.Pigment Yellow97, C.I.Pigment Yellow 98, C.I.Pigment Yellow114, C.I.Pigment Yellow128, C.I.Pigment Yellow129, C.I.Pigment Yellow151, C.I.Pigment Yellow154 等が挙げられる。また、マゼンタインクに使用される顔料としては、C.I.Pigment Red 5, C.I.Pigment Red 7, C.I.Pigment Red 12, C.I.Pigment Red 48(Ca), C.I.Pigment Red 48(Mn), C.I.Pigment Red 57(Ca), C.I.Pigment Red 57:1, C.I.Pigment Red 112, C.I.Pigment Red 123, C.I.Pigment Red 168, C.I.Pigment Red 184, C.I.Pigment Red 202 等が挙げられる。シアンインクに使用される顔料としては、C.I.Pigment Blue 1, C.I.Pigment Blue 2, C.I.Pigment Blue 3, C.I.Pigment Blue 15:3, C.I.Pigment Blue 15:34, C.I.Pigment Blue 16, C.I.Pigment Blue 22, C.I.Pigment Blue 60, C.I.Vat Blue 4 , C.I.Vat Blue 60 等が挙げられる。ただし、これらに限定されるものではない。
【００８２】
これらの顔料の粒径は、１０μm以下が好ましく、さらに好ましくは０．１μm以下である。
【００８３】
本発明の好ましい態様によれば、これらの顔料は、分散剤または界面活性剤で水性媒体中に分散させて得られた顔料分散液としてインクに添加されるのが好ましい。好ましい分散剤としては、顔料分散液を調製するのに慣用されている分散剤、例えば高分子分散剤を使用することができる。なお、この顔料分散液に含まれる分散剤および界面活性剤がインク組成物の分散剤および界面活性剤としても機能するであろうことは当業者に明らかであろう。高分子分散剤の好ましい例としては天然高分子が挙げられ、その具体例としては、にかわ、ゼラチン、ガゼイン、アルブミンなどのタンパク質類、アラビアゴム、トラガントゴムなどの天然ゴム類、サボニンなどのグルコシド類、アルギン酸およびアルギン酸プロピレングリコールエステルアルギン酸トリエタノールアミン、アルギン酸アンモニウムなどのアルギン酸誘導体、メチルセルロース、カルボキシメチルセルロース、ヒドロキシエチルセルロース、エチルヒドロキシセルロースなどのセルロース誘導体などが挙げられる。さらに、高分子分散剤の好ましい例として合成高分子が挙げられ、ポリビニルアルコール類、ポリビニルピロリドン類、ポリアクリル酸、アクリル酸−アクリルニトリル共重合体、アクリル酸カリウム−アクリルニトリル共重合体、酢酸ビニル−アクリル酸エステル共重合体、アクリル酸−アクリル酸エステル共重合体などのアクリル系樹脂、スチレン−アクリル酸共重合体、スチレン−メタクリル酸共重合体、スチレン−メタクリル酸−アクリル酸エステル共重合体、スチレン−α−メチルスチレン−アクリル酸共重合体、スチレン−α−メチルスチレン−アクリル酸−アクリル酸エステル共重合体などのスチレン−アクリル樹脂、スチレン−マレイン酸共重合体、スチレン−無水マレイン酸共重合体、ビニルナフタレン−アクリル酸共重合体、ビニルナフタレン−マレイン酸共重合体、および酢酸ビニル−エチレン共重合体、酢酸ビニル−脂肪酸ビニルエチレン共重合体、酢酸ビニル−マレイン酸エステル共重合体、酢酸ビニル−クロトン酸共重合体、酢酸ビニル−アクリル酸共重合体などの酢酸ビニル系共重合体およびそれらの塩が挙げられる。これらの中で、特に疎水性基を持つモノマーと親水性基を持つモノマーとの共重合体、および疎水性基と親水性基を分子構造中に併せ持ったモノマーからなる重合体が好ましい。
【００８４】
本発明のインク組成物における顔料の含有量は、０．５〜２５重量％程度が好ましく、より好ましくは２〜１５重量％程度である。
【００８５】
４．水溶性有機溶剤
また、本発明によるインク組成物は水溶性有機溶媒を含んでなる。この水溶性有機溶媒は、好ましくは低沸点有機溶剤であり、その例としては、メタノール、エタノール、ｎ−プロピルアルコール、ｉｓｏ−プロピルアルコール、ｎ−ブタノール、ｓｅｃ−ブタノール、ｔｅｒｔ−ブタノール、ｉｓｏ−ブタノール、ｎ−ペンタノールなどがあげられる。特に一価アルコールが好ましい。低沸点有機溶剤は、インクの乾燥時間を短くする効果がある。低沸点有機溶剤の添加量はインクの０．１〜３０重量％が好ましく、より好ましくは５〜１０重量％の範囲である。
【００８６】
また、本発明の好ましい態様によれば、本発明に使用するインク組成物は、さらに高沸点有機溶媒からなる湿潤剤を含んでなることが好ましい。高沸点有機溶媒剤の好ましい例としては、エチレングリコール、ジエチレングリコール、トリエチレングリコール、ポリエチレングリコール、ポリプロピレングリコール、プロピレングリコール、ブチレングリコール、１，２，６−ヘキサントリオール、チオグリコール、ヘキシレングリコール、グリセリン、トリメチロールエタン、トリメチロールプロパンなどの多価アルコール類、エチレングリコールモノエチルエーテル、エチレングリコールモノブチルエーテル、ジエチレングリコールモノメチルエーテル、ジエチレングリコールモノエチルエーテル、ジエチレングリコールモノブチルエーテル、トリエチエレングリコールモノメチルエーテル、トリエチレングリコールモノエチルエーテル、トリエチレングリコールモノブチルエーテルなどの多価アルコールのアルキルエーテル類、尿素、２−ピロリドン、Ｎ−メチル−２−ピロリドン、１，３−ジメチル−２−イミダゾリジノンなどがあげられる。
【００８７】
これら湿潤剤の添加量は、インクの０．１〜３０重量％が好ましく、より好ましくは１〜１０重量％の範囲である。
【００８８】
本発明の好ましい態様によればポリマー微粒子のガラス転移点が３０℃以下またはポリマーエマルジョンの最低成膜温度が３０℃以下である場合、沸点が１８０℃以上の水溶性有機溶媒の使用が好ましい。上記水溶性有機溶媒の好ましい例としては、エチレングリコール（沸点：１９７℃；以下括弧内は沸点を示す）、プロピレングリコール（１８７℃）、ジエチレングリコール（２４５℃）、ペンタメチレングリコール（２４２℃）、トリメチレングリコール（２１４℃）、２−ブテン−１，４−ジオール（２３５℃）、２−エチル−１、３−ヘキサンジオール（２４３℃）、２−メチル−２，４−ペンタンジオール（１９７℃）、Ｎ−メチル−２−ピロリドン（２０２℃）、１，３−ジメチル−２−イミダゾリジノン（２５７〜２６０℃）、２−ピロリドン（２４５℃）、グリセリン（２９０℃）、トリプロピレングリコールモノメチルエーテル（２４３℃）、ジプロピレングリコールモノエチルグリコール（１９８℃）、ジプロピレングリコールモノメチルエーテル（１９０℃）、ジプロピレングリコール（２３２℃）、トリエチレングリコルモノメチルエーテル（２４９℃）、テトラエチレングリコール（３２７℃）、トリエチレングリコール（２８８℃）、ジエチレングリコールモノブチルエーテル（２３０℃）、ジエチレングリコールモノエチルエーテル（２０２℃）、ジエチレングリコールモノメチルエーテル（１９４℃）等が挙げられる。本発明の好ましい態様によれば、高沸点水溶性溶媒として、例えば、エチレングリコール、ジエチレングリコール、ペンタメチレングリコール、トリメチレングリコール、２−ブテン−１，４−ジオール、２−エチル−１，３−ヘキサンジオール、２−メチル−２，４−ペンタンジオール、グリセリン、ジプロピレングリコール、テトラエチレングリコール、トリエチレングリコール、Ｎ−メチル−２−ピロリドン、１，３−ジメチル−２−イミダゾリジノン、および２−ピロリドンから選択されるものを使用するのが好ましい。
【００８９】
更に本発明の好ましい態様によれば、本発明によるインク組成物は、糖、三級アミン、水酸化アルカリ、またはアンモニアを含有してなるのが好ましい。これらの添加によって、長期間の保管においても色材の凝集や粘度の上昇がなく保存安定性に優れ、また、開放状態（室温で空気に触れている状態）で放置しても流動性と再分散性を長時間維持し、さらに、印字中もしくは印字中断後の再起動時にノズルの目詰まりが生じることもなく吐出安定性が高いインク組成物が得られる。
【００９０】
本発明によるインク組成物に添加することができる糖は、単糖類、二糖類、オリゴ糖類（三糖類および四糖類を含む）および多糖類があげられ、好ましくはグルコース、マンノース、フルクトース、リボース、キシロース、アラビノース、ガラクトース、アルドン酸、グルシトール、（ソルビット）、マルトース、セロビオース、ラクトース、スクロース、トレハロース、マルトトリオース、などがあげられる。ここで、多糖類とは広義の糖を意味し、アルギン酸、α−シクロデキストリン、セルロースなど自然界に広く存在する物質を含む意味に用いることとする。また、これらの糖類の誘導体としては、前記した糖類の還元糖（例えば、糖アルコール（一般式ＨＯＣＨ₂（ ＣＨＯＨ）ｎＣＨ₂ＯＨ （ここで、ｎ＝２〜５の整数を表す）で表される）、酸化糖（例えば、アルドン酸、ウロン酸など）、アミノ酸、チオ糖などがあげられる。特に糖アルコールが好ましく、具体例としてはマルチトール、ソルビットなどがあげられる。
【００９１】
これら糖類の含有量は、インクの０．１〜４０重量％、より好ましくは１〜３０重量％の範囲である。
【００９２】
本発明によるインク組成物に添加することができるる三級アミンは、トリメチルアミン、トリエチルアミン、トリエタノールアミン、ジメチルエタノールアミン、ジエチルエタノールアミン、トリイソプロペノールアミン、ブチルジエタノールアミン等が挙げられる。これらは、単独で使用しても併用しても構わない。これら三級アミンの本発明のインク組成物への添加量は、０．１〜１０重量％、より好ましくは、０．５〜５重量％である。
【００９３】
本発明によるインク組成物に添加することができる水酸化アルカリは、水酸化カリウム、水酸化ナトリウム、水酸化リチウムであり、本発明のインク組成物への添加量は、０．０１〜５重量％であり、好ましくは０．０５〜３重量％である。
【００９４】
本発明のインク組成物は、さらに界面活性剤を含有することができる。界面活性剤の例としては、アニオン性界面活性剤（例えばドデシルベンゼルスルホン酸ナトリウム、ラウリル酸ナトリウム、ポリオキシエチレンアルキルエーテルサルフェートのアンモニウム塩など）、非イオン性界面活性剤（例えば、ポリオキシエチレンアルキルエーテル、ポリオキシエチレンアルキルエステル、ポリオキシエチレンソルビタン脂肪酸エステル、ポリオキシエチレンアルキルフェニルエーテル、ポリオキシエチレンアルキルアミン、ポリオキシエチレンアルキルアミドなど）および、アセチレングリコール（オレフィンＹ、並びにサーフィノール８２、１０４、４４０、４６５、および４８５（いずれもAir Products and Chemicals Inc.製）が挙げられる。これらは単独使用または二種以上を併用することができる。
【００９５】
本発明のインク組成物には、前記のポリマー微粒子に加えて、汎用のポリマー微粒子をも含むことができる。この汎用のポリマー微粒子はポリマーエマルジョンの形態のものを使用することが好ましい。このポリマー微粒子としては、アクリル系ポリマー、酢酸ビニル系ポリマー、スチレン−ブタジエン系コポリマー、塩化ビニル系ポリマー、アクリル−スチレン系コポリマー、ブタジエン系ポリマー、スチレン系ポリマーなどがあげられる。また、これらのポリマー微粒子の粒子径は２００ｎｍ程度以下が好ましく、より好ましくは５〜２００ｎｍ程度である。これらのポリマー微粒子はポリマーエマルジョンの形態として市販されているものを使用することも可能であり、例えばマイクロジェルＥ−１００２、Ｅ−５００２（スチレン−アクリル系ポリマーエマルジョン、日本ペイント株式会社製）、ボンコート４００１（アクリル系ポリマーエマルジョン、大日本インキ化学工業株式会社製）ボンコート５４５４（スチレン−アクリル系ポリマーエマルジョン、大日本インキ化学工業株式会社製）、ＳＡＥ−１０１４（スチレン−アクリル系ポリマーエマルジョン、日本ゼオン株式会社製）、サイビノールＳＫ−２００（アクリル系ポリマーエマルジョン、サイデン化学株式会社製）、などがあげられる。
【００９６】
その他、必要に応じて、ｐＨ調整剤、防腐剤、防かび剤、りん系酸化防止剤等を添加しても良い。
【００９７】
本発明によるインク組成物は、前記成分を適当な方法で分散、混合することによって製造することができる。好ましくは、まず顔料と高分子分散剤と水を適当な分散機（例えば、ボールミル、サンドミル、アトライター、ロールミル、アジテータミル、ヘンシェルミキサー、コロイドミル、超音波ホモジナイザー、ジェットミル、オングミルなど）で混合し、均一な顔料分散液を調製し、次いで、水に、沸点が１８０℃以上の水溶性有機溶媒、糖、ｐＨ調整剤、防腐剤、防かび剤等を加えて充分溶解させた後、前記のポリマー微粒子を分散粒子とするポリマーエマルジョンを加え適当な分散機で常温で充分に攪拌してインク溶媒を調製する。前記顔料分散液を適当な分散機で攪拌しながら、前記のインク溶媒を徐々に滴下し、さらに充分攪拌する。充分に撹拌した後に、目詰まりの原因となる粗大粒子および異物を除去するためにろ過を行って目的のインク組成物を得る。
【００９８】
５．インクジェット記録方法
本発明によるインク組成物は、上記の通りインクジェット記録方法に好ましく用いられる。さらに本発明によるインク組成物は、複数のカラーインク組成物を用いたカラーインクジェット記録方法に好ましく用いられる。このカラーインクジェット記録方法を図面を用いて説明する。
【００９９】
図１のインクジェット記録装置は、インク組成物をタンクに収納し、インク組成物がインクチューブを介して記録ヘッドに供給される態様である。すなわち、記録ヘッド１とインクタンク２とがインクチューブ３で連通される。ここで、インクタンク２は内部が区切られており、インク組成物、場合によって複数のカラーインク組成物の部屋が設けられてなる。
【０１００】
記録ヘッド１は、キャリッジ４に沿って、モーター５で駆動されるタイミングベルト６によって移動する。一方、記録媒体である紙７はプラテン８およびガイド９によって記録ヘッド１と対面する位置に置かれる。なお、この態様においては、キャップ１０が設けられてなる。キャップ１０には吸引ポンプ１１が連結され、いわゆるクリーニング操作を行なう。吸引されたインク組成物はチューブ１２を介して廃インクタンク１３に溜め置かれる。
【０１０１】
記録ヘッド１のノズル面の拡大図を図２に示す。１ｃで示される部分がインク組成物のノズル面であって、ノズル２２、２３、２４、２５からはそれぞれイエローインク組成物、マゼンタインク組成物、シアンインク組成物、そしてブラックインク組成物が吐出される。
【０１０２】
さらに、この図２に記載の記録ヘッドを用いたインクジェット記録方法を図３を用いて説明する。記録ヘッド１は矢印Ａ方向に移動する。その移動の間に、インク組成物を印字し、印字領域３１を形成する。
【０１０３】
さらに、インクジェット記録装置には、インク組成物の補充がインクタンクであるカートリッジを取り替えることで行なわれるものがある。また、このインクタンクは記録ヘッドと一体化されたものであってもよい。
【０１０４】
このようなインクタンクを利用したインクジェット記録装置の好ましい例を図４に示す。図中で図１の装置と同一の部材については同一の参照番号を付した。図４の態様において、記録ヘッド１は、インクタンク２と一体化されてなる。印字方法には基本的に図１の装置と同様であってよい。そして、この態様において、記録ヘッド１とインクタンク２は、キャリッジ４上をともに移動する。
【０１０５】
６．二液を用いた記録方法
さらに、本発明の好ましい態様によれば、本発明によるインク組成物は、インク組成物と、このインク組成物と接触して凝集物を生成する反応剤を含んでなる反応液との二つの液を用いた記録方法に好ましく用いられる。この方法によれば、定着性に優れ、指触性および耐擦性、耐水性に優れ、良好なＯＤ値と光沢性を有する画像を得ることができる。その理由は、色材およびポリマーエマルジョンの分散状態を、反応剤が崩壊させ、凝集物を生じさせ、紙等の記録媒体に対して優れた定着性と、高いＯＤ値と光沢性を有し、フェザリングやブリード、滲みのない高品位の画像が実現されるものと思われる。
【０１０６】
本発明によるインク組成物と接触して凝集物を生成する反応剤の例としては、多価金属塩および／またはポリアリルアミンおよび／またはその誘導体が挙げられる。
【０１０７】
多価金属塩としては、２価以上の多価金属イオンと、これら多価金属イオンに結合する陰イオンとから構成され、水に可溶のものを使用する。多価金属イオンの具体例としては、Ｃａ²⁺、Ｃｕ²⁺、Ｎｉ²⁺、Ｍｇ²⁺、 Ｚｎ²⁺、Ｂａ²⁺などの二価金属イオン、Ａｌ³⁺、Ｆｅ³⁺、Ｃｒ³⁺などの三価金属イオンがあげらる。陰イオンの具体例としては、Ｃｌ^-、ＮＯ₃ ^-、Ｉ^-、 Ｂｒ^-、 ＣｌＯ₃ ^-およびＣＨ₃ＣＯＯ^- などがあげられ、好ましくは、硝酸イオンまたはカルボン酸イオンである。ここで、カルボン酸イオンは、好ましくは炭素数１〜６の飽和脂肪族モノカルボン酸および炭素数７〜１１の炭素環式モノカルボン酸からなる群から選択されるカルボン酸から誘導されるものである。炭素数１〜６の飽和脂肪族モノカルボン酸の好ましい例としては、蟻酸、酢酸、プロピオン酸、イソ酪酸、吉草酸、イソ吉草酸、ピバル酸、ヘキサン酸などが挙げられる。特に蟻酸、酢酸が好ましい。このモノカルボン酸の飽和脂肪族炭化水素基上の水素原子は水酸基で置換されていてもよく、そのようなカルボン酸の好ましい例としては、安息香酸、ナフトエ酸等が挙げられ、より好ましくは安息香酸である。
【０１０８】
また、ポリアリルアミンおよびポリアリルアミン誘導体は、水に可溶で、水中でプラスに荷電するカチオン系高分子である。例えば、式（ａ）、式（ｂ）、式（ｃ）が挙げられる。
【０１０９】
【化１５】

（式中、Ｘ^-は塩化物イオン、臭化物イオン、ヨウ化物イオン、硝酸イオン、燐酸イオン、硫酸イオン、酢酸イオン等を表わす。）
更に、アリルアミンとジアリルアミンが共重合したポリマーやジアリルメチルアンモニウムクロライドと二酸化硫黄との共重合体を使用することができる。
【０１１０】
本発明において用いられる反応液は、基本的に多価金属塩および／またはポリアリルアミンおよび／またはポリアリルアミン誘導体と、水とを含んでなるものである。
【０１１１】
かかる反応液中の前記多価金属塩の濃度は印字品質、目詰まり防止の効果が得られる範囲で適宜決定されてよいが、好ましくは反応液の０．１から４０重量％程度であり、より好ましくは５から２５重量％程度である。また、かかる反応液中の前記ポリアリルアミンおよび／またはポリアリルアミン誘導体の濃度は、反応液の０．５から１０重量％であることが好ましい。。
【０１１２】
また、本発明において反応液には、高沸点有機溶媒などの湿潤剤を含んでなることが好ましい。高沸点有機溶媒の好ましい例としては、インク組成物の項で記載したものが挙げられる。高沸点有機溶媒は、反応液の乾燥を防ぐことによりヘッドの目詰まりを防止する。
【０１１３】
高沸点有機溶媒の添加量は特に限定されないが、好ましくは ０．５〜４０重量％程度であり、より好ましくは２〜２０重量％程度である。
【０１１４】
本発明のより好ましい態様によれば、高沸点有機溶媒としてトリエチレングリコールモノブチルエーテル、グリセリンを添加するのが好ましい。これらを組み合わせて添加する場合、トリエチレングリコールモノブチルエーテルおよびグリセリンの添加量はそれぞれ１０〜２０重量％程度および１〜１５重量％程度が好ましい。また、この反応液は、前記の界面活性剤を添加してもよい。その他、保存安定性を向上させるために、必要に応じて反応液にアンモニア等のｐＨ調整剤、防腐剤、防かび剤等を添加しても良い。
【０１１５】
また、この反応液は、カラー色材を添加して着色され、インク組成物の機能を兼ね備えたものとしてもよい。
【０１１６】
反応液の記録媒体への付着に関しては、インク組成物を付着させる場所のみ選択的に反応液を付着させる方法と、紙全体に反応液を付着させる方法のいずれの態様であってもよい。前者が反応液の消費量を必要最小限に抑えることができ経済的であるが、反応液とインク組成物双方を付着させる位置にある程度の精度が要求される。一方、後者は、前者に比べ反応液およびインク組成物の付着位置の精度の要求は緩和されるが、紙全体に大量の反応液を付着させることとなり、乾燥の際、紙がカールしやすい。従って、いずれの方法を採用するかは、インク組成物と反応液との組み合わせを考慮して決定されてよい。
【０１１７】
本発明の好ましい態様によれば、上記インク組成物と反応液とは、いわゆるインクジェット記録方法によって記録媒体に適用されるのが好ましい。すなわち、インクジェット記録ヘッドのインク吐出孔から液滴を吐出し、記録媒体に付着させて画像を形成する記録方法が好ましい。
【０１１８】
本発明によるインク組成物と反応液を用いたインクジェット記録方法をさらに図面を用いて説明する。
【０１１９】
図５のインクジェット記録装置は、インク組成物および反応液をタンクに収納し、インク組成物および反応液がインクチューブを介して記録ヘッドに供給される態様である。すなわち、記録ヘッド５１とインクタンク５２とがインクチューブ３で連通される。ここで、インクタンク５２は内部が区切られており、インク組成物、場合によって複数のカラーインク組成物の部屋と反応液の部屋とが設けられてなる。
【０１２０】
記録ヘッド５１は、キャリッジ４に沿って、モーター５で駆動されるタイミングベルト６によって移動する。一方、記録媒体である紙７はプラテン８およびガイド９によって記録ヘッド５１と対面する位置に置かれる。なお、この態様においては、キャップ１０が設けられてなる。キャップ１０には吸引ポンプ１１が連結され、いわゆるクリーニング操作を行なう。吸引されたインク組成物はチューブ１２を介して廃インクタンク１３に溜め置かれる。
【０１２１】
記録ヘッド５１のノズル面の拡大図を図６に示す。５１ｂで示される部分が反応液のノズル面であって、反応液が吐出されるノズル２１が縦方向に設けられてなる。一方、５１ｃで示される部分がインク組成物のノズル面であって、ノズル２２、２３、２４、２５からはそれぞれイエローインク組成物、マゼンタインク組成物、シアンインク組成物、そしてブラックインク組成物が吐出される。
【０１２２】
さらに、この図６に記載の記録ヘッドを用いたインクジェット記録方法を図７を用いて説明する。記録ヘッド５１は矢印Ａ方向に移動する。その移動の間に、ノズル面５１ｂより反応液が吐出され、記録媒体７上に帯状の反応液付着領域６１を形成する。次に、記録媒体７が紙送り方向矢印Ｂに所定量移送される。その間記録ヘッド５１は図中で矢印Ａと逆方向に移動し、記録媒体７の左端の位置に戻る。そして、既に反応液が付着している反応液付着領域にインク組成物を印字し、印字領域６２を形成する。
【０１２３】
また、図８に記載のように記録ヘッド５１において、ノズルを全て横方向に並べて構成することも可能である。図中で、４１ａおよび４１ｂは反応液の吐出ノズルであり、ノズル４２、４３、４４、４５からはそれぞれイエローインク組成物、マゼンタインク組成物、シアンインク組成物、そしてブラックインク組成物が吐出される。このような態様の記録ヘッドにおいては、記録ヘッド５１がキャリッジ上を往復する往路、復路いずれにおいても印字が可能である点で、図７に示される記録ヘッドを用いた場合よりも速い速度での印字が期待できる。
【０１２４】
さらに、インクジェット記録装置には、インク組成物の補充がインクタンクであるカートリッジを取り替えることで行なわれるものがある。また、このインクタンクは記録ヘッドと一体化されたものであってもよい。
【０１２５】
このようなインクタンクを利用したインクジェット記録装置の好ましい例を図９に示す。図中で図１の装置と同一の部材については同一の参照番号を付した。図９の態様において、記録ヘッド５１ａおよび５１ｂは、インクタンク５２ａおよび５２ｂと一体化されてなる。記録ヘッド５１ａまたは５１ｂをそれぞれインク組成物および反応液を吐出するものとする。印字方法には基本的に図５の装置と同様であってよい。そして、この態様において、記録ヘッド５１ａとインクタンク５２ａおよび記録ヘッド５１ａおよびインクタンク５２ｂは、キャリッジ４上をともに移動する。
【０１２６】
【実施例】
ポリマーエマルジョン１
撹拌機、還流冷却器、滴下装置、および温度計と窒素導入管を備えた反応容器に、蒸留水２００ｍｌ、ドデシルベンゼンスルホン酸ナトリウム０．６ｇを仕込み、窒素雰囲気中で、撹拌しながら７０℃まで加温し、さらに過硫酸カリウム２ｇを添加する。一方、ブチルアクリレート４０ｇ、スチレン５０ｇ、アクリルアミド５ｇ、アクリル酸５ｇ、ｔ−ドデシルメルカプタン０．１５ｇ、および紫外線吸収剤２（２’−ヒドロキシ−５’−メチルフェニル）ベンゾトリアゾール（シプロ化成製ＳＥＥＳＯＲＢ７０９）１ｇを混合溶解して、これを前記反応容器中に滴下する。さらに、７０℃で６時間反応させた後、常温まで冷却し、中和剤としてアンモニア水を添加してＰＨを調製し、１０μｍのフィルターで濾過して、紫外線吸収剤を含有するポリマー微粒子を分散粒子とするポリマーエマルジョンを得る。このポリマーエマルジョンのガラス転移点は２０℃で最低成膜温度は２５℃である。
【０１２７】
ポリマーエマルジョン２
撹拌機、還流冷却器、滴下装置および温度計と窒素導入管を備えた反応容器に、蒸留水２００ｍｌ、ドデシルベンゼンスルホン酸ナトリウム０．６ｇを仕込み、窒素雰囲気中で、撹拌しながら７０℃まで加温し、さらに過硫酸カリウム２ｇを添加する。一方、ブチルアクリレート４０ｇ、スチレン５０ｇ、アクリルアミド５ｇ、アクリル酸５ｇ、ｔ−ドデシルメルカプタン０．１ｇと、紫外線吸収能を有する骨格を持つモノマー２（２’−ヒドロキシ−５’−メタクリロキシエチルフェニル）−２Ｈ−ベンゾトリアゾール （大塚化学製ＲＵＶＡ−９３）を５ｇと光安定化能を有する骨格を持つモノマー１，２，２，６，６−ペンタメチル−４−ピペリジルメタクリレート（旭電化製アデカスタブＬＡ−８２）１ｇを混合溶解して、これを前記反応容器中に滴下する。さらに７０℃で６時間反応させた後、常温まで冷却し、中和剤としてアンモニア水を添加してｐＨを調製し、１０μｍのフィルターで濾過して、紫外線吸収能および光安定能を有する部位を構造中に有するポリマー微粒子を分散粒子とするポリマーエマルジョンを得る。このポリマーエマルジョンのガラス転移点は２０℃で最低成膜温度は２５℃であった。
【０１２８】
ガラス転移点の測定
前記ポリマーエマルジョンの水分を乾燥させて得られたフィルムを示差走査熱量測定装置（ＤＳＣ）にて昇温速度１０℃／ｍｉｎで測定する。
【０１２９】
最低成膜温度の測定
最低成膜温度測定装置をセットし、アルミニウム製の試料板上の温度勾配が平衡に達したところで、試料の前記ポリマーエマルジョンを薄く延ばして乾燥させる。乾燥終了後に試料板上を観察すると、最低成膜温度以上の温度領域では透明な連続フィルムが形成されるが、最低成膜温度以下の温度領域では白色粉末状となる。この境界の温度を最低成膜温度として測定する。
【０１３０】

【０１３１】

【０１３２】

【０１３３】
上記のインクの調製は以下の通り行う。
まず、顔料と分散剤と水を混合し、サンドミル（安川製作所製）中で、ガラスビーズ（直径１．７ｍｍ、混合物の１．５倍量（重量））とともに２時間分散させた後、ガラスビーズを取り除き顔料分散液を調製する。次いで、水に上記ポリマーエマルジョン１、グリセリン、マルチトール、２−ピロリドン、トリエタノールアミン、水酸化カリウムを加え、常温で２０分間攪拌した後に、攪拌した状態で上記の顔料分散液を徐々に滴下し、さらに２０分間攪拌する。これを、５μｍのメンブランフィルターでろ過し、インクジェット記録用インクを得る。
【０１３４】

【０１３５】

【０１３６】

上記のインクの調製はカラーインク１と同様の方法で行った。
【０１３７】
カラーインク３
本インクは、上記の紫外線吸収能を有する部位を構造中に有するポリマー微粒子を分散粒子とする市販のポリマーエマルジョン ＢＡＳＦ製ＵＶＡ−３８３ＭＡを用いた。かかるポリマー微粒子は２−ヒドロキシ−４−（メタクリロイルオキシエトキシ）ベンゾフェノンを紫外線吸収能を有する部位を持つモノマーとして共重合成分として用いられており、ガラス転移点は約２７℃でかかるポリマーエマルジョンの最低成膜温度は０℃以下である。
【０１３８】

【０１３９】

【０１４０】

上記のインクの調製はカラーインク１と同様の方法で行った。
【０１４１】

【０１４２】

【０１４３】

上記のインクの調製はカラーインク１と同様の方法で行う。
【０１４４】

【０１４５】

【０１４６】

【０１４７】
上記のインクの調製はカラーインク１と同様の方法で行う。
【０１４８】
反応液の調製
（反応液１）
硝酸マグネシウム・六水和物 ２５重量％
トリエチレングリコール
モノブチルエーテル １０重量％
グリセリン ２０重量％
純水 残量
【０１４９】
（反応液２）
式（ａ）で示されるポリアリルアミン ５重量％
トリエチレングリコール
モノブチルエーテル １０重量％
グリセリン ２０重量％
純水 残量
【０１５０】
評価試験
評価１：耐光性
（印字方法）
図１のインクジェット記録装置を用いて、カラーインク１〜５のイエロー、マゼンタ、シアンの各インクを普通紙Ｘｅｒｏｘ ４０２４、Ｘｅｒｏｘ Ｐおよびインクジェット専用紙（セイコーエプソン（株）製）に１００％ｄｕｔｙで印字し、３ｃｍ×３ｃｍのベタ画像を得る。
実施例１：上記の印字方法でカラーインク１を用いて得られる記録物。
実施例２：上記の印字方法でカラーインク２を用いて得られる記録物。
実施例３：上記の印字方法でカラーインク３を用いて得られる記録物。
比較例１：上記の印字方法でカラーインク４を用いて得られる記録物。
比較例２：上記の印字方法でカラーインク５を用いて得られる記録物。
図５のインクジェット記録装置を用いて、反応液１とカラーインク１〜５のイエロー、マゼンタ、シアンの各インクを普通紙Ｘｅｒｏｘ ４０２４、Ｘｅｒｏｘ Ｐおよびインクジェット専用紙（セイコーエプソン（株）製）に１００％ｄｕｔｙで印字し、３ｃｍ×３ｃｍのベタ画像を得る。
実施例４：上記の印字方法で反応液１とカラーインク１を用いて得られる記録物。
実施例５：上記の印字方法で反応液１とカラーインク２を用いて得られる記録物。
実施例６：上記の印字方法で反応液１とカラーインク３を用いて得られる記録物。
比較例３：上記の印字方法で反応液１とカラーインク４を用いて得られる記録物。
比較例４：上記の印字方法で反応液１とカラーインク５を用いて得られる記録物。
【０１５１】
評価方法
上記の方法で得られるベタ画像の記録物をキセノンフェードメーターを用い６００時間の暴露試験を行う。ベタ画像部分の暴露前の色と暴露後の色を、Ｍａｃｂｅｔｈ ＣＥ−７０００分光光度計（Ｍａｃｂｅｔｈ製）で測定し、ＣＩＥで規定されるＬ＊ａ＊ｂ＊色差表示法で示し、ベタ画像部分の暴露前後の色変化を次式で求める色差で表わす。
色差：ΔＥ＊ａｂ＝［（ΔＬ＊）²＋（Δａ＊）²＋（Δｂ＊）²］^1/2
その値を以下の基準で評価する。

また、ベタ画像部分の暴露前の色濃度と暴露後の色濃度を、Ｍａｃｂｅｔｈ 濃度計ＴＲ９２７（Ｍａｃｂｅｔｈ製）で測定し、ベタ画像部分の暴露前後の色濃度変化を以下の基準で評価する。

評価結果は次の表に示される通りである。
【表１】

【表２】

【０１５２】
評価２：印字品質（にじみ）
図５のインクジェット記録装置を用いて、反応液１または反応液２とカラーインク１〜５のイエロー、マゼンタ、シアンの各インクで以下の各紙に印刷を行う。その組み合わせは下記の通りである。
実施例７：上記の印字方法で反応液１とカラーインク１を用いて得られる記録物。
実施例８：上記の印字方法で反応液１とカラーインク２を用いて得られる記録物。
実施例９：上記の印字方法で反応液２とカラーインク１を用いて得られる記録物。
実施例１０：上記の印字方法で反応液２とカラーインク２を用いて得られる記録物。
比較例５：上記の印字方法でカラーインク４を用いて得られる記録物。
比較例６：上記の印字方法で反応液１とカラーインク５を用いて得られる記録物。
印刷は、まず反応液を１００％ｄｕｔｙで印刷した後、各色のカラーインクでアルファベット２４文字を印刷する。反応液、インクともに吐出量は０．０７μｇ／ｄｏｔ、密度は３６０ｄｐｉとする。
評価に使用する記録紙は以下の通りである。
▲１▼Ｘｅｒｏｘ Ｐ紙（ゼロックス株式会社製）
▲２▼Ｒｉｃｏｐｙ ６２００紙（リコー株式会社製）
▲３▼Ｘｅｒｏｘ ４０２４紙（ゼロックス株式会社製）
▲４▼Ｎｅｅｎａｈ Ｂｏｎｄ紙（キンバリークラーク社製）
▲５▼Ｘｅｒｏｘ Ｒ紙（ゼロックス株式会社製・再生紙）
▲６▼やまゆり紙（本州製紙株式会社製・再生紙）
得られた記録物の文字におけるにじみの発生の有無を目視で観察し、以下のように評価する。
◎：全紙ににじみの発生なく鮮明な文字が得られている。
○：一部の用紙にひげ状のにじみの発生がある。
△：全紙にひげ状のにじみがある。
×：文字の輪郭がはっきりしないほどにじみが発生している。
評価結果は次の表に示されるとおりである。
【表３】

【０１５３】
評価３：耐擦性試験（耐ラインマーカー性）
評価２で印字した記録物を２４時間常温で乾燥させた後に、ゼブラ社水性蛍光ペン ＺＥＢＲＡ ＰＥＮ２（商標）を用いて、かかる記録物の印刷文字を筆圧４．９×１０⁵Ｎ／ｍ²で擦り、汚れの有無を目視で観察し、次のように評価する。
○：２回擦っても全く汚れが生じない。
×：１回の擦りでは汚れが生じる。
この評価結果は、次の表に示されるとおりであった。
【表４】

【０１５４】
評価４：カラーブリード
図５のインクジェット記録装置を用いて、反応液１とカラーインク１〜５のイエロー、マゼンタ、シアンの各インクで以下の各紙に印刷を行う。その組み合わせは下記の通りである。
実施例１１：上記の印字方法で反応液１とカラーインク１を用いて得られる記録物。
実施例１２：上記の印字方法で反応液１とカラーインク２を用いて得られる記録物。
実施例１３：上記の印字方法で反応液２とカラーインク１を用いて得られる記録物。
比較例７：上記の印字方法で反応液は用いないで、カラーインク４のみを用いて得られる記録物。
比較例８：上記の印字方法で反応液１とカラーインク５を用いて得られる記録物。
また、評価に使用する記録紙を以下に示す。
▲１▼Ｘｅｒｏｘ Ｐ紙（ゼロックス株式会社製）
▲２▼Ｒｉｃｏｐｙ ６２００紙（リコー株式会社製）
▲３▼Ｘｅｒｏｘ ４０２４紙（ゼロックス株式会社製）
▲４▼Ｎｅｅｎａｈ Ｂｏｎｄ紙（キンバリークラーク社製）
▲５▼Ｘｅｒｏｘ Ｒ紙（ゼロックス株式会社製・再生紙）
▲６▼やまゆり紙（本州製紙株式会社製・再生紙）
印刷は、まず反応液を１００％ｄｕｔｙで印刷した後、カラーインクの各色（シアン、マゼンタ、イエロー）を印字する。各色の境界部分での不均一な色の混じりの発生の有無を目視で観察し、以下の基準で評価する。反応液、インクともに吐出量は０．０７μｇ／ｄｏｔ、密度は３６０ｄｐｉとする。
○：色の混じりがなく境界が鮮明な場合
△：ひげ状に色の混じりが発生した場合
×：境界がはっきりしないほど色が混じった場合
評価結果は次の表に示されるとおりである。
【表５】

【０１５５】
評価５：保存安定性
ガラス製サンプル瓶に以下のインク組成物５０ｃｃを入れ、６０℃で２週間放置し、粘度、沈降物および異物の発生の有無を調べる。
実施例１５：カラーインク１を本試験に供した。
実施例１６：カラーインク２を本試験に供した。
実施例１７：カラーインク３を本試験に供した。
比較例９：カラーインク４を本試験に供した。
比較例１０：カラーインク５を本試験に供した。
評価は以下のように行う。
○：沈降物、異物の発生がなく、粘度変化もない。
△：沈降物、異物の発生ないが、粘度変化がある。
×：沈降物または異物の発生がある。
この評価結果は、第７表に示されるとおりであった。
【０１５６】
評価６：目詰まり信頼性
図１のインクジェット記録装置のヘッドに、カラーインク１〜５のイエロー、マゼンタ、シアンの各インクをそれぞれ充填し、１０分間連続して英数文字を印刷する。その後、プリンターを停止し、キャップをせずに、温度４０℃、湿度２５％の環境下で、１週間放置する。放置後に再び英数文字を印刷し、放置前と同等の印字品質が得られるまでに要した復帰動作の回数を調べる。
なお、試験に供するインク組成物は以下の通りである。
実施例１５：カラーインク１を本試験に供した。
実施例１６：カラーインク２を本試験に供した。
実施例１７：カラーインク３を本試験に供した。
比較例９：カラーインク４を本試験に供した。
比較例１０：カラーインク５を本試験に供した。
評価の判定は以下の基準に従い行う。
０〜２回の復帰動作で初期と同等の印字品質が得ら
れた。 ：○
３〜５回の復帰動作で初期と同等の印字品質が得ら
れた。 ：△
６回以上の復帰動作で初期と同等の印字品質が得ら
れなかった。 ：×
この評価結果は、第７表に示されるとおりである。
【０１５７】
評価７：吐出安定性
インクジェットプリンターＭＪ−７００Ｖ２Ｃ（セイコーエプソン株式会社製）にインク組成物を充填し、吐出量は０．７μｇ／ｄｏｔ、密度は３６０ｄｐｉで、常温でアルファベット文字を連続印字する。ドット抜け、およびインクの飛び散りを観察し、１０回以上発生するまでの時間を調べる。
なお、試験に供するインク組成物は以下の通りである。
実施例１５：カラーインク１を本試験に供した。
実施例１６：カラーインク２を本試験に供した。
実施例１７：カラーインク３を本試験に供した。
比較例９： カラーインク４を本試験に供した。
比較例１０：カラーインク５を本試験に供した。
評価は以下のように行う。
４８時間以上ドット抜け、またはインクの飛び散りが
１０回発生しない。 ：◎
２４〜４８時間の内にドット抜け、またはインクの飛
び散りが１０回発生する。 ：○
１〜２４時間の内にドット抜け、またはインクの飛び
散りが１０回発生する。 ：△
１時間以内にドット抜け、またはインクの飛び散りが
１０回以上発生する。 ：×
この評価結果は、次の表に示されるとおりである。
【表６】

【図面の簡単な説明】
【図１】本発明による方法を実施するインクジェト記録装置を示す図であって、この態様においては記録ヘッドとインクタンクがそれぞれ独立してなり、インク組成物はインクチューブにより記録ヘッドに供給される。
【図２】記録ヘッドのノズル面の拡大図であり、１ｃが、インク組成物が吐出される複数のノズルが縦方向に並んで設けられてなるノズル面である。
【図３】 図２の記録ヘッドを用いたインクジェット記録を説明する図である。図中で、３１はインク組成物が印字されたものである。
【図４】 本発明による方法を実施するインクジェット記録装置を示す図であって、この態様においては記録ヘッドとインクタンクが一体化されてなる。
【図５】 本発明による方法を実施するインクジェト記録装置を示す図であって、この態様においては記録ヘッドとインクタンクがそれぞれ独立してなり、インク組成物および反応液はインクチューブにより記録ヘッドに供給される。
【図６】記録ヘッドのノズル面の拡大図であって、５１ｂが反応液のノズル面であり、５１ｃがインク組成物のノズル面である。
【図７】図２の記録ヘッドを用いたインクジェット記録を説明する図である。図中で、６１は反応液付着領域であり、６２は反応液が付着した上にインク組成物が印字された印字領域である。
【図８】記録ヘッドの別の態様を示す図であって、吐出ノズルがすべて横方向に並べて構成されたものである。
【図９】本発明による方法を実施するインクジェット記録装置を示す図であって、この態様においては記録ヘッドとインクタンクが一体化されてなる。
【符号の説明】
１，５１ 記録ヘッド
２，５２ インクタンク
３ インクチューブ
２２，２３，２４，２５ インク吐出ノズル
３１ 印字領域
２１ 反応液吐出ノズル
６１ 反応液付着領域
６２ 印字領域[0001]
BACKGROUND OF THE INVENTION
Field of Invention
The present invention relates to an ink composition, and more particularly to an ink composition preferably used in an ink jet recording method.
[0002]
Background art
In the recording method using the ink composition, a solvent component that dissolves or disperses the coloring material is essential. As the solvent component, a mixed solvent of water and a water-soluble organic solvent is widely used from the viewpoint of safety. When the ink composition is applied onto the recording medium, the solvent component penetrates into the recording medium or evaporates, thereby fixing the color material component onto the recording medium and recording characters or images. Various performances are required for the obtained image.
[0003]
Among these required performances, various proposals have been made for light resistance in order to improve the performance. Water-soluble dyes are frequently used as coloring materials for water-based ink compositions because of their good water solubility, but it has been pointed out that they are generally poor in light resistance. In view of this, an ink composition in which a water-insoluble colorant such as a pigment having excellent light resistance is dispersed has been proposed.
[0004]
However, it has been pointed out that although inorganic pigments such as carbon black and metal-containing organic pigments such as copper phthalocyanine pigments are excellent in light resistance, many other organic pigments cannot provide sufficient light resistance. Therefore, it can be said that a method for improving the light resistance of an ink composition using such an organic pigment as a coloring material is desired. In addition, the variety of dyes that can be used is attractive, and there has been a demand for a technique that can improve the light resistance of an image even in an ink composition that contains a dye as a coloring material.
[0005]
Recently, a color image is formed with a plurality of ink compositions. In a color image using such a plurality of ink compositions, if even one color is inferior in light resistance, the hue of the image changes and the quality of the color image is extremely deteriorated. Therefore, the color ink composition requires more controlled light resistance.
[0006]
Recently, ink jet recording printers have begun to spread widely. This inkjet recording method is a printing method in which printing is performed by causing small droplets of an ink composition to fly and adhere to a recording medium such as paper. This method has a feature that a high-resolution and high-quality image can be printed at a high speed with a relatively inexpensive apparatus. In particular, the color ink jet recording apparatus has improved image quality, is used as a photographic output machine, and has been used as a digital printing machine, a plotter, a CAD output device, and the like. Images printed by such inkjet printers that have been widely used can be used in various forms, especially photographic prints that are exposed to direct sunlight such as fluorescent light or outdoors for a long time as a display. It is possible to be placed in a place where Therefore, light resistance is an extremely important required performance in the ink composition used in the ink jet recording method.
[0007]
As a means for improving the light resistance of the ink composition, an ultraviolet absorber or a light stabilizer may be added to the ink composition. However, since many of the ultraviolet absorbers and light stabilizers are oil-soluble, it is difficult to make a sufficient amount present in the water-soluble ink composition.
[0008]
On the other hand, as an ink jet recording method, a new method has recently been proposed in which a polyvalent metal salt solution is applied to a recording medium and then an ink composition containing a dye having at least one carboxyl group is applied (for example, a special feature). Kaihei 5-202328). In this method, an insoluble complex is formed from a polyvalent metal ion and a dye, and the presence of this complex is said to provide a high-quality image having water resistance and no color bleeding.
[0009]
Further, by using a combination of a color ink containing a surfactant or a penetrating solvent and a salt that imparts at least permeability and a black ink that thickens or aggregates due to the action of this salt, the image density is increased. A proposal has also been made that a high-quality color image without color bleeding can be obtained (Japanese Patent Laid-Open No. 6-106735). That is, an ink jet recording method has been proposed in which a good image can be obtained by printing two liquids, a first liquid containing salt and an ink composition.
[0010]
In addition, an ink jet recording method for printing two liquids has been proposed (for example, JP-A-3-240557 and JP-A-3-240558).
[0011]
SUMMARY OF THE INVENTION
The present inventors have recently improved the light resistance of an ink composition by adding a polymer having ultraviolet absorption ability and / or light stabilization ability and having a film-forming ability as fine particles to the ink composition. Suggest a method.
[0012]
That is, an object of the present invention is to provide an ink composition that realizes a printed image having excellent light resistance.
[0013]
More specifically, the present invention provides an ink composition capable of obtaining not only light resistance but also scratch resistance, water resistance, and an excellent print quality image free from bleeding and color bleeding. It is aimed.
[0014]
Another object of the present invention is to provide an ink composition that is excellent in ejection stability and storage stability when used in an ink jet recording method.
[0015]
Still another object of the present invention is to provide an ink composition capable of obtaining an image having a good quality, particularly an image free from bleeding and color bleeding, in a recording method using so-called two liquids.
[0016]
The ink composition according to the present invention is an ink composition comprising a coloring material, water, a water-soluble organic solvent, and polymer fine particles, and the polymer fine particles have a film-forming ability, and It consists of a polymer having ultraviolet absorbing ability and / or light stabilizing ability.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
1.Ink composition
The ink composition according to the present invention is used in a recording system using the ink composition. Examples of the recording method using the ink composition include an ink jet recording method, a recording method using a writing instrument such as a pen, and other various printing methods. In particular, the ink composition according to the present invention is preferably used in an ink jet recording method.
[0018]
The ink composition according to the present invention basically comprises a color material, water, a water-soluble organic solvent, and polymer fine particles. The polymer fine particles are made of a polymer having a film forming ability and an ultraviolet absorbing ability and / or a light stabilizing ability.
[0019]
2.Bolimer fine particles
The polymer fine particles used in the ink composition according to the present invention have a film forming ability.
[0020]
In the present invention, the polymer fine particles having film-forming ability mean those that form a homogeneous film when the ink composition containing the polymer fine particles is dried. The following theory is only an assumption, and the reason why the ink composition according to the present invention realizes an image excellent in light resistance on the condition that the present invention is not limited to the following theory is as follows. When the ink composition according to the present invention adheres to the recording medium, the solvent component penetrates into the recording medium or evaporates, and fixes the color material on the recording medium. At that time, since the polymer fine particles contained in the ink composition have a film forming ability, a film covering the color material component is formed. Since this film is made of a polymer having ultraviolet absorption ability and / or light stabilization ability, it has ultraviolet absorption ability and / or light stabilization ability. More specifically, when the color material is a pigment, a film in which the pigment is dispersed is formed. Since the ultraviolet rays are blocked by this film and do not reach the pigment in the film, the image has light resistance. When the coloring material is a dye, a film in which the dye is incorporated is formed on the surface of the recording medium, and a part of the dye is dyed on the recording medium and fixed therein. Since the ultraviolet rays are blocked by this film and do not reach the layer of the recording medium on which the dye in or under the film is fixed, the image is considered to have light resistance.
[0021]
According to a preferred embodiment of the present invention, the particle size of the polymer fine particles is preferably about 5 nm to 200 nm, more preferably about 5 nm to 100 nm.
[0022]
Further, the content of the polymer fine particles in the ink composition according to the present invention is preferably about 1 to 10% by weight, more preferably 1 to 5% by weight of the ink composition.
According to a preferred embodiment of the present invention, the polymer fine particles preferably have a single particle structure. According to still another preferred embodiment, the polymer fine particles preferably have a core-shell structure comprising a core portion and a shell layer surrounding the core portion.
[0023]
According to a preferred embodiment of the present invention, the polymer fine particles are preferably dispersed in the ink composition as dispersed particles of a polymer emulsion. That is, in preparing the ink composition according to the present invention, the polymer fine particles are preferably mixed with the components constituting the ink composition in the form of a polymer emulsion. According to a preferred embodiment of the present invention, the particle size of the polymer fine particles in the polymer emulsion is preferably about 200 nm or less, more preferably about 5 to 100 nm.
According to a preferred embodiment of the present invention, the polymer constituting the polymer fine particles preferably has a glass transition point of 30 ° C. or lower. By using such a polymer, the ink composition according to the present invention forms a film more reliably at room temperature.
[0024]
Furthermore, according to a preferred aspect of the present invention, when the polymer fine particles are dispersed in the ink composition as dispersed particles of the polymer emulsion, the minimum film forming temperature of the polymer emulsion is preferably 30 ° C. or lower. Here, the minimum film-forming temperature refers to a temperature at which a transparent continuous film is formed when a polymer emulsion is cast thinly on a metal plate such as aluminum and the temperature is raised. According to this aspect, it is possible to improve the quick drying property, finger touch property, abrasion resistance, and water resistance of the printed matter.
[0025]
According to a preferred embodiment of the present invention, the polymer fine particles are preferably composed of a thermoplastic polymer as a component. The polymer may be cross-linked. Examples of thermoplastic polymers include ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, polyethylene, polypropylene, polystyrene, poly (meth) acrylate ester, (meth) acrylic acid-styrene copolymer, (Meth) acrylic acid ester- (meth) acrylic acid copolymer, styrene-maleic acid copolymer, styrene-itaconic acid ester copolymer, polyvinyl acetate, polyester, polyurethane, and polyamide. It is not limited.
[0026]
According to the first preferred embodiment of the present invention, the polymer fine particles are made of a polymer containing an ultraviolet absorber and / or a light stabilizer.
[0027]
According to the second preferred embodiment of the present invention, the polymer fine particles are made of a polymer having a site having a UV absorbing ability and / or a light stabilizing ability in the structure.
As described above, since many of the ultraviolet absorbers and light stabilizers are oil-soluble, it is difficult to make them present in a sufficient amount in the water-soluble ink composition. However, according to the present invention, it is possible to obtain a water-soluble ink composition that can provide sufficient light fastness to the printed image. Further, in any of the first and second aspects, the amount of the site having the ultraviolet absorbing ability and / or the light stabilizing ability in the polymer fine particles and the presence of the ultraviolet absorbent and / or the light stabilizing agent are present. Since the amount can be basically set arbitrarily, it is possible to obtain an advantage that the ultraviolet absorption ability and / or light stabilization ability can be set arbitrarily.
[0028]
In the present invention, the ultraviolet absorbing ability and the ultraviolet absorbing agent, and the light stabilizing ability and the light stabilizing agent follow the definitions understood in the art. In other words, due to its mechanism of action, UV absorbing ability and UV absorbers are generally stabilized by releasing the strong energies of UV rays by gradually converting them into thermal energy through keto-enol tautomerism. On the other hand, light stabilizing ability and light stabilizer mean those that are stabilized by radical scavenging, hydroperoxide decomposition, heavy metal scavenging, singlet oxygen quenching. In the present invention, either of them may be present, but according to a preferred embodiment of the present invention, it is preferable that both of them are present.
[0029]
2-1.Polymer fine particles of the first aspect
The polymer fine particles according to the first aspect of the present invention are obtained by physically mixing an ultraviolet absorber and / or a light stabilizer with a polymer component described later.
[0030]
Examples of ultraviolet absorbers and light stabilizers that can be used in the present invention include benzophenone ultraviolet absorbers, benzotriazole ultraviolet absorbers, hindered phenol ultraviolet absorbers, salicylate ultraviolet absorbers, and cyanoacrylate ultraviolet absorbers. And those selected from the group consisting of nickel complex ultraviolet absorbers and hindered amine light stabilizers.
[0031]
More specifically, examples of the benzophenone ultraviolet absorber include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, and 2,2 ', 4,4'-tetrahydroxybenzophenone.
[0032]
Moreover, as a benzotriazole type ultraviolet absorber, 2 (2'-hydroxy-5'-methylphenyl) benzotriazole, 2 (2'-hydroxy-4'-octoxyphenyl) benzotriazole, 2 (2'-hydroxy) -3'-tert-butyl-5'-methylphenyl) 5-chlorobenzotriazole.
[0033]
Furthermore, examples of the salicylate ultraviolet absorber include phenyl salicylate, p-tert-butylphenyl salicylate, and p-octylphenyl salicylate.
[0034]
Examples of cyanoacrylate ultraviolet absorbers include ethyl-2-cyano-3,3′-diphenyl acrylate, methyl-2-cyano-3-methyl-3- (p-methoxyphenyl) acrylate, and butyl-2-cyano. Examples include -3-methyl-3- (p-methoxyphenyl) acrylate.
[0035]
Furthermore, nickel complex salt ultraviolet absorbers include nickel bis (octylphenyl) sulfide, 2,2′-thiobis (4-tert-octylferrate) -n-butylamine nickel (II), 2-2′-thiobis ( 4-tert-octyl ferrate) -2-ethylhexylamine nickel (II), 2-2'-thiobis (4-tert-octyl ferrate) triethanolamine nickel (II).
[0036]
The hindered amine light stabilizer has a 2,2,6,6, -tetramethylpiperidine skeleton and is 2,2,6,6, -tetramethylpiperidine-1-oxyl (triacetone-amine). -N-oxyl).
[0037]
Moreover, it is also possible to use what is marketed as these ultraviolet absorbers or light stabilizers. Specific examples thereof include the following.
[0038]
First, as a benzophenone UV absorber,
2,4-dihydroxybenzophenone (SEESORB 100 (Sibro Kasei), Biosorb 100 (Joint), KEMISORB 10 (Kemipro Kasei), ASL 23 (Shonan Chemical), UVINUL 400 (BASF), Inhibitor DHBP (Eastman Kodak)),
2-Hydroxy-4-methoxybenzophenone (Sumisorb 110 (Sumitomo), SEESORB 101 (Sibro Kasei), Biosorb 110 (Joint), KEMISORB 11 (Kemipro Kasei), ASL 24 (Shonan Chemical), UVINUL M-40 (BASF) , Siasorb UV 9 (ACC), Tomissorb 300 (Yoshitomi)),
2-hydroxy-4-methoxybenzophenone-5-sulfonic acid (SEESORB 101 S (Sibro Kasei), KEMISORB 11 S (Chemipro Kasei), ASL 24 S, 24 ST (Shonan Chemical Industry), UVINUL MS-40 (BASF), Siasorb UV 284 (ACC), Harisorb 101S (Yoshitomi)),
2-Hydroxy-4-n-octoxybenzophenone (Adeka Stub 1413 (Asahi Denka), Sumisorb 130 (Sumitomo), SESORB 102 (Sibro Kasei), KEMISORB 12 (Kemipro Kasei), Biosorb 530 (joint), Siasorb UV 531 (ACC) ), Tomissorb 800 (Yoshitomi), Harisorb 108 (Harima)),
2-hydroxy-4-n-dodecyloxybenzophenone (Inhibitor DHBP (Eastman Kodak), SESORB 103 (Sibro Kasei), KEMISORB 13 (Chemipro Kasei), UV-ehek Ald-320 (Fero)),
Bis (5-benzoyl-4-hydroxy-2-methoxyphenyl) methane (ADK STAB LA-51 (Asahi Denka)),
2,2'-dihydroxy-4-methoxy benzophenone (KEMISORB 111 (Chemipro Kasei), Siasorb UV 24 (ACC)),
2,2'-dihydroxy-4,4'-dimethoxybenzophenone (UVINUL D-49 (BASF)).
[0039]
In addition, as a benzotriazole ultraviolet absorber,
2- (2′-hydroxy-5′-methylphenyl) benzotriazole (Adekastab LA-32 (Asahi Denka), Sumisorb 200 (Sumitomo), SESORB 701 (Sibro Kasei), TINUVIN P (Ciba Geigy), KEMISORB 71 ( Chemipro Kasei), Biosorb 520 (joint), JF-77 (Johoku)),
2- [2′-hydroxy-3 ′, 5′-bis (α, α-dimethylbenzyl) phenyl] benzotriazole (TINUVIN 234 (Ciba Geigy)),
2- (2'-Hydroxy-3 ', 5'-di-t-butyl-phenyl) benzotriazole (Adekastab LA-38 (Asahi Denka), Sumisorb 320 (Sumitomo), SEESORB 705 (Sibro Kasei), TINUVIN 320 ( Ciba Geigy), Biosorb 582 (joint)),
2- (2′-hydroxy-3-t-butyl-5′-methylphenyl) -5-chlorobenzotrizole (Adekastab LA-36 (Asahi Denka), Sumisorb 300 (Sumitomo), SEESORB 703 (Sibro Kasei), TINUVIN326 (Ciba Geigy), Biosorb (joint), Tomissorb (Yoshitomi), JF-600 (Johoku)),
2- (2'-hydroxy-3 ', 5'-di-t-butylphenyl) -5-chlorobenzotriazole (ADK STAB LA-34 (Asahi Denka), SEESORB 702 (Sibro Kasei), TINUVIN 327 (Ciba Geigy) , KEMISORB 72 (Kemipro Kasei), Biosorb 580 (joint)),
2- (2'-hydroxy-3 ', 5'-di-t-amyl) -benzotriazole (Sumisorb 350 (Sumitomo), SEESORB 704 (Sibro Kasei), TINUVIN 328 (Ciba-Geigy)), Biosorb 591 (joint) ),
2- (2'-hydroxy-5'-t-octylphenyl) benzotriazole (Sumisorb 340 (Sumitomo), SEESORB 709 (Sibro Kasei), Biosorb 583 (Joint)), JF-83 (Johoku), Cyasorb UV5411 (ACC) ),
2,2'-methylene bis [4- (1,1,3,3-tetramethylbutyl) -6- (2N-benzotriazol-2-yl) phenol] (ADK STAB LA-31 (Asahi Denka)) It is done.
[0040]
As a salicylate UV absorber,
Phenyl salicylate (SEESORB 201 (Sibro Kasei), Salol P (Iwaki), KEMISORB 21 (Kemipro Kasei)),
4-t-butylphenyl salicylate (SEESORB 202 (Sibro Kasei), Butisalol (Iwaki), KEMISORB 28 (Chemipro Kasei) DIC TBS (Japan))).
[0041]
As a cyanoacrylate UV absorber,
Ethyl-2-cyano-3,3′-diphenyl acrylate (SEESORB 501 (Sibro Kasei), Biosorb 910 (joint), Ushio Sator 300 (Daiichi Kasei Kogyo), UVINUL N-589 (BASF)),
2-ethylhexyl-2-cyano-3,3'-diphenyl acrylate (UVINUL N-589 (BASF)).
[0042]
Moreover, high molecular weight UV absorbers are commercially available. For example, MARK LA-51 and MARK LA-31 manufactured by Asahi Denka, SEESORB 706 manufactured by Sipro Kasei, and UVA 101 manufactured by Takemoto Yushi are available. is there.
[0043]
In addition, as a hindered amine light stabilizer,
Bis- [2,2,6,6-tetramethyl-4-piperidinyl] sebacate (Sanol LS-770 (Sankyo), Adekastab LA-77 (Asahi Denka)),
Bis- [N-methyl-2,2,6,6-tetramethyl-4-piperidinyl] sebacate (Tinuvin 765 (Ciba Geigy), SANOL LS 765 (Sankyo)),
Bis- (1,2,2,6,6-pentamethyl-4-piperidinyl) -2- (3,5-di-tetra-butyl-4-hydroxybenzyl) -2-n-butylmalonate (TINUVIN 144 ( Ciba Geigy)),
Tetrakis (2,2,6,6-tetramethyl-4-piperidyl) -1,2,3,4-butane tetracarboxylate (Adekastab LA-57 (Asahi Denka)),
Tetrakis (1,2,2,6,6-pentamethyl-4-piperidyl) -1,2,3,4-butane tetracarboxylate (ADK STAB LA-52 (Asahi Denka)),
2,2,6,6-tetramethyl-4-piperidyl / tridecyl) -1,2,3,4-butane tetracarboxylate (Adekastab LA-67 (Asahi Denka)
1,2,2,6,6-pentamethyl-4-piperidyl / tridecyl) -1,2,3,4-butane tetracarboxylate (Adekastab LA-62 (Asahi Denka)).
[0044]
Further, according to a preferred embodiment of the present invention, it is preferable to further add a phosphorus-based antioxidant in addition to these ultraviolet absorbers and / or light stabilizers. The addition of the phosphorus-based antioxidant suppresses the discoloration of the polymer and the discoloration of the additive, so that there is an advantage that the color change of the ink composition and the image is suppressed.
[0045]
The production of the polymer fine particles according to the first aspect of the present invention can be preferably carried out as follows. That is, (1) a polymerization reaction is carried out by adding an ultraviolet absorber and / or a light stabilizer to a system comprising a monomer as a reactive species and a polymerization catalyst, and the resulting polymer is dissolved in an organic solvent and stirred. A solution emulsification method in which water is added to the polymer solution to emulsify, (2) without using a solvent, the polymer and the emulsifier obtained in the same manner as described above are melted or kneaded with a kneading mixer or the like. It can be obtained by a method of adding little by little, or (3) a direct emulsification method in which a melted polymer is gradually added to a heated emulsifier aqueous solution while stirring to emulsify. According to another aspect, (4) the polymer fine particles are obtained by emulsifying the resulting polyurethane by reacting a polyol with diisocyanate or polyisocyanate in the presence of an ultraviolet absorber and / or a light stabilizer and a catalyst. It is also possible to obtain it.
[0046]
According to another aspect, the polymer fine particles used in the present invention can be obtained by known emulsion polymerization. Specifically, an ultraviolet absorber and / or a light stabilizer can be dissolved in a monomer, and this monomer component can be obtained by emulsion polymerization in water in the presence of another monomer component, a polymerization catalyst, and an emulsifier. it can. Here, examples of emulsifiers that can be used include anionic surfactants, nonionic surfactants, and mixtures thereof. Examples of anionic activators include alkyl sulfonates, alkyl sulfone sulfates, alkyl benzene sulfonates, alkyl naphthalene sulfonates, alkyl benzene sulfone sulfates, dialkyl sulfosuccinates, fatty acid salts, polyoxyethylene alkyl ether sulfates, polyoxy And ethylene phenyl ether sulfate. Nonionic surfactants are polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene polystyryl phenyl ether, polyoxyethylene-polyoxypropylene glycol, polyoxyethylene-polyoxypropylene alkyl ether, polyoxyethylene fatty acid Examples include esters and polyglycerol fatty acid esters. This emulsion polymerization is a preferred method for producing polymer fine particles in the form of a polymer emulsion. According to a preferred embodiment of the present invention, it is preferable to use a surfactant having an HLB of 15 to 20 from the viewpoint of obtaining a stable polymer emulsion.
[0047]
The monomer component used in the above production method is not particularly limited as long as it provides the polymer component of the polymer fine particles described above, and specific examples thereof include methyl (meth) acrylate, ethyl (meth) acrylate, isopropyl (meta) ) Acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, n-amyl (meth) acrylate, isoamyl (meth) acrylate, n-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, octyl (meta) ) Acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate, octadecyl (meth) acrylate, cyclohexyl (meth) acrylate, phenyl (meth) acrylate, benzyl (meth) acrylate, 2-hydroxyl (meth) a Relate, acrylic acid ester such as hydroxypropyl (meth) acrylate, glycidyl methacrylate, glycidyl acrylate, or vinyl esters such as methacrylic acid ester and vinyl acetate; acrylonitrile, methacrylonitrile, styrene, 2-methylstyrene, vinyltoluene, t -Aromatic vinyls such as butylstyrene, chlorostyrene, vinylanisole, vinylnaphthalene and divinylbenzene; vinylidene halides such as vinylidene chloride and vinylidene fluoride; ethylene, propylene, isopropylenebutadiene, vinylpyrrolidone, vinyl chloride, vinyl ether , Vinyl ketone, chloroprene, etc. and acrylic acid, methacrylic acid, maleic acid or its monoalkyl ester, itaconic acid containing carboxyl group Is an ethylenically unsaturated carboxylic acid such as its monoalkyl ester, fumaric acid or its monoalkyl ester; acrylamide having an amide group, N, N-dimethylacrylamide, etc., N-methylaminoethyl methacrylate containing amino group, N-methyl Alkylamino esters of acrylic acid or methacrylic acid such as aminoethyl acrylate, dimethylaminoethyl methacrylate, dimethylaminoethyl acrylate, diethylaminoethyl methacrylate, diethylaminoethyl methacrylate; N- (2-dimethylaminoethyl) acrylamide, N- (2- Dimethylaminoethyl) methacrylamide, N, N-dimethylaminopropylacrylamide, and other unsaturated amides having an alkylamino group, and vinyl pyridine Vinyl ethers having an alkylamino group such as novinylpyridines, dimethylaminoethyl vinyl ether; vinyl imidazole, vinyl sulfonic acid, styrene sulfonic acid and its salt, 2-acryloylamino-2-methylpropane sulfonic acid, and its salt, etc. And those having a sulfone group. These monomers can be used alone or in admixture of two or more.
[0048]
As described above, the polymer fine particles can have a single particle structure or a core-shell structure, and any structure can be adopted even in the polymer fine particles of the first aspect.
[0049]
Here, the polymer fine particles having a core-shell structure are not particularly limited, but can be produced by a known technique, generally by multi-stage emulsion polymerization.
[0050]
When the polymer fine particles have a core-shell structure, the ultraviolet absorber and / or the light stabilizer may be present in either the core portion or the shell layer, or may be present in both.
[0051]
Furthermore, according to a preferred embodiment of the present invention, it is preferred that the polymer fine particles of the first embodiment have a functional group of either a carboxyl group or a sulfonic acid group in both the single particle structure and the core-shell structure, Those having an amide group, a hydroxyl group or an amino group are preferred. In the case of the core-shell structure, these functional groups are preferably present in the shell layer. These groups may be present in the monomer structure in the production method described above, or may be added to the surface of the polymer fine particles by graft polymerization or the like. The presence of such a group is considered preferable from the following expected mechanism, but the following theory is merely an assumption and the present invention is not limited to this. Hydroxyl groups such as carboxyl groups, sulfonic acid groups, amide groups, amino groups and hydroxyl groups on the surface of such polymer particles are hydrogen-bonded to the hydroxyl groups (OH groups) of cellulose constituting the paper fiber, so that the polymer fine particles and the paper Adsorbs fibers firmly. As a result, the penetration of a color material such as a pigment into the paper is suppressed. In particular, when the polymer fine particle structure is a core-shell structure and the shell layer contains a hydrophilic group such as a carboxyl group, a sulfonic acid group, an amide group, an amino group or a hydroxyl group, these hydrophilic groups on the surface of the fine particle Since the ratio of the presence of increases, further effects can be obtained. The water and water-soluble organic solvent in the vicinity of the polymer fine particles adsorbed on the paper fibers penetrate and decrease inside the paper, so the polymer fine particles are united with each other, and further fused to incorporate a coloring material such as a pigment. Is formed. Further, the ink composition containing the polymer fine particles having these groups does not wet the surface of the nozzle plate subjected to the water repellent treatment of the recording head of the ink jet printer. As a result, there is no discharge failure due to the wetness of the ink nozzle plate surface, and there is no occurrence of flight bending, and the discharge stability is excellent. Furthermore, an ink composition containing polymer fine particles having these groups is excellent in storage stability.
[0052]
2-2.Polymer fine particles of the second aspect
The polymer fine particles according to the second aspect of the present invention are composed of a polymer having a site having an ultraviolet absorbing ability and / or a light stabilizing ability in the polymer structure described later. Examples of the site having an ultraviolet absorbing ability that can be used in this embodiment include a benzophenone skeleton, a benzotriazole skeleton, a hindered phenol skeleton, a salicylate skeleton, and a cyanoacrylate skeleton, and the part having a light stabilizing ability is a hindered amine skeleton. Is mentioned.
[0053]
If we show the specific structure of these skeletons,
Benzophenone skeleton:
[0054]
[Chemical 1]

Benzotriazole skeleton:
[0055]
[Chemical 2]

Hindered phenol skeleton:
[0056]
[Chemical 3]

Salicylate skeleton:
[0057]
[Formula 4]

Cyanoacrylate skeleton:
[0058]
[Chemical formula 5]

And hindered amine skeleton:
[0059]
[Chemical 6]

It is.
[0060]
The introduction of a site having an ultraviolet absorbing ability and / or a light stabilizing ability into the polymer structure can be carried out by copolymerizing a copolymerizable monomer having the skeleton in the molecular structure with another monomer. it can.
[0061]
In the present invention, specific examples of the monomer having a portion having an ultraviolet absorbing ability and / or a light stabilizing ability include the above-described portion having an ultraviolet absorbing ability and / or a light stabilizing ability, a methacryloyl group, an acroyl group, and a vinyl group. And having an ethylenically unsaturated group such as an allyl group.
[0062]
Specific examples of such monomers include the following. First, specific examples of the monomer having an ultraviolet absorption site having a benzophenone skeleton include the following.
[0063]
[Chemical 7]

[0064]
[Chemical 8]

Specific examples of the monomer having an ultraviolet absorption site having a benzotriazole skeleton include the following.
[0065]
[Chemical 9]

[0066]
[Chemical Formula 10]

[0067]
Embedded image

Further, specific examples of the monomer having an ultraviolet absorbing site having a hindered phenol skeleton include the following.
[0068]
Embedded image

Moreover, the following are mentioned as a specific example of the monomer which has a photostable site | part which has a hindered amine skeleton.
[0069]
Embedded image

[0070]
Embedded image

It is also possible to use a commercially available monomer having a portion having an ultraviolet absorbing ability and / or a light stabilizing ability. Examples of commercially available products include a monomer having an ultraviolet absorbing portion having a benzotriazole skeleton. As RUVA-93 (2- (2′-hydroxy-5-methylacryloxyethylphenyl) -2H-benzotriazole) available from Otsuka Chemical Co., Ltd. Further, as a monomer having a light stabilizing site having a hindered amine skeleton, ADK STAB LA-82 (1,2,2,6,6-pentamethyl-4-piperidyl methacrylate) available from Asahi Denka Kogyo Co., Ltd., LA-87 (2,2,6,6-tetramethyl-4-piperidyl methacrylate).
[0071]
The fine polymer particles according to the second aspect are produced by polymerizing by a polymerization method appropriately selected in consideration of the monomer having a portion having ultraviolet absorbing ability and / or light stabilizing ability and the type of other monomer. Can do.
[0072]
According to a preferred embodiment of the present invention, the polymer fine particles of the second embodiment used in the present invention can be obtained by known emulsion polymerization. Specifically, it is obtained by emulsion polymerization of a monomer component constituting the polymer and a monomer having a site having an ultraviolet absorbing ability and / or a light stabilizing ability in water in the presence of a polymerization catalyst and an emulsifier. Can do.
[0073]
Specific examples of the monomer component constituting the polymer that can be used in the second aspect include those similar to the monomer component constituting the polymer fine particle of the first aspect. Moreover, the same thing as what was demonstrated in said 1st aspect is mentioned also about the specific example of the emulsifier used in said emulsion polymerization.
[0074]
The fine polymer particles of the second aspect may also be in the form of a polymer emulsion, and can be preferably produced by the above emulsion polymerization. Commercially available products can also be used as the polymer fine particles of the second embodiment in the form of a polymer emulsion. Examples thereof include UVA-383MA and UVA-383MG manufactured by BASF.
[0075]
As described above, the polymer fine particles can have a single particle structure or a core-shell structure, and any structure can be adopted even in the polymer fine particles of the second aspect.
[0076]
Here, the polymer fine particles of the second aspect having a core-shell structure can be similarly produced by the method described in the first aspect.
[0077]
In addition, when the polymer fine particles have a core-shell structure, the polymer having ultraviolet absorption ability and / or light stabilization ability may constitute either the core portion or the shell layer, or both. Good.
[0078]
Further, similarly to the polymer fine particles according to the first aspect, the polymer fine particles according to the second aspect preferably have either a carboxyl group or a sulfonic acid group, and further have an amide group. And those having a hydroxyl group or an amino group are preferred. Further, when the polymer fine particles according to the second embodiment have a core-shell structure, it is preferable that these functional groups exist in the shell layer.
[0079]
3.Color material
The color material contained in the ink composition according to the present invention may be either a dye or a pigment, but is preferably a pigment.
[0080]
As the dye, various dyes such as a direct dye, an acid dye, an edible dye, a basic dye, a reactive dye, a disperse dye, a vat dye, a soluble vat dye, and a reactive disperse dye can be used.
[0081]
Moreover, as a pigment, an inorganic pigment and an organic pigment can be used. As the inorganic pigment, in addition to titanium oxide and iron oxide, carbon black produced by a known method such as a contact method, a furnace method, or a thermal method can be used. Organic pigments include azo pigments (including azo lakes, insoluble azo pigments, condensed azo pigments, chelate azo pigments), polycyclic pigments (for example, phthalocyanine pigments, perylene pigments, perinone pigments, anthraquinone pigments, quinacridone pigments, dioxazines). Pigments, thioindigo pigments, isoindolinone pigments, quinofullerone pigments, etc.), dye chelates (for example, basic dye chelate, acid dye chelate, etc.), nitro pigments, nitroso pigments, aniline black, and the like.
In particular, carbon black used as black ink includes No.2300, No.900, MCF88, No.33, No.40, No.45, No.52, MA7, MA8, MA100, No2200B manufactured by Mitsubishi Chemical, etc. Are Raven5750, Raven5250, Raven5000, Raven3500, Raven1255, Raven700, etc., manufactured by Colombia, etc. , Monarch 1100, Monarch 1300, Monarch 1400, etc. are Degussa Color Black FW1, Color Black FW2, Color Black FW2V, Color Black FW18, Color Black FW200, Color Black S150, Color Black S160, Color Black S170, Printex 35 , Printex U, Printex V, Printex 140U, Special Black 6, Special Black 5, Special Black 4A, Special Black 4, etc. can be used. Examples of pigments used in yellow ink include CIPigment Yellow 1, CIPigment Yellow 2, CIPigment Yellow 3, CIPigment Yellow 12, CIPigment Yellow 13, CIPigment Yellow 14C, CIPigment Yellow 16, CIPigment Yellow 17, CIPigment Yellow 73, CIPigment Yellow 74, CIPigment Yellow 75, CIPigment Yellow 83, CIPigment Yellow 93, CIPigment Yellow 95, CIPigment Yellow 97, CIPigment Yellow 98, CIPigment Yellow 114, CIPigment Yellow128, CIPigment Yellow129, CIPigment Yellow151, CIPigment Yellow154 etc. are mentioned. The pigments used in magenta ink include CIPigment Red 5, CIPigment Red 7, CIPigment Red 12, CIPigment Red 48 (Ca), CIPigment Red 48 (Mn), CIPigment Red 57 (Ca) , CIPigment Red 57: 1, CIPigment Red 112, CIPigment Red 123, CIPigment Red 168, CIPigment Red 184, CIPigment Red 202, and the like. CIPigment Blue 1, CIPigment Blue 2, CIPigment Blue 3, CIPigment Blue 15: 3, CIPigment Blue 15:34, CIPigment Blue 16, CIPigment Blue 22, CI Pigment Blue 60, CIVat Blue 4, CIVat Blue 60 etc. are mentioned. However, it is not limited to these.
[0082]
The particle diameter of these pigments is preferably 10 μm or less, more preferably 0.1 μm or less.
[0083]
According to a preferred embodiment of the present invention, these pigments are preferably added to the ink as a pigment dispersion obtained by dispersing the pigment in an aqueous medium with a dispersant or a surfactant. As a preferable dispersant, a dispersant conventionally used for preparing a pigment dispersion, for example, a polymer dispersant can be used. It will be apparent to those skilled in the art that the dispersant and surfactant contained in the pigment dispersion will also function as the dispersant and surfactant of the ink composition. Preferable examples of the polymer dispersant include natural polymers. Specific examples thereof include proteins such as glue, gelatin, casein, and albumin, natural rubbers such as gum arabic and tragacanth, glucosides such as saponin, Examples include alginic acid and propylene glycol alginate, alginic acid derivatives such as triethanolamine alginate and ammonium alginate, and cellulose derivatives such as methylcellulose, carboxymethylcellulose, hydroxyethylcellulose, and ethylhydroxycellulose. Furthermore, preferred examples of the polymer dispersant include synthetic polymers such as polyvinyl alcohols, polyvinylpyrrolidones, polyacrylic acid, acrylic acid-acrylonitrile copolymer, potassium acrylate-acrylonitrile copolymer, vinyl acetate. -Acrylic resin such as acrylic acid ester copolymer, acrylic acid-acrylic acid ester copolymer, styrene-acrylic acid copolymer, styrene-methacrylic acid copolymer, styrene-methacrylic acid-acrylic acid ester copolymer Styrene-acrylic resins such as styrene-α-methylstyrene-acrylic acid copolymer, styrene-α-methylstyrene-acrylic acid-acrylic acid ester copolymer, styrene-maleic acid copolymer, styrene-maleic anhydride Copolymer, vinyl naphthalene-acrylic acid copolymer , Vinyl naphthalene-maleic acid copolymer, vinyl acetate-ethylene copolymer, vinyl acetate-fatty acid vinyl ethylene copolymer, vinyl acetate-maleic acid ester copolymer, vinyl acetate-crotonic acid copolymer, acetic acid Examples thereof include vinyl acetate copolymers such as vinyl-acrylic acid copolymers and salts thereof. Among these, a copolymer of a monomer having a hydrophobic group and a monomer having a hydrophilic group, and a polymer comprising a monomer having both a hydrophobic group and a hydrophilic group in the molecular structure are particularly preferable.
[0084]
The pigment content in the ink composition of the present invention is preferably about 0.5 to 25% by weight, more preferably about 2 to 15% by weight.
[0085]
4).Water-soluble organic solvent
The ink composition according to the present invention comprises a water-soluble organic solvent. This water-soluble organic solvent is preferably a low-boiling organic solvent, and examples thereof include methanol, ethanol, n-propyl alcohol, iso-propyl alcohol, n-butanol, sec-butanol, tert-butanol, and iso-butanol. , N-pentanol and the like. A monohydric alcohol is particularly preferable. The low boiling point organic solvent has an effect of shortening the drying time of the ink. The amount of the low-boiling organic solvent added is preferably 0.1 to 30% by weight of the ink, more preferably 5 to 10% by weight.
[0086]
According to a preferred aspect of the present invention, the ink composition used in the present invention preferably further comprises a wetting agent composed of a high-boiling organic solvent. Preferred examples of the high boiling point organic solvent agent include ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, polypropylene glycol, propylene glycol, butylene glycol, 1,2,6-hexanetriol, thioglycol, hexylene glycol, glycerin, Polyhydric alcohols such as trimethylolethane and trimethylolpropane, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl Ether, triethylene glycol monobutyl ether Alkyl ethers of polyhydric alcohols such as urea, 2-pyrrolidone, N- methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone and the like.
[0087]
The amount of these wetting agents added is preferably 0.1 to 30% by weight of the ink, more preferably 1 to 10% by weight.
[0088]
According to a preferred embodiment of the present invention, when the glass transition point of the polymer fine particles is 30 ° C. or lower or the minimum film forming temperature of the polymer emulsion is 30 ° C. or lower, it is preferable to use a water-soluble organic solvent having a boiling point of 180 ° C. or higher. Preferred examples of the water-soluble organic solvent include ethylene glycol (boiling point: 197 ° C .; the parentheses indicate the boiling point below), propylene glycol (187 ° C.), diethylene glycol (245 ° C.), pentamethylene glycol (242 ° C.), Methylene glycol (214 ° C), 2-butene-1,4-diol (235 ° C), 2-ethyl-1,3-hexanediol (243 ° C), 2-methyl-2,4-pentanediol (197 ° C) N-methyl-2-pyrrolidone (202 ° C.), 1,3-dimethyl-2-imidazolidinone (257-260 ° C.), 2-pyrrolidone (245 ° C.), glycerin (290 ° C.), tripropylene glycol monomethyl ether (243 ° C), dipropylene glycol monoethyl glycol (198 ° C), dipropylene glycol Monomethyl ether (190 ° C), dipropylene glycol (232 ° C), triethylene glycol monomethyl ether (249 ° C), tetraethylene glycol (327 ° C), triethylene glycol (288 ° C), diethylene glycol monobutyl ether (230 ° C) ), Diethylene glycol monoethyl ether (202 ° C.), diethylene glycol monomethyl ether (194 ° C.) and the like. According to a preferred embodiment of the present invention, examples of the high-boiling water-soluble solvent include ethylene glycol, diethylene glycol, pentamethylene glycol, trimethylene glycol, 2-butene-1,4-diol, 2-ethyl-1,3-hexane. Diol, 2-methyl-2,4-pentanediol, glycerin, dipropylene glycol, tetraethylene glycol, triethylene glycol, N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, and 2- Preference is given to using those selected from pyrrolidone.
[0089]
Furthermore, according to a preferred aspect of the present invention, the ink composition according to the present invention preferably contains a sugar, a tertiary amine, an alkali hydroxide, or ammonia. With these additions, the color material does not aggregate or increase in viscosity even during long-term storage, and is excellent in storage stability. In addition, it is fluid and reusable even when left in an open state (in a state where it is exposed to air at room temperature). An ink composition that maintains the dispersibility for a long time and has high ejection stability without clogging of the nozzles during restarting after printing or after interruption of printing can be obtained.
[0090]
Examples of sugars that can be added to the ink composition according to the present invention include monosaccharides, disaccharides, oligosaccharides (including trisaccharides and tetrasaccharides), and polysaccharides, preferably glucose, mannose, fructose, ribose, and xylose. Arabinose, galactose, aldonic acid, glucitol, (sorbit), maltose, cellobiose, lactose, sucrose, trehalose, maltotriose, and the like. Here, the polysaccharide means a saccharide in a broad sense, and is used to include a substance that exists widely in nature, such as alginic acid, α-cyclodextrin, and cellulose. In addition, derivatives of these saccharides include reducing sugars of the aforementioned saccharides (for example, sugar alcohol (general formula HOCH₂(CHOH) nCH₂OH (wherein n represents an integer of 2 to 5), oxidized sugar (eg, aldonic acid, uronic acid, etc.), amino acid, thiosugar and the like. Particularly preferred are sugar alcohols, and specific examples include maltitol and sorbit.
[0091]
The content of these saccharides is in the range of 0.1 to 40% by weight, more preferably 1 to 30% by weight of the ink.
[0092]
Examples of the tertiary amine that can be added to the ink composition according to the present invention include trimethylamine, triethylamine, triethanolamine, dimethylethanolamine, diethylethanolamine, triisopropenolamine, and butyldiethanolamine. These may be used alone or in combination. The amount of these tertiary amines added to the ink composition of the present invention is 0.1 to 10% by weight, more preferably 0.5 to 5% by weight.
[0093]
The alkali hydroxide that can be added to the ink composition according to the present invention is potassium hydroxide, sodium hydroxide, or lithium hydroxide, and the amount added to the ink composition of the present invention is 0.01 to 5% by weight. And preferably 0.05 to 3% by weight.
[0094]
The ink composition of the present invention can further contain a surfactant. Examples of surfactants include anionic surfactants (eg, sodium dodecyl benzene sulfonate, sodium laurate, ammonium salts of polyoxyethylene alkyl ether sulfates), nonionic surfactants (eg, polyoxyethylene Alkyl ethers, polyoxyethylene alkyl esters, polyoxyethylene sorbitan fatty acid esters, polyoxyethylene alkyl phenyl ethers, polyoxyethylene alkyl amines, polyoxyethylene alkyl amides, etc.) and acetylene glycols (olefin Y and surfinol 82, 104) 440, 465, and 485 (all manufactured by Air Products and Chemicals Inc.), which can be used alone or in combination of two or more.
[0095]
The ink composition of the present invention may contain general-purpose polymer fine particles in addition to the polymer fine particles. The general-purpose polymer fine particles are preferably used in the form of a polymer emulsion. Examples of the polymer fine particles include acrylic polymers, vinyl acetate polymers, styrene-butadiene copolymers, vinyl chloride polymers, acrylic-styrene copolymers, butadiene polymers, and styrene polymers. Further, the particle diameter of these polymer fine particles is preferably about 200 nm or less, more preferably about 5 to 200 nm. These polymer fine particles may be those commercially available in the form of a polymer emulsion. For example, microgel E-1002, E-5002 (styrene-acrylic polymer emulsion, manufactured by Nippon Paint Co., Ltd.), Boncoat 4001 (acrylic polymer emulsion, manufactured by Dainippon Ink & Chemicals, Inc.) Boncoat 5454 (styrene-acrylic polymer emulsion, manufactured by Dainippon Ink & Chemicals, Inc.), SAE-1014 (styrene-acrylic polymer emulsion, manufactured by Nippon Zeon Co., Ltd.) Company-made), Cybinol SK-200 (acrylic polymer emulsion, made by Seiden Chemical Co., Ltd.), and the like.
[0096]
In addition, you may add a pH adjuster, antiseptic | preservative, a fungicide, a phosphorus antioxidant, etc. as needed.
[0097]
The ink composition according to the present invention can be produced by dispersing and mixing the above components by an appropriate method. Preferably, the pigment, polymer dispersant and water are first mixed with a suitable dispersing machine (eg, ball mill, sand mill, attritor, roll mill, agitator mill, Henschel mixer, colloid mill, ultrasonic homogenizer, jet mill, ang mill, etc.) A uniform pigment dispersion, and after sufficiently dissolving in water by adding a water-soluble organic solvent having a boiling point of 180 ° C. or higher, a sugar, a pH adjuster, a preservative, a fungicide, etc. A polymer emulsion having the polymer fine particles as dispersed particles is added and sufficiently stirred at room temperature with an appropriate disperser to prepare an ink solvent. While stirring the pigment dispersion with an appropriate disperser, the ink solvent is gradually dropped and further stirred sufficiently. After sufficiently stirring, filtration is performed to remove coarse particles and foreign matters that cause clogging, thereby obtaining a target ink composition.
[0098]
5.Inkjet recording method
The ink composition according to the present invention is preferably used in the ink jet recording method as described above. Furthermore, the ink composition according to the present invention is preferably used in a color ink jet recording method using a plurality of color ink compositions. This color ink jet recording method will be described with reference to the drawings.
[0099]
The ink jet recording apparatus of FIG. 1 is an aspect in which an ink composition is stored in a tank and the ink composition is supplied to a recording head via an ink tube. That is, the recording head 1 and the ink tank 2 are communicated with each other through the ink tube 3. Here, the interior of the ink tank 2 is partitioned, and a room for an ink composition and, in some cases, a plurality of color ink compositions is provided.
[0100]
The recording head 1 moves along a carriage 4 by a timing belt 6 driven by a motor 5. On the other hand, the paper 7 as a recording medium is placed at a position facing the recording head 1 by a platen 8 and a guide 9. In this embodiment, a cap 10 is provided. A suction pump 11 is connected to the cap 10 to perform a so-called cleaning operation. The sucked ink composition is stored in the waste ink tank 13 through the tube 12.
[0101]
An enlarged view of the nozzle surface of the recording head 1 is shown in FIG. The portion denoted by 1c is the nozzle surface of the ink composition, and the yellow ink composition, magenta ink composition, cyan ink composition, and black ink composition are ejected from the nozzles 22, 23, 24, and 25, respectively. The
[0102]
Further, an ink jet recording method using the recording head shown in FIG. 2 will be described with reference to FIG. The recording head 1 moves in the direction of arrow A. During the movement, the ink composition is printed to form the print area 31.
[0103]
Further, some ink jet recording apparatuses are replenished with an ink composition by replacing a cartridge which is an ink tank. The ink tank may be integrated with the recording head.
[0104]
A preferred example of an ink jet recording apparatus using such an ink tank is shown in FIG. In the figure, the same members as those in the apparatus of FIG. In the embodiment of FIG. 4, the recording head 1 is integrated with the ink tank 2. The printing method may be basically the same as that of the apparatus shown in FIG. In this embodiment, the recording head 1 and the ink tank 2 move together on the carriage 4.
[0105]
6).Recording method using two liquids
Furthermore, according to a preferred aspect of the present invention, the ink composition according to the present invention comprises two liquids: an ink composition and a reaction liquid containing a reactive agent that contacts the ink composition to form an aggregate. It is preferably used in a recording method using According to this method, it is possible to obtain an image having excellent fixability, excellent finger touch, abrasion resistance, and water resistance, and having a good OD value and glossiness. The reason is that the dispersion state of the colorant and the polymer emulsion causes the reactants to collapse and produce aggregates, and has excellent fixability to a recording medium such as paper, high OD value and glossiness, High-quality images without feathering, bleeding, and bleeding are expected to be realized.
[0106]
Examples of reactants that form aggregates upon contact with the ink composition according to the present invention include polyvalent metal salts and / or polyallylamine and / or derivatives thereof.
[0107]
The polyvalent metal salt is composed of a divalent or higher polyvalent metal ion and an anion that binds to the polyvalent metal ion, and is soluble in water. Specific examples of polyvalent metal ions include Ca²⁺, Cu²⁺, Ni²⁺, Mg²⁺, Zn²⁺, Ba²⁺Divalent metal ions such as Al³⁺, Fe³⁺, Cr³⁺And trivalent metal ions. Specific examples of anions include Cl^-, NO_Three ^-, I^-, Br^-, ClO_Three ^-And CH_ThreeCOO^- Nitrate ions or carboxylate ions are preferable. Here, the carboxylate ion is preferably derived from a carboxylic acid selected from the group consisting of a saturated aliphatic monocarboxylic acid having 1 to 6 carbon atoms and a carbocyclic monocarboxylic acid having 7 to 11 carbon atoms. is there. Preferable examples of the saturated aliphatic monocarboxylic acid having 1 to 6 carbon atoms include formic acid, acetic acid, propionic acid, isobutyric acid, valeric acid, isovaleric acid, pivalic acid, hexanoic acid and the like. In particular, formic acid and acetic acid are preferred. The hydrogen atom on the saturated aliphatic hydrocarbon group of the monocarboxylic acid may be substituted with a hydroxyl group. Preferred examples of such carboxylic acid include benzoic acid and naphthoic acid, and more preferred is benzoic acid. It is an acid.
[0108]
Polyallylamine and polyallylamine derivatives are cationic polymers that are soluble in water and positively charged in water. For example, Formula (a), Formula (b), and Formula (c) are mentioned.
[0109]
Embedded image

(Where X^-Represents chloride ion, bromide ion, iodide ion, nitrate ion, phosphate ion, sulfate ion, acetate ion and the like. )
Furthermore, a polymer in which allylamine and diallylamine are copolymerized or a copolymer of diallylmethylammonium chloride and sulfur dioxide can be used.
[0110]
The reaction solution used in the present invention basically comprises a polyvalent metal salt and / or polyallylamine and / or a polyallylamine derivative, and water.
[0111]
The concentration of the polyvalent metal salt in the reaction solution may be appropriately determined as long as the printing quality and the effect of preventing clogging are obtained, but is preferably about 0.1 to 40% by weight of the reaction solution. Preferably, it is about 5 to 25% by weight. The concentration of the polyallylamine and / or polyallylamine derivative in the reaction solution is preferably 0.5 to 10% by weight of the reaction solution. .
[0112]
In the present invention, the reaction solution preferably contains a wetting agent such as a high boiling point organic solvent. Preferable examples of the high boiling point organic solvent include those described in the ink composition section. The high boiling point organic solvent prevents clogging of the head by preventing the reaction solution from drying.
[0113]
The amount of the high-boiling organic solvent added is not particularly limited, but is preferably about 0.5 to 40% by weight, more preferably about 2 to 20% by weight.
[0114]
According to a more preferred embodiment of the present invention, it is preferable to add triethylene glycol monobutyl ether or glycerin as the high boiling point organic solvent. When these are added in combination, the addition amounts of triethylene glycol monobutyl ether and glycerin are preferably about 10 to 20% by weight and about 1 to 15% by weight, respectively. Moreover, you may add the said surfactant to this reaction liquid. In addition, in order to improve the storage stability, a pH adjuster such as ammonia, an antiseptic, an antifungal agent and the like may be added to the reaction solution as necessary.
[0115]
In addition, the reaction liquid may be colored by adding a color coloring material, and may have a function of an ink composition.
[0116]
Regarding the attachment of the reaction liquid to the recording medium, either a method of selectively attaching the reaction liquid only at a place where the ink composition is attached or a method of attaching the reaction liquid to the entire paper may be employed. The former is economical because the consumption of the reaction liquid can be minimized, but a certain degree of accuracy is required at the position where both the reaction liquid and the ink composition are attached. On the other hand, the latter requires less accuracy in the position of attachment of the reaction liquid and the ink composition than the former, but a large amount of the reaction liquid is attached to the entire paper, and the paper is likely to curl during drying. Therefore, which method is adopted may be determined in consideration of the combination of the ink composition and the reaction liquid.
[0117]
According to a preferred aspect of the present invention, the ink composition and the reaction liquid are preferably applied to a recording medium by a so-called ink jet recording method. That is, a recording method in which droplets are ejected from ink ejection holes of an ink jet recording head and adhered to a recording medium to form an image is preferable.
[0118]
The inkjet recording method using the ink composition and the reaction liquid according to the present invention will be further described with reference to the drawings.
[0119]
The ink jet recording apparatus of FIG. 5 is an embodiment in which an ink composition and a reaction liquid are stored in a tank, and the ink composition and the reaction liquid are supplied to a recording head via an ink tube. That is, the recording head 51 and the ink tank 52 are communicated with each other through the ink tube 3. Here, the inside of the ink tank 52 is partitioned, and an ink composition, and in some cases, a plurality of color ink composition rooms and a reaction liquid room are provided.
[0120]
The recording head 51 moves along the carriage 4 by the timing belt 6 driven by the motor 5. On the other hand, the paper 7 as a recording medium is placed at a position facing the recording head 51 by the platen 8 and the guide 9. In this embodiment, a cap 10 is provided. A suction pump 11 is connected to the cap 10 to perform a so-called cleaning operation. The sucked ink composition is stored in the waste ink tank 13 through the tube 12.
[0121]
An enlarged view of the nozzle surface of the recording head 51 is shown in FIG. A portion indicated by 51b is a nozzle surface of the reaction liquid, and a nozzle 21 for discharging the reaction liquid is provided in the vertical direction. On the other hand, the portion indicated by 51c is the nozzle surface of the ink composition, and the yellow ink composition, magenta ink composition, cyan ink composition and black ink composition are respectively supplied from the nozzles 22, 23, 24 and 25. Discharged.
[0122]
Further, an ink jet recording method using the recording head shown in FIG. 6 will be described with reference to FIG. The recording head 51 moves in the direction of arrow A. During the movement, the reaction liquid is discharged from the nozzle surface 51 b to form a belt-like reaction liquid adhesion region 61 on the recording medium 7. Next, the recording medium 7 is transferred to the paper feed direction arrow B by a predetermined amount. Meanwhile, the recording head 51 moves in the direction opposite to the arrow A in the figure and returns to the left end position of the recording medium 7. Then, the ink composition is printed on the reaction liquid adhesion area where the reaction liquid has already adhered, thereby forming the print area 62.
[0123]
Further, as shown in FIG. 8, in the recording head 51, all the nozzles can be arranged in the horizontal direction. In the figure, 41a and 41b are reaction liquid discharge nozzles, and yellow ink composition, magenta ink composition, cyan ink composition, and black ink composition are discharged from nozzles 42, 43, 44, and 45, respectively. The In such a recording head, printing can be performed in both the forward path and the backward path in which the recording head 51 reciprocates on the carriage, and at a higher speed than when the recording head shown in FIG. 7 is used. Printing can be expected.
[0124]
Further, some ink jet recording apparatuses are replenished with an ink composition by replacing a cartridge which is an ink tank. The ink tank may be integrated with the recording head.
[0125]
A preferred example of an ink jet recording apparatus using such an ink tank is shown in FIG. In the figure, the same members as those in the apparatus of FIG. In the embodiment of FIG. 9, the recording heads 51a and 51b are integrated with the ink tanks 52a and 52b. Assume that the recording head 51a or 51b ejects the ink composition and the reaction liquid, respectively. The printing method may be basically the same as that of the apparatus shown in FIG. In this embodiment, the recording head 51a, the ink tank 52a, the recording head 51a, and the ink tank 52b move together on the carriage 4.
[0126]
【Example】
Polymer emulsion 1
A reaction vessel equipped with a stirrer, reflux condenser, dropping device, thermometer and nitrogen introduction tube was charged with 200 ml of distilled water and 0.6 g of sodium dodecylbenzenesulfonate to 70 ° C. with stirring in a nitrogen atmosphere. Warm and add 2 g of potassium persulfate. On the other hand, 40 g of butyl acrylate, 50 g of styrene, 5 g of acrylamide, 5 g of acrylic acid, 0.15 g of t-dodecyl mercaptan, and 1 g of ultraviolet absorber 2 (2′-hydroxy-5′-methylphenyl) benzotriazole (SEESORB 709 manufactured by Cypro Kasei) Are mixed and dissolved, and this is dropped into the reaction vessel. Furthermore, after reacting at 70 ° C. for 6 hours, cooling to room temperature, adding aqueous ammonia as a neutralizing agent to prepare PH, filtering with a 10 μm filter, dispersing polymer fine particles containing an ultraviolet absorber A polymer emulsion is obtained as particles. This polymer emulsion has a glass transition point of 20 ° C. and a minimum film formation temperature of 25 ° C.
[0127]
Polymer emulsion 2
A reaction vessel equipped with a stirrer, reflux condenser, dripping device, thermometer and nitrogen inlet tube was charged with 200 ml of distilled water and 0.6 g of sodium dodecylbenzenesulfonate and heated to 70 ° C. with stirring in a nitrogen atmosphere. Warm and add 2 g of potassium persulfate. On the other hand, 40 g of butyl acrylate, 50 g of styrene, 5 g of acrylamide, 5 g of acrylic acid, 0.1 g of t-dodecyl mercaptan, and monomer 2 (2′-hydroxy-5′-methacryloxyethylphenyl)-having a UV-absorbing skeleton Monomer 1,2,2,6,6-pentamethyl-4-piperidyl methacrylate (Adekastab LA-82, manufactured by Asahi Denka) having 5 g of 2H-benzotriazole (RUVA-93 manufactured by Otsuka Chemical Co., Ltd.) and a skeleton having photostabilization ability 1 g is mixed and dissolved, and this is dropped into the reaction vessel. Furthermore, after reacting at 70 ° C. for 6 hours, the solution is cooled to room temperature, pH is adjusted by adding ammonia water as a neutralizing agent, filtered through a 10 μm filter, and a portion having ultraviolet absorbing ability and light stabilizing ability is obtained. A polymer emulsion having polymer fine particles in the structure as dispersed particles is obtained. This polymer emulsion had a glass transition point of 20 ° C. and a minimum film formation temperature of 25 ° C.
[0128]
Measurement of glass transition point
The film obtained by drying the water of the polymer emulsion is measured with a differential scanning calorimeter (DSC) at a heating rate of 10 ° C./min.
[0129]
Minimum filming temperature measurement
A minimum film forming temperature measuring device is set, and when the temperature gradient on the aluminum sample plate reaches equilibrium, the polymer emulsion of the sample is thinly spread and dried. When the sample plate is observed after drying, a transparent continuous film is formed in a temperature range above the minimum film formation temperature, but becomes a white powder in a temperature range below the minimum film formation temperature. The temperature at this boundary is measured as the minimum film formation temperature.
[0130]

[0131]

[0132]

[0133]
The above ink is prepared as follows.
First, a pigment, a dispersant, and water are mixed and dispersed in a sand mill (manufactured by Yasukawa Seisakusho) with glass beads (diameter 1.7 mm, 1.5 times the weight of the mixture (weight)) for 2 hours, and then glass beads. Is removed to prepare a pigment dispersion. Next, after adding the polymer emulsion 1, glycerin, maltitol, 2-pyrrolidone, triethanolamine and potassium hydroxide to water and stirring for 20 minutes at room temperature, the above pigment dispersion is gradually added dropwise with stirring. Stir for an additional 20 minutes. This is filtered through a 5 μm membrane filter to obtain an ink for ink jet recording.
[0134]

[0135]

[0136]

The above ink was prepared in the same manner as for color ink 1.
[0137]
Color ink 3
For this ink, a commercially available polymer emulsion UVA-383MA manufactured by BASF using polymer fine particles having the above-described site having an ultraviolet absorbing ability in the structure was used. Such polymer fine particles use 2-hydroxy-4- (methacryloyloxyethoxy) benzophenone as a copolymerization component as a monomer having a portion having an ultraviolet absorbing ability, and have a glass transition point of about 27 ° C. and the minimum composition of such a polymer emulsion. The film temperature is 0 ° C. or lower.
[0138]

[0139]

[0140]

The above ink was prepared in the same manner as for color ink 1.
[0141]

[0142]

[0143]

The above ink is prepared in the same manner as the color ink 1.
[0144]

[0145]

[0146]

[0147]
The above ink is prepared in the same manner as the color ink 1.
[0148]
Preparation of reaction solution
(Reaction solution 1)
Magnesium nitrate hexahydrate 25% by weight
Triethylene glycol
Monobutyl ether 10% by weight
Glycerin 20% by weight
Pure water remaining
[0149]
(Reaction solution 2)
5% by weight of polyallylamine represented by the formula (a)
Triethylene glycol
Monobutyl ether 10% by weight
Glycerin 20% by weight
Pure water remaining
[0150]
Evaluation test
Evaluation 1: Light resistance
(Printing method)
Using the inkjet recording apparatus of FIG. 1, printing each of yellow, magenta, and cyan inks of color inks 1 to 5 on plain paper Xerox 4024, Xerox P, and inkjet dedicated paper (manufactured by Seiko Epson Corporation) at 100% duty And a solid image of 3 cm × 3 cm is obtained.
Example 1: Recorded matter obtained using color ink 1 by the above printing method.
Example 2: Recorded matter obtained by using the color ink 2 by the above printing method.
Example 3: Recorded matter obtained using the color ink 3 by the above printing method.
Comparative Example 1: Recorded matter obtained using the color ink 4 by the above printing method.
Comparative Example 2: Recorded matter obtained using the color ink 5 by the above printing method.
Using the ink jet recording apparatus of FIG. 5, the reaction liquid 1 and the yellow, magenta, and cyan inks of the color inks 1 to 5 are added to plain paper Xerox 4024, Xerox P and ink jet exclusive paper (manufactured by Seiko Epson Corporation). Printing is performed with% duty, and a solid image of 3 cm × 3 cm is obtained.
Example 4: Recorded matter obtained by using the reaction liquid 1 and the color ink 1 by the above printing method.
Example 5: Recorded matter obtained by using the reaction liquid 1 and the color ink 2 by the above printing method.
Example 6: Recorded matter obtained by using the reaction liquid 1 and the color ink 3 by the above printing method.
Comparative Example 3: Recorded matter obtained by using the reaction solution 1 and the color ink 4 by the above printing method.
Comparative Example 4: Recorded matter obtained by using the reaction solution 1 and the color ink 5 by the above printing method.
[0151]
Evaluation methods
The solid image recorded by the above method is subjected to an exposure test for 600 hours using a xenon fade meter. The solid image portion before and after exposure was measured with a Macbeth CE-7000 spectrophotometer (manufactured by Macbeth) and indicated by the L * a * b * color difference display method defined by the CIE. The color change before and after exposure is expressed by the color difference obtained by the following equation.
Color difference: ΔE * ab = [(ΔL *)²+ (Δa *)²+ (Δb *)²]^1/2
The value is evaluated according to the following criteria.

Further, the color density before exposure of the solid image portion and the color density after exposure are measured with a Macbeth densitometer TR927 (manufactured by Macbeth), and the change in color density before and after the exposure of the solid image portion is evaluated according to the following criteria.

The evaluation results are as shown in the following table.
[Table 1]

[Table 2]

[0152]
Evaluation 2: Print quality (smear)
Using the inkjet recording apparatus of FIG. 5, printing is performed on each of the following papers using the reaction liquid 1 or 2 and the yellow, magenta, and cyan inks of the color inks 1 to 5. The combinations are as follows.
Example 7: Recorded matter obtained by using the reaction liquid 1 and the color ink 1 by the above printing method.
Example 8: Recorded matter obtained by using the reaction liquid 1 and the color ink 2 by the above printing method.
Example 9: Recorded matter obtained by using the reaction liquid 2 and the color ink 1 by the above printing method.
Example 10: Recorded matter obtained by using the reaction liquid 2 and the color ink 2 by the above printing method.
Comparative Example 5: Recorded matter obtained using the color ink 4 by the above printing method.
Comparative Example 6: Recorded matter obtained by using the reaction solution 1 and the color ink 5 by the above printing method.
Printing is performed by first printing the reaction solution at 100% duty, and then printing 24 alphabetic characters with each color ink. The discharge amount of both the reaction liquid and ink is 0.07 μg / dot, and the density is 360 dpi.
The recording paper used for evaluation is as follows.
(1) Xerox P paper (Xerox Co., Ltd.)
(2) Rcopy 6200 paper (Ricoh Co., Ltd.)
(3) Xerox 4024 paper (manufactured by Xerox Corporation)
(4) Neenah Bond paper (made by Kimberly Clark)
(5) Xerox R paper (Xerox Co., Ltd., recycled paper)
(6) Yamayuri paper (Honshu Paper Co., Ltd., recycled paper)
The resulting recorded material is visually observed for the occurrence of bleeding and evaluated as follows.
(Double-circle): The clear character is obtained with no blurring on all the papers.
○: Some paper has whisker-like blurring.
Δ: All papers have whiskers.
X: The blur has occurred so that the outline of the character is not clear.
The evaluation results are as shown in the following table.
[Table 3]

[0153]
Evaluation 3: Abrasion resistance test (line marker resistance)
After the recorded matter printed in Evaluation 2 was dried at room temperature for 24 hours, the printed characters of the recorded matter were written at a writing pressure of 4.9 × 10 using a zebra aqueous fluorescent pen ZEBRA PEN2 (trademark).^FiveN / m²And visually observe the presence or absence of dirt and evaluate as follows.
○: No smearing occurs even after rubbing twice.
X: Dirt is generated by rubbing once.
The evaluation results were as shown in the following table.
[Table 4]

[0154]
Evaluation 4: Color bleed
Using the inkjet recording apparatus of FIG. 5, printing is performed on each of the following papers using the reaction liquid 1 and the yellow, magenta, and cyan inks of the color inks 1 to 5, respectively. The combinations are as follows.
Example 11: Recorded matter obtained by using the reaction liquid 1 and the color ink 1 by the above printing method.
Example 12: Recorded matter obtained by using the reaction liquid 1 and the color ink 2 by the above printing method.
Example 13: Recorded matter obtained by using the reaction liquid 2 and the color ink 1 by the above printing method.
Comparative Example 7: Recorded matter obtained using only the color ink 4 without using the reaction liquid in the above printing method.
Comparative Example 8: Recorded matter obtained by using the reaction liquid 1 and the color ink 5 by the above printing method.
The recording paper used for evaluation is shown below.
(1) Xerox P paper (Xerox Co., Ltd.)
(2) Rcopy 6200 paper (Ricoh Co., Ltd.)
(3) Xerox 4024 paper (manufactured by Xerox Corporation)
(4) Neenah Bond paper (made by Kimberly Clark)
(5) Xerox R paper (Xerox Co., Ltd., recycled paper)
(6) Yamayuri paper (Honshu Paper Co., Ltd., recycled paper)
In printing, first, the reaction liquid is printed at 100% duty, and then each color of the color ink (cyan, magenta, yellow) is printed. The presence or absence of non-uniform color mixing at the boundary of each color is visually observed and evaluated according to the following criteria. The discharge amount of both the reaction liquid and ink is 0.07 μg / dot, and the density is 360 dpi.
○: When there is no color mixing and the boundary is clear
△: When a whisker-like color mixture occurs
×: When the color is mixed so that the boundary is not clear
The evaluation results are as shown in the following table.
[Table 5]

[0155]
Evaluation 5: Storage stability
In a glass sample bottle, 50 cc of the following ink composition is placed and allowed to stand at 60 ° C. for 2 weeks to check for the presence of viscosity, sediment and foreign matter.
Example 15: Color ink 1 was subjected to this test.
Example 16: Color ink 2 was subjected to this test.
Example 17: Color ink 3 was subjected to this test.
Comparative Example 9: Color ink 4 was subjected to this test.
Comparative Example 10: Color ink 5 was subjected to this test.
Evaluation is performed as follows.
○: No sediment and foreign matter are generated, and there is no change in viscosity.
Δ: No sediment or foreign matter is generated, but there is a change in viscosity.
X: Sediment or foreign matter is generated.
The evaluation results were as shown in Table 7.
[0156]
Evaluation 6: Clogging reliability
1 is filled with yellow, magenta, and cyan inks of color inks 1 to 5, respectively, and alphanumeric characters are printed continuously for 10 minutes. Thereafter, the printer is stopped and left for one week in an environment of a temperature of 40 ° C. and a humidity of 25% without capping. Alphanumeric characters are printed again after being left, and the number of return operations required until a print quality equivalent to that before being left is obtained is checked.
The ink composition used for the test is as follows.
Example 15: Color ink 1 was subjected to this test.
Example 16: Color ink 2 was subjected to this test.
Example 17: Color ink 3 was subjected to this test.
Comparative Example 9: Color ink 4 was subjected to this test.
Comparative Example 10: Color ink 5 was subjected to this test.
Evaluation is judged according to the following criteria.
Print quality equivalent to the initial value is obtained with 0 to 2 return operations.
It was. : ○
Print quality equivalent to the initial one is obtained after 3 to 5 return operations
It was. : △
A print quality equivalent to the initial value can be obtained after 6 or more resetting operations.
It wasn't. : ×
The evaluation results are as shown in Table 7.
[0157]
Evaluation 7: Discharge stability
An ink jet printer MJ-700V2C (manufactured by Seiko Epson Corporation) is filled with the ink composition, the ejection amount is 0.7 μg / dot, the density is 360 dpi, and alphabet characters are continuously printed at room temperature. Observe for missing dots and ink splatter, and examine the time until it occurs 10 times or more.
The ink composition used for the test is as follows.
Example 15: Color ink 1 was subjected to this test.
Example 16: Color ink 2 was subjected to this test.
Example 17: Color ink 3 was subjected to this test.
Comparative Example 9: Color ink 4 was subjected to this test.
Comparative Example 10: Color ink 5 was subjected to this test.
Evaluation is performed as follows.
Missing dots or ink splatter for over 48 hours
Does not occur 10 times. : ◎
Missing dots or flying ink within 24-48 hours
Scattering occurs 10 times. : ○
Dot missing or ink jump within 1-24 hours
Scattering occurs 10 times. : △
Dot missing or ink splatter within 1 hour
Occurs 10 times or more. : ×
The evaluation results are as shown in the following table.
[Table 6]

[Brief description of the drawings]
FIG. 1 is a diagram showing an ink jet recording apparatus for carrying out a method according to the present invention. In this embodiment, a recording head and an ink tank are independent from each other, and an ink composition is supplied to the recording head by an ink tube. .
FIG. 2 is an enlarged view of a nozzle surface of a recording head, and reference numeral 1c denotes a nozzle surface in which a plurality of nozzles from which an ink composition is ejected are arranged in the vertical direction.
FIG. 3 is a diagram illustrating ink jet recording using the recording head of FIG. 2; In the figure, reference numeral 31 denotes a printed ink composition.
FIG. 4 is a view showing an ink jet recording apparatus for performing the method according to the present invention, and in this embodiment, a recording head and an ink tank are integrated.
FIG. 5 is a diagram showing an ink jet recording apparatus for carrying out the method according to the present invention. In this embodiment, the recording head and the ink tank are independent from each other, and the ink composition and the reaction liquid are transferred to the recording head by an ink tube. Supplied.
FIG. 6 is an enlarged view of a nozzle surface of a recording head, in which 51b is a nozzle surface of a reaction liquid, and 51c is a nozzle surface of an ink composition.
7 is a diagram illustrating ink jet recording using the recording head of FIG. 2; FIG. In the figure, 61 is a reaction liquid adhesion area, and 62 is a printing area where an ink composition is printed with the reaction liquid adhered.
FIG. 8 is a diagram illustrating another aspect of the recording head, in which all the discharge nozzles are arranged in the horizontal direction.
FIG. 9 is a view showing an ink jet recording apparatus for carrying out the method according to the present invention. In this embodiment, the recording head and the ink tank are integrated.
[Explanation of symbols]
1,51 Recording head
2,52 ink tank
3 Ink tube
22, 23, 24, 25 Ink discharge nozzle
31 Print area
21 Reaction liquid discharge nozzle
61 Reaction solution adhesion area
62 Print area

Claims (19)

On the recording medium,
An ink composition comprising a coloring material, water, a water-soluble organic solvent, and polymer fine particles, wherein the polymer fine particles have a film-forming ability and have an ultraviolet absorbing ability and a light stabilizing ability. An ink composition comprising a polymer;
A recording method comprising a step of forming an image by adhering a reaction liquid containing a reactive agent that forms an aggregate upon contact with the ink composition,
A recording method, wherein the ink composition and / or the reaction liquid is attached to a recording medium by an inkjet recording method.   The recording method according to claim 1, wherein the polymer fine particles are made of a polymer containing an ultraviolet absorber and a light stabilizer.   The ultraviolet absorber or light stabilizer is a benzophenone ultraviolet absorber, a benzotriazole ultraviolet absorber, a hindered phenol ultraviolet absorber, a salicylate ultraviolet absorber, a cyanoacrylate ultraviolet absorber, or a nickel complex ultraviolet ray. The recording method according to claim 2, wherein the recording method is selected from the group consisting of an absorber and a hindered amine light stabilizer.   The recording method according to claim 1, wherein the polymer fine particles are made of a polymer having a site having an ultraviolet absorbing ability and a light stabilizing ability in the structure.   5. The site having the ultraviolet absorbing ability or light stabilizing ability is selected from the group consisting of a benzophenone skeleton, a benzotriazole skeleton, a hindered phenol skeleton, a salicylate skeleton, a cyanoacrylate skeleton, and a hindered amine skeleton. Recording method described in 1.   The recording method according to claim 1, wherein the polymer fine particles have a glass transition point of 30 ° C. or lower.   The recording method according to claim 1, wherein the water-soluble organic solvent has a boiling point of 180 ° C. or higher.   The recording method according to claim 1, wherein the fine polymer particles are made of a polymer mainly composed of a thermoplastic polymer.   The thermoplastic polymer is an ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, polyethylene, polypropylene, polystyrene, poly (meth) acrylate ester, (meth) acrylic acid-styrene copolymer, (meta ) Acrylic acid ester- (meth) acrylic acid copolymer, styrene-maleic acid copolymer, styrene-itaconic acid ester copolymer, polyvinyl acetate, polyester, polyurethane, and polyamide. The recording method according to claim 8.   The recording method according to claim 1, wherein the polymer fine particles have a single particle structure.   The recording method according to claim 10, wherein the polymer fine particles have a functional group of either a carboxyl group or a sulfonic acid group.   The recording method according to claim 1, wherein the fine polymer particles have a core-shell structure including a core portion and a shell layer surrounding the core portion.   The recording method according to claim 12, wherein the shell layer has a functional group of either a carboxyl group or a sulfonic acid group.   The recording method according to claim 1, wherein a particle diameter of the polymer fine particles is 5 nm to 200 nm.   The recording method according to any one of claims 1 to 14, wherein the polymer fine particles are dispersed in an ink composition as dispersed particles of a polymer emulsion.   The recording method according to claim 15, wherein the polymer emulsion has a minimum film formation temperature of 30 ° C. or less.   The recording method according to claim 1, wherein the color material is a dye or a pigment.   The recording method according to claim 1, wherein the reaction solution comprises at least a reactant, a water-soluble organic solvent, and water.   The recording method according to claim 18, wherein the reactant is a polyvalent metal salt, polyallylamine or a derivative thereof.

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