JP2004107571A - Oil-base ink composition for inkjet printer, and electrophotographic liquid developer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide oil-base ink for inkjet printers in which a colorant is homogeneously dispersed in a fine particle state and which is excellent in dispersion stability of a colorant dispersion, has high ejecting stability, causing no clogging at a nozzle section, and is excellent in dryability on recording paper, water resistance and light fastness of a recorded image, and scratch resistance. <P>SOLUTION: Colored resin particles are produced by dispersion polymerization, in the presence of a polymerization initiator, of a dispersion comprising at least one monofunctional monomer (M), at least one dispersion stabilizer (P) mainly comprising a polymer which is soluble in a non-aqueous solvent and has a polymerizable double bond at the end of a substituent of a repeating unit component of the polymer, and seed particles comprising fine coloring component particles obtained by finely dispersing, in the non-aqueous solvent, a coloring component obtained by the surface treatment of a colorant. The colored resin particles thus produced are incorporated into the oil-base ink for inkjet printers and into the electrophotographic liquid developer. <P>COPYRIGHT: (C)2004,JPO

Description

【００１７】
一般式（Ｉ）中、Ｘ^０は−ＣＯＯ−、−ＯＣＯ−、−（ＣＨ_２）_ｋ−ＯＣＯ−、−（ＣＨ_２）_ｋ−ＣＯＯ−及び−Ｏ−から選ばれた１種或いはそれらの組み合わされた連結基を表わす。ｋは１〜３の整数を表す。
ａ^１とａ^２は、互いに同じでも異なってもよく、それぞれ水素原子、ハロゲン原子、シアノ基、炭化水素基、−ＣＯＯ−Ｚ^１又は炭化水素を介した−ＣＯＯ−Ｚ^１　（Ｚ^１は水素原子又は置換されてもよい炭化水素基を示す）を表す。
Ｑ^０は炭素数４〜２２の脂肪族基を表す。
【００１８】
【化４】

【００１９】
一般式（ＩＩ）中、Ｘ^１とＸ^３は、互いに同じでも異なってもよく、それぞれ−ＣＯＯ−、−ＯＣＯ−、−（ＣＨ_２）_ｋ　ＣＯＯ−、−（ＣＨ_２）_ｋＯＣＯ−、−Ｏ−、−ＳＯ_２−、−ＣＯＮＨＣＯＯ−、−ＣＯＮＨＣＯＮＨ−、−ＣＯＮ（Ｚ^２）−、又は−ＳＯ_２Ｎ（Ｚ^２）−を表す。ここでＺ^２は水素原子または炭素数１〜２２の炭化水素基を示し、ｋは１〜４の整数を示す。
Ｗは結合基Ｘ^１と結合基Ｘ^２とを連結する基で、少なくとも１つの炭素原子、酸素原子、イオウ原子、ケイ素原子又は窒素原子からなるものを表す。
ｂ^１とｂ^２、ｃ^１とｃ^２は、一般式（Ｉ）におけるａ^１とａ^２と同義である。
【００２０】
（３）着色剤が有機顔料及び無機顔料から選択される少なくとも一種の顔料であり、着色成分が、該着色剤をポリマー被覆することにより表面処理されたものである上記（１）記載のインクジェットプリンタ用油性インク組成物。
（４）シード粒子が、表面処理された着色成分を顔料分散剤により非水溶媒中に微粒子状に分散安定化して得た着色成分微粒子である上記（１）記載のインクジェットプリンタ用油性インク組成物。
【００２１】
（５）体積比抵抗１０^９Ωｃｍ以上の非水溶媒中に、着色剤を表面処理した着色成分を該非水溶媒中に微粒子状に分散して得た着色成分微粒子をシード粒子として、一官能性単量体（Ｍ）の少なくとも一種と、該非水溶媒に可溶であって重合体繰り返し成分の置換基の末端に、重合性二重結合基を有する重合体を主成分とする分散安定化剤（Ｐ）の少なくとも一種とを加え、重合開始剤の存在下に分散重合させることにより得られる着色樹脂粒子を含有することを特徴とする電子写真用液体現像剤。
（６）分散安定化剤（Ｐ）が、上記一般式（Ｉ）で示される該非水溶媒に可溶である重合体成分Ａと、上記一般式（ＩＩ）で示される重合体繰り返し成分の置換基の末端に、重合性二重結合基を有する重合体成分Ｂとを主成分とする分散安定化剤であることを特徴とする上記（５）記載の電子写真用液体現像剤。
【００２２】
（７）着色剤が有機顔料及び無機顔料から選択される少なくとも一種の顔料であり、着色成分が、該着色剤をポリマー被覆することにより表面処理されたものである上記（５）記載の電子写真用液体現像剤。
（８）シード粒子が、表面処理された着色成分を顔料分散剤により非水溶媒中に微粒子状に分散安定化して得た着色成分微粒子である上記（５）記載の電子写真用液体現像剤。
【００２３】
（９）誘電率１．５〜２０及び表面張力１５〜６０ｍＮ／ｍ（２５℃において）を有する非水溶媒中に、着色剤を表面処理した着色成分を該非水溶媒中に微粒子状に分散して得た着色成分微粒子をシード粒子として、一官能性単量体（Ｍ）の少なくとも一種と、該非水溶媒に可溶であって重合体繰り返し成分の置換基の末端に、重合性二重結合基を有する重合体を主成分とする分散安定化剤（Ｐ）の少なくとも一種とを加えた分散液を、重合開始剤の存在下に分散重合させることを特徴とする着色樹脂粒子の製造方法。
（１０）分散安定化剤（Ｐ）が、上記一般式（Ｉ）で示される該非水溶媒に可溶である重合体成分Ａと、上記一般式（ＩＩ）で示される重合体繰り返し成分の置換基の末端に、重合性二重結合基を有する重合体成分Ｂとを主成分とする分散安定化剤であることを特徴とする上記（９）記載の着色樹脂粒子の製造方法。
【００２４】
（１１）着色剤が有機顔料及び無機顔料から選択される少なくとも一種の顔料であり、該着色剤をポリマー被覆して表面処理することを特徴とする上記（９）記載の着色樹脂粒子の製造方法。
（１２）着色成分微粒子を、表面処理された着色成分を顔料分散剤により該非水溶媒中に微粒子状に分散安定化することにより得ることを特徴とする上記（９）記載の着色樹脂粒子の製造方法。
【００２５】
【発明の実施の形態】
以下に本発明について詳細に述べる。
本発明のインクジェットプリンタ用油性インク組成物に使用される非水溶媒は、非極性の絶縁性溶剤であり、誘電率１．５〜２０及び表面張力１５〜６０ｍＮ／ｍ（２５℃にて）であることが好ましい。また、電子写真用液体現像剤に使用される非水溶媒は、体積比抵抗１０^９Ωｃｍ以上であることが好ましい。更に望まれる特性としては、毒性の少ないこと、引火性が少ないこと、臭気が少ないことである。
【００２６】
かかる非水溶媒としては、直鎖状もしくは分岐状の脂肪族炭化水素、脂環式炭化水素、芳香族炭化水素、石油ナフサ及びこれらのハロゲン置換体等から選ばれた溶媒が挙げられる。例えばヘキサン、オクタン、イソオクタン、デカン、イソデカン、デカリン、ノナン、ドデカン、イソドデカン、エクソン社のアイソパーＥ、アイソパーＧ、アイソパーＨ、アイソパーＬ、フィリップ石油社のソルトール、出光石油化学社のＩＰソルベント、石油ナフサではシェル石油化学社のＳ．Ｂ．Ｒ．、シェルゾール７０、シエルゾール７１、モービル石油社のベガゾール等から選ばれた溶媒を単独又は混合して用いることができる。
【００２７】
好ましい炭化水素溶剤としては、沸点が１５０〜３５０℃の範囲にある高純度のイソパラフィン系炭化水素が挙げられ、市販品としては前述のエクソン化学製のアイソパーＧ，Ｈ，Ｌ，Ｍ，Ｖ（商品名）、ノーパー１２，１３，１５（商品名）、出光石油化学製のＩＰソルベント１６２０，２０２８（商品名）、日本石油化学製のアイソゾール３００，４００（商品名）、アムスコＯＭＳ、アムスコ４６０溶剤（アムスコ；スピリッツ社の商品名）等が挙げられる。これらの製品は、極めて純度の高い脂肪族飽和炭化水素であり、２５℃における粘度は３ｃＳｔ以下、２５℃における表面張力は２２．５〜２８．０ｍＮ／ｍ、２５℃における比抵抗は１０^１０Ω・ｃｍ以上である。また、反応性が低く安定であり、低毒性で安全性が高く、臭気も少ないという特徴がある。
【００２８】
ハロゲン置換の炭化水素系溶媒としてフルオロカーボン系溶媒があり、例えばＣ_７Ｆ_１６、Ｃ_８Ｆ_１８などのＣ_ｎＦ_２ｎ＋２で表されるパーフルオロアルカン類（住友３Ｍ社製「フロリナートＰＦ５０８０」、「フローリナートＰＦ５０７０」（商品名）等）、フッ素系不活性液体（住友３Ｍ社製「フロリナートＦＣシリーズ」（商品名）等）、フルオロカーボン類（デュポンジャパンリミテッド社製「クライトックスＧＰＬシリーズ」（商品名）等）、フロン類（ダイキン工業株式会社製「ＨＣＦＣ−１４１ｂ　」（商品名）等）、［Ｆ（ＣＦ_２）_４ＣＨ_２ＣＨ_２Ｉ］、［Ｆ（ＣＦ_２）_６Ｉ］等のヨウ素化フルオロカーボン類（ダイキンファインケミカル研究所製「Ｉ−１４２０」、「Ｉ−１６００」（商品名）等）等が挙げられる。
【００２９】
本発明で使用される非水系の溶媒として、更に高級脂肪酸エステルや、シリコーンオイルも使用できる。シリコーンオイルの具体例としては、低粘度の合成ジメチルポリシロキサンが挙げられ、市販品としては、信越シリコーン製のＫＦ９６Ｌ（商品名）、東レ・ダウコーニング・シリコーン製のＳＨ２００（商品名）等が挙げられる。
シリコーンオイルとしてはこれらの具体例に限定されるものではない。これらのジメチルポリシロキサンは、その分子量により非常に広い粘度範囲のものが入手可能であるが、１〜２０ｃＳｔの範囲のものを用いるのが好ましい。これらのジメチルポリシロキサンは、イソパラフィン系炭化水素同様、１０^１０Ω・ｃｍ以上の体積抵抗率を有し、高安定性、高安全性、無臭性といった特徴を有している。またこれらのジメチルポリシロキサンは、表面張力が低いことに特徴があり、１８〜２１ｍＮ／ｍの表面張力を有している。
【００３０】
これらの有機溶媒とともに、混合して使用できる溶媒としては、アルコール類（例えばメチルアルコール、エチルアルコール、プロピルアルコール、ブチルアルコール、フッ化アルコール等）、ケトン類（例えばアセトン、メチルエチルケトン、シクロヘキサノン等）、カルボン酸エステル類（例えば酢酸メチル、酢酸エチル、酢酸プロピル、酢酸ブチル、プロピオン酸メチル、プロピオン酸エチル等）、エーテル類（例えばジエチルエーテル、ジプロピルエーテル、テトラヒドロフラン、ジオキサン等）及びハロゲン化炭化水素類（例えばメチレンジクロリド、クロロホルム、四塩化炭素、ジクロロエタン、メチルクロロホルム等）等の溶媒が挙げられる。
【００３１】
次に本発明の表面処理された着色成分について詳細に述べる。
本発明の表面処理された着色成分（以下単に「着色成分」と称することもある）は、着色剤を表面処理したものであり、該着色剤としては、特に限定されるものではなく、一般に市販されているすべての有機顔料及び無機顔料が挙げられる。
【００３２】
例えば、イエロー色を呈するものとして、Ｃ．Ｉ．ピグメントイエロー１（ファストイエローＧ等），　Ｃ．Ｉ．ピグメントイエロー７４の如きモノアゾ顔料、Ｃ．Ｉ．ピグメントイエロー１２（ジスアジイエローＡＡＡ等），　Ｃ．Ｉ．ピグメントイエロー１７の如きジスアゾ顔料、　Ｃ．Ｉ．ピグメントイエロー１８０の如き非ベンジジン系のアゾ顔料、　Ｃ．Ｉ．ピグメントイエロー１００（タートラジンイエローレーキ等）の如きアゾレーキ顔料、　Ｃ．Ｉ．ピグメントイエロー９５（縮合アゾイエローＧＲ等）の如き縮合アゾ顔料、　Ｃ．Ｉ．ピグメントイエロー１１５（キノリンイエローレーキ等）の如き酸性染料レーキ顔料、Ｃ．Ｉ．ピグメントイエロー１８（チオフラビンレーキ等）の如き塩基性染料レーキ顔料、フラバントロンイエロー（Ｙ−２４）の如きアントラキノン系顔料、イソインドリノンイエロー３ＲＬＴ（Ｙ−１１０）の如きイソインドリノン顔料、キノフタロンイエロー（Ｙ−１３８）の如きキノフタロン顔料、イソインドリンイエロー（Ｙ−１３９）の如きイソインドリン顔料、　Ｃ．Ｉ．ピグメントイエロー１５３（ニッケルニトロソイエロー等）の如きニトロソ顔料、　Ｃ．Ｉ．ピグメントイエロー１１７（銅アゾメチンイエロー等）の如き金属錯塩アゾメチン顔料等が挙げられる。
【００３３】
マゼンタ色を呈するものとして、Ｃ．Ｉ．ピグメントレッド３（トルイジンレッド等）の如きモノアゾ系顔料、　Ｃ．Ｉ．ピグメントレッド３８（ピラゾロンレッドＢ等）の如きジスアゾ顔料、　Ｃ．Ｉ．ピグメントレッド５３：１（レーキレッドＣ等）やＣ．Ｉ．ピグメントレッド５７：１（ブリリアントカーミン６Ｂ）の如きアゾレーキ顔料、　Ｃ．Ｉ．ピグメントレッド１４４（縮合アゾレッドＢＲ等）の如き縮合アゾ顔料、　Ｃ．Ｉ．ピグメントレッド１７４（フロキシンＢレーキ等）の如き酸性染料レーキ顔料、　Ｃ．Ｉ．ピグメントレッド８１（ローダミン６Ｇ’レーキ等）の如き塩基性染料レーキ顔料、　Ｃ．Ｉ．ピグメントレッド１７７（ジアントラキノニルレッド等）り如きアントラキノン系顔料、Ｃ．Ｉ．ピグメントレッド８８（チオインジゴボルドー等）の如きチオインジゴ顔料、　Ｃ．Ｉ．ピグメントレッド１９４（ペリノンレッド等）の如きペリノン顔料、　Ｃ．Ｉ．ピグメントレッド１４９（ペリレンスカーレット等）の如きペリレン顔料、　Ｃ．Ｉ．ピグメントレッド１２２（キナクリドンマゼンタ等）の如きキナクリドン顔料、　Ｃ．Ｉ．ピグメントレッド１８０（イソインドリノンレッド２ＢＬＴ等）の如きイソインドリノン顔料、　Ｃ．Ｉ．ピグメントレッド８３（マダーレーキ等）の如きアリザリンレーキ顔料等が挙げられる。
【００３４】
シアン色を呈する顔料として、Ｃ．Ｉピグメントブルー２５（ジアニシジンブルー等）の如きジスアゾ系顔料、　Ｃ．Ｉ．ピグメントブルー１５（フタロシアニンブルー等）の如きフタロシアニン顔料、　Ｃ．Ｉ．ピグメントブルー２４（ピーコックブルーレーキ等）の如き酸性染料レーキ顔料、　Ｃ．Ｉ．ピグメントブルー１（ビクロチアピュアブルーＢＯレーキ等）の如き塩基性染料レーキ顔料、　Ｃ．Ｉ．ピグメントブルー６０（インダントロンブルー等）の如きアントラキノン系顔料、　Ｃ．Ｉ．ピグメントブルー１８（アルカリブルーＶ−５：１）の如きアルカリブルー顔料等が挙げられる。
【００３５】
ブラック色を呈する顔料として、ＢＫ−１（アニリンブラック）の如きアニリンブラック系顔料等の有機顔料や酸化鉄顔料、及びファーネスブラック、ランプブラック、アセチレンブラック、チャンネルブラック等のカーボンブラック顔料類が挙げられる。
また、金、銀、銅などの色再現のために金属粉の応用も挙げられる。
【００３６】
着色剤の表面処理方法としては、技術情報協会発行の「顔料分散技術」第５章に記載されている、ロジン処理、ポリマー処理、グラフト化処理、プラズマ処理等の方法が適用できる。
【００３７】
「ロジン処理」とは、顔料とロジンを機械的に混練し顔料表面にロジンを処理する方法や，顔料の水性スラリーにロジンのアルカリ水溶液を加えた後にアルカリ土類塩や酸などを加えてロジンの難溶性塩または遊離酸を顔料粒子表面に析出させる方法などである。ロジン処理では通常、顔料の数％から２０％程度のロジンが用いられ、▲１▼顔料の結晶成長防止効果により微細で透明性の大きな顔料が得られること、▲２▼粒子の乾燥凝集が弱くなるために機械的分散が容易になること、▲３▼顔料表面の親油性を増大させることにより油性ビヒクルに対するぬれを改善するなどに大きな効果があり、特に印刷インキの分野で多く使用されている。
【００３８】
「グラフト化処理」とは、カーボンブラック、およびシリカや酸化チタンなどの無機微粒子、さらには有機顔料などの表面に存在する水酸基やカルボキシル基やアミノ基などの官能基とポリマーとのグラフト化反応を行うものである。顔料表面へのポリマーのグラフト化反応には、（１）顔料微粒子の存在下で、重合開始剤を用いてビニルモノマーの重合を行い、系内で生成する生長ポリマーを顔料粒子表面の官能基で停止することによる方法、（２）顔料微粒子表面へ導入した重合開始基からグラフト鎖を生長させる方法、および（３）顔料微粒子表面の官能基とポリマー末端の官能基との高分子反応による方法等がある。
【００３９】
「プラズマ処理」とは、低温プラズマや熱プラズマにより顔料粉体表面の改質を行うものである。低温プラズマによる顔料表面の処理の具体例としては、（１）酸素や窒素などの非重合性気体のプラズマ照射による改質、（２）重合性気体を用いたプラズマ重合膜形成による改質、（３）プラズマ照射によって基材表面に活性種を形成させる第１段階と、照射後モノマーと接触させ、あと反応でグラフト重合を進行させる第２段階の二段階プロセスよりなるプラズマ開始グラフト重合反応による改質などが挙げられる。
【００４０】
着色剤の表面処理方法としては、着色剤の分散性を向上させると共に、分散された着色成分をシード粒子として非水溶媒中で分散重合させる観点から、以下に述べるポリマー処理が特に好ましい。
【００４１】
ポリマー処理の代表的方法としては、技術情報協会発行の「顔料分散技術」９９頁以降に記載のｉｎ−ｓｉｔｕ重合法を利用した化学的方法、相分離法（コアセルベーション）を利用した方法、顔料分散時に機械的な力で処理する方法などが挙げられる。
【００４２】
ｉｎ−ｓｉｔｕ重合法としては、顔料およびポリマーの系を分散した後懸濁重合する方法、分散剤の存在下顔料を水系に分散し極性ポリマー、ビニル系ポリマー、多官能橋かけポリマーを加えて重合する方法、顔料を分散したモノマーを塊状重合した後懸濁重合または乳化重合することにより顔料への吸着が十分行えるようにする方法などがある。相分離法（コアセルベーション）としては、ポリマー溶液中に顔料を分散させた後、何らかの方法でポリマーの溶解度を下げ溶液系からポリマーを顔料粒子上へ析出させる方法が挙げられ、化学的方法（ｉｎ−ｓｉｔｕ重合法）に比べ広い範囲のポリマーを選べる特徴がある。顔料を分散した樹脂溶液に非溶媒を加えて顔料表面に樹脂を析出させる方法や、水溶性ポリマーや水溶性樹脂溶液に顔料を微細に分散した後、ｐＨを調整してこれらを顔料表面に析出させる方法はロジン処理を含めて広く用いられている。酸可溶性の含窒素アクリル樹脂の酸溶液中で顔料を分散させた後、ｐＨを上げてポリマーを顔料表面で不溶化したものは塗料、印刷インキでの凝集防止、流動性、光沢、着色力向上に効果がみられている。機械的な力でポリマー処理する方法を例示すると、ポリマーと顔料を予め顔料分が５〜９５％になる様に混合した後に、加熱しながらニーダー、三本ロールなどで混練し、ピンミル等で粉砕するものである。フラッシング樹脂処理という方法も機械的なポリマー処理方法に含まれる。
【００４３】
ポリマー処理に用いる樹脂としては、非水溶媒中で顔料の分散性を向上させると共に、この分散された着色成分微粒子をシード粒子として非水溶媒中で分散重合させる際の加熱分散安定性を付与するものであることが好ましく、液体現像剤で従来使用されている樹脂も使用することができる。
【００４４】
好ましい樹脂としては、着色剤に吸着し、且つ非水系溶媒中に良く分散する機能を有するために、溶媒に溶媒和する部分と溶媒に溶媒和しにくい部分及び極性基を有する部分を持っている樹脂が好ましい。例えば、重合後に溶媒に溶媒和するモノマーとしては、ラウリルメタクリレート、ステアリルメタクリレート、２−エチルヘキシルメタクリレート、セチルメタクリレート等が挙げられる。重合後に溶媒に溶媒和しにくいモノマーとしては、メチルメタクリレート、エチルメタクリレート、イソプロピルメタクリレート、スチレン、ビニルトルエン等が挙げられる。極性基を含むモノマーとしては、アクリル酸、メタクリル酸、イタコン酸、フマル酸、マレイン酸、スチレンスルホン酸またはそのアルカリ塩などの酸性基モノマーと、ジメチルアミノエチルメタクリレート、ジエチルアミノエチルメタクリレート、ビニルピリジン、ビニルピロリジン、ビニルピペリジン、ビニルラクタムなどの塩基性基モノマーが挙げられる。
【００４５】
ポリマー処理に用いる樹脂の具体例としては、オレフィン重合体および共重合体（例えばポリエチレン、ポリプロピレン、ポリイソブチレン、エチレン−酢酸ビニル共重合体、エチレン−アクリレート共重合体、エチレン−メタクリレート共重合体、エチレン−メタクリル酸共重合体等）、スチレンおよびその誘導体の重合体ならびに共重合体（例えばブタジエン−スチレン共重合体、イソプレン−スチレン共重合体、スチレン−メタクリレート共重合体、スチレン−アクリレート共重合体等）、アクリル酸エステル重合体および共重合体、メタクリル酸エステル重合体および共重合体、イタコン酸ジエステル重合体および共重合体、無水マレイン酸共重合体、ロジン樹脂、水素添加ロジン樹脂、石油樹脂、水素添加石油樹脂、マレイン酸樹脂、テルペン樹脂、水素添加テルペン樹脂、クロマン−インデン樹脂、環化ゴム−メタクリル酸エステル共重合体、環化ゴム−アクリル酸エステル共重合体などが挙げられる。
【００４６】
本発明の着色剤とポリマー処理に用いられる樹脂の割合は、着色剤／樹脂の重量比で好ましくは９５／５〜５／９５の範囲、より好ましくは８０／２０〜１０／９０の範囲である。
【００４７】
更に表面処理された着色成分として、一般に市販されている加工顔料も用いることができる。市販加工顔料の具体例としては、チバスペシャリティケミカルズ社のマイクロリス顔料等が挙げられ、好ましい加工顔料の例としては、ロジンエステル樹脂で顔料を被覆したマイクロリス−Ｔ顔料が挙げられる。
【００４８】
本発明においては、上記表面処理された着色成分は、非水溶媒中に微粒子状に分散されて着色成分微粒子を得、これをシード粒子として更に分散重合させるものである。まず、着色成分の分散工程について述べる。
該分散工程では、着色成分を微粒子状に分散し且つ非水溶媒中で分散安定化させるために顔料分散剤を使用することが好ましい。
【００４９】
本発明に使用することができる、表面処理された着色成分を非水溶媒中で微粒子状に分散するための顔料分散剤としては、該非水溶媒中で適用される一般の顔料分散剤が使用できる。顔料分散剤としては前記非極性の絶縁性溶媒に相溶し、安定的に着色成分を微粒子分散できるものであれば良い。
【００５０】
顔料分散剤の具体例としては、ソルビタン脂肪酸エステル（ソルビタンモノオレエート、ソルビタンモノラウレート、ソルビタンセスキオレエート、ソルビタントリオレエート等）、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ソルビタンモノステアレート、ポリオキシエチレンソルビタンモノオレエート等）、ポリエチレングリコール脂肪酸エステル（ポリオキシエチレンモノステアレート、ポリエチレングリコールジイソステアレート等）、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ノニルフェニルエーテル、ポリオキシエチレンオクチルフェニルエーテル等）、脂肪族ジエタノールアミド系などのノニオン系界面活性剤、及び高分子系分散剤としては、分子量１０００以上の高分子化合物が良く、例えば、スチレン−マレイン酸樹脂、スチレン−アクリル樹脂、ロジン、ＢＹＫ−１６０、１６２、１６４、１８２（ビックケミー社製のウレタン系高分子化合物）、ＥＦＫＡ−４７、ＬＰ−４０５０（ＥＦＫＡ社製のウレタン系分散剤）、ソルスパーズ２４０００（ゼネカ社製のポリエステル系高分子化合物）、ソルスパース１７０００（ゼネカ社の脂肪族ジエタノールアミド系）等が挙げられる。
【００５１】
高分子系顔料分散剤としては上記の他に更に、溶媒に溶媒和するラウリルメタクリレート、ステアリルメタクリレート、２−エチルヘキシルメタクリレート、セチルメタクリレート等のモノマーと、溶媒に溶媒和しにくいメチルメタクリレート、エチルメタクリレート、イソプロピルメタクリレート、スチレン、ビニルトルエン等のモノマー及び極性基を有する部分からなるランダム共重合体、又は特開平３−１８８４６９号に開示されているグラフト共重合体が挙げられる。上述の極性基を含むモノマーとしては、アクリル酸、メタクリル酸、イタコン酸、フマル酸、マレイン酸、スチレンスルホン酸またはそのアルカリ塩などの酸性基モノマーと、ジメチルアミノエチルメタクリレート、ジエチルアミノエチルメタクリレート、ビニルピリジン、ビニルピロリジン、ビニルピペリジン、ビニルラクタムなどの塩基性基モノマーが挙げられる。また、この他にはスチレン―ブタジエン共重合体、特開昭６０−１０２６３号に開示されているスチレンと長鎖アルキルメタクリレートのブロック共重合体等が挙げられる。好ましい顔料分散剤としては、特開平３−１８８４６９号に開示されているグラフト共重合体等が挙げられる。
【００５２】
顔料分散剤の使用量は、着色剤１００重量部に対して、０．１〜３００重量部が好ましい。顔料分散剤の添加量が０．１重量部より少ないと着色成分の分散効果が小さく好ましくない。また、３００重量部より多く用いても用いた分の効果が得られない。
【００５３】
表面処理された着色剤を、非水溶媒中に分散させるにおいて、顔料分散剤を使用する方法としては、例えば次のような方法があり、これらのいずれによっても目的とする効果が得られる。
【００５４】
１．表面処理された着色剤と顔料分散剤を予め混合して得られる着色成分組成物を非水系溶媒中に添加して分散する。
２．非水系溶媒に表面処理された着色剤と顔料分散剤を別々に添加して分散する。
３．非水系溶媒に表面処理された着色剤と顔料分散剤を予め別々に分散し得られた分散体を混合する。この場合、顔料分散剤を溶剤のみで分散しても良い。
４．非水系溶媒に表面処理された着色剤を分散した後、得られた着色成分分散体に顔料分散剤を添加する。
【００５５】
上記の表面処理された着色剤（着色成分）は、非水系溶媒中で混合または分散させて、着色成分微粒子とすることができる。非水系溶媒中で混合又は分散する機械としては、ディゾルバー、ハイスピードミキサー、ホモミキサー、ニーダー、ボールミル、ロールミル、サンドミル、アトライター等が使用できる。この分散工程での着色成分（加工顔料等）の分散平均粒径の範囲は０．０１〜１０μｍである。インク中の着色成分の好ましい分散平均粒径範囲としては０．０１〜１．０μｍである。
【００５６】
次に上記分散された着色成分微粒子をシード粒子（シード）として、このシード粒子に一官能性単量体（Ｍ）を添加して分散重合させる工程について説明する。
非水溶媒中に着色成分を微粒子状に分散させシード粒子とした中で、一官能性単量体（Ｍ）と、重合体繰返し成分の置換基の末端に、重合性二重結合基を有する分散安定化剤（Ｐ）を加えた重合系を、重合開始剤の存在下に重合させることにより、本発明の着色剤を内包した着色樹脂粒子が得られる。単量体（Ｍ）は、該非水溶媒に可溶であるがその重合する事によって該非水溶媒に不溶性となる単量体であればいずれでもよい。
具体的には、例えば下記一般式（ＩＩＩ）で表される重合単量体が挙げられる。
【００５７】
【化５】

【００５８】
一般式（ＩＩＩ）中、Ｘ^２は−ＣＯＯ−、−ＯＣＯ−、−ＣＨ_２ＯＣＯ−、−ＣＨ_２ＣＯＯ−、−Ｏ−、−ＣＯＮＨＣＯＯ−、−ＣＯＮＨＯＣＯ−、−ＳＯ_２−、−ＣＯＮ（Ｚ^２）−、−ＳＯ_２Ｎ（Ｚ^２）−、またはフェニレン基（以下、フェニレン基を「−Ｐｈ−」と記載することもある。なお、フェニレン基は１，２−、１，３−および１，４−フエニレン基を包含する。）を表す。ここでＺ^２は、水素原子または炭素数１〜８の置換されていてもよい脂肪族基（たとえば、メチル基、エチル基、プロピル基、ブチル基、２−クロロエチル基、２−ブロモエチル基、２−シアノエチル基、２−ヒドロキシエチル基、ベンジル基、クロロベンジル基、メチルベンジル基、メトキシベンジル基、フェネチル基、３−フェニルプロピル基、ジメチルベンジル基、フロロベンジル基、２−メトキシエチル基、３−メトキシプロピル基等）を表す。
【００５９】
Ｑ^２は水素原子または炭素数１〜６の置換されてもよい脂肪族基（例えば、メチル基、エチル基、プロピル基、ブチル基、２−クロロエチル基、２，２−ジクロロエチル基、２，２，２−トリフロロエチル基、２−ブロモエチル基、２−ヒドロキシエチル基、２−ヒドロキシプロピル基、２，３−ジヒドロキシプロピル基、２−ヒドロキシ−３−クロロプロピル基、２−シアノエチル基、３−シアノプロピル基、２−ニトロエチル基、２−メトキシエチル基、２−メタンスルホニルエチル基、２−エトキシエチル基、３−ブロモプロピル基、４−ヒドロキシブチル基、２−フルフリルエチル基、２−チエニルエチル基、２−カルボキシエチル基、３−カルボキシプロピル基、４−カルボキシブチル基、２−カルボキシアミドエチル基、３−スルホアミドプロピル基、２−Ｎ−メチルカルボキシアミドエチル基、シクロペンチル基、クロロシクロヘキシル基、ジクロロヘキシル基等）を表す。
【００６０】
ｄ^１　およびｄ^２　は互いに同じでも異なっていてもよく、好ましくは水素原子、ハロゲン原子（例えば、塩素原子、臭素原子等）、シアノ基、炭素数１〜３のアルキル基（例えばメチル基、エチル基、プロピル基等）、−ＣＯＯ−Ｌ^１または−ＣＨ_２−ＣＯＯ−Ｌ^１〔ここでＬ^１は水素原子、または置換されてもよい炭素数１０以下の炭化水素基（例えば、アルキル基、アルケニル基、アラルキル基、アリール基等を表す）を表す。
【００６１】
具体的な単量体（Ｍ）としては、例えば炭素数１〜６の脂肪族カルボン酸（酢酸、プロピオン酸、酪酸、モノクロロ酢酸、トリフロロプロピオン酸等）のビニルエステル類あるいはアリルエステル類；アクリル酸、メタクリル酸、クロトン酸、イタコン酸、マレイン酸等の不飽和カルボン酸の炭素数１〜４の置換されてもよいアルキルエステル類またはアミド類（アルキル基として例えばメチル基、エチル基、プロピル基、ブチル基、２−クロロエチル基、２−ブロモエチル基、２−ヒドロキシエチル基、２−シアノエチル基、２−ニトロエチル基、２−メトキシエチル基、２−メタンスルホニルエチル基、２−ベンゼンスルホニルエチル基、２−カルボキシエチル基、４−カルボキシブチル基、３−クロロプロピル基、２−ヒドロキシ−３−クロロプロピル基、２−フルフリルエチル基、２−チエニルエチル基、２−カルボキシアミドエチル基等）；スチレン誘導体（例えば、スチレン、ビニルトルエン、α−メチルスチレン、ビニルナフタレン、クロロスチレン、ジクロロスチレン、ブロモスチレン、ビニルベンゼンカルボン酸、ビニルベンゼンスルホン酸、クロロメチルスチレン、ヒドロキシメチルスチレン、メトキシメチルスチレン、ビニルベンゼンカルボキシアミド、ビニルベンゼンスルホアミド等）；アクリル酸、メタクリル酸、クロトン酸、マレイン酸、イタコン酸等の不飽和カルボン酸；マレイン酸、イタコン酸の環状酸無水物；アクリロニトリル；メタクリロニトリル；重合性二重結合基含有のヘテロ環化合物（具体的には、例えば高分子学会編「高分子データハンドブック−基礎編−」、ｐ１７５〜１８４、培風舘（１９８６年刊）に記載の化合物、例えば、Ｎ−ビニルピリジン、Ｎ−ビニルイミダゾール、Ｎ−ビニルピロリドン、ビニルチオフェン、ビニルテトラヒドロフラン、ビニルオキサゾリン、ビニルチアゾール、Ｎ−ビニルモルホリン等）等が挙げられる。
単量体（Ｍ）は、上記の中から少なくとも一種以上選択されたモノマーを主成分とする。
【００６２】
本発明では、更に、単量体（Ｍ）と共重合可能な、一般式　−Ｎ（Ｒ^１）（Ｒ^２）で示されるアミノ基を含有する、塩基性の単量体（Ｂ）を含有しても良い。
Ｒ^１　、Ｒ^２　は、各々同じでも異なってもよく、好ましくは水素原子又は炭素数１〜２２の置換されてもよいアルキル基（例えば、メチル基、エチル基、プロピル基、ブチル基、ヘキシル基、ヘプチル基、オクチル基、ノニル基、デシル基、ドデシル基、トリデシル基、テトラデシル基、ヘキサデシル基、オクタデシル基、エイコシル基、ドコシル基、２−クロロエチル基、２−ブロモエチル基、２−シアノエチル基、２−メトキシカルボニルエチル基、２−メトキシエチル基、３−ブロモプロピル基等）、炭素数４〜１８の置換されてもよいアルケニル基（例えば、２−メチル−１−プロペニル基、２−ブテニル基、２−ペンテニル基、３−メチル−２−ペンテニル基、１−ペンテニル基、１−ヘキセニル基、２−ヘキセニル基、４−メチル−２−ヘキセニル基、デセニル基、ドデセニル基、トリデセニル基、ヘキサデセニル基、オクタデセニル基、リノレイル基等）、炭素数７〜１２の置換されてもよいアラルキル基（例えば、ベンジル基、フェネチル基、３−フェニルプロピル基、ナフチルメチル基、２−ナフチルエチル基、クロロベンジル基、ブロモベンジル基、メチルベンジル基、エチルベンジル基、メトキシベンジル基、ジメチルベンジル基、ジメトキシベンジル基等）、炭素数５〜８の置換されてもよい脂環式基（例えば、シクロヘキシル基、２−シクロヘキシルエチル基、２−シクロペンチルエチル基等）または炭素数６〜１２の置換されてもよい芳香族基（例えば、フェニル基、ナフチル基、トリル基、キシリル基、プロピルフェニル基、ブチルフェニル基、オクチルフェニル基、ドデシルフェニル基、メトキシフェニル基、エトキシフェニル基、ブトキシフェニル基、デシルオキシフェニル基、クロロフェニル基、ジクロロフェニル基、ブロモフェニル基、シアノフェニル基、アセチルフェニル基、メトキシカルボニルフェニル基、エトキシカルボニルフェニル基、ブトキシカルボニルフェニル基、アセトアミドフェニル基、プロピオアミドフェニル基、ドデシロイルアミドフェニル基等）が挙げられる。
【００６３】
また、Ｒ^１とＲ^２は環を形成しても良く、具体的には、ヘテロ原子（例えば酸素原子、窒素原子、イオウ原子等）を含有してもよい環形成の有機残基を表す。形成される環状アミノ基としては、例えばモルホリノ基、ピペリジノ基、ピリジニル基、イミダゾリル基、キノリル基、等が挙げられる。これらのアミノ基は、塩基性単量体の分子中に複数個含有されていてもよい。
本発明の着色樹脂粒子は、共重合成分としてアミノ基含有の塩基性単量体（Ｂ）を用いることで、粒子自身の表面が正荷電を発現し、非水系溶媒中に分散された粒子の分散安定性が向上する。これは粒子同志の近接時の荷電反発効果によるものと推測される。
塩基性単量体（Ｂ）は、単量体（Ｍ）の総量に対して、好ましくは１〜４５重量％、より好ましくは３〜３０重量％で用いる。
以下に、塩基性単量体（Ｂ）の具体例を示すが、本発明の範囲はこれに限定されるものではない。
【００６４】
【化６】

【００６５】
本発明では、単量体（Ｍ）と共重合可能な、−ＰＯ_３Ｈ_２基、−ＳＯ_３Ｈ基及び−ＳＯ_２Ｈ基から選ばれる少なくとも１つの酸性基を含有する酸性単量体（Ａ）を更に併用してもよい。酸性単量体（Ａ）は、分子中に複数個の上記酸性基を含有してもよい。本発明の着色樹脂粒子は、共重合成分として酸性単量体（Ａ）を用いることで、粒子自身の表面が負荷電に発現する事ができ、非水系溶媒中に分散された粒子の分散安定性が向上する。　酸性単量体（Ａ）は、単量体（Ｍ）の総量に対して、好ましくは１〜４５重量％、より好ましくは３〜３０重量％で用いる。
【００６６】
以下に、酸性単量体（Ａ）の具体例を示す。本発明はこれらに限定されるものではない（但し下記具体例中、Ｙは−ＳＯ_３Ｈ基及び−ＳＯ_２Ｈ基又は−ＰＯ_３Ｈ_２又は−ＯＰＯ_３Ｈ_２基を表す）。
【００６７】
【化７】

【００６８】
【化８】

【００６９】
本発明では、単量体（Ｍ）と共重合可能な、長鎖の脂肪族基を有する単量体（Ｌ）を更に併用してもよい。長鎖の脂肪族基を有する単量体（Ｌ）において、長鎖の脂肪族基は炭素数７以上の脂肪族基を表す。その場合の具体例としては、総炭素数１０〜３２の脂肪族基（脂肪族基はハロゲン原子、ヒドロキシル基、アミノ基、アルコキシ基等の置換基を含有していてもよく、または酸素原子、イオウ原子、窒素原子等のヘテロ原子でその主鎖の炭素−炭素結合が介されてもよい）を有するアクリル酸、α−フルオロアクリル酸、α−クロロアクリル酸、α−シアノアクリル酸、メタクリル酸、クロトン酸、マレイン酸、イタコン酸の如き不飽和カルボン酸のエステル類（脂肪族基として、例えばデシル基、ドデシル基、トリデシル基、テトラデシル基、ヘキサデシル基、オクタデシル基、ドコシル基、ドデセニル基、ヘキサデセニル基、オレイル基、リノレイル基、ドコセニル基等が挙げられる）；上記不飽和カルボン酸のアミド類（脂肪族基として、上記エステル類で示したと同様のものが挙げられる）；高級脂肪酸のビニルエステル類あるいはアリルエステル類（高級脂肪酸として、例えば、ラウリン酸、ミリスチン酸、ステアリン酸、オレイン酸、リノール酸、べヘン酸等が挙げられる）；及び総炭素数８〜３２の脂肪族基が酸素原子に結合したビニルエーテル類（脂肪族基としては、上記の不飽和カルボン酸エステル類で例示した脂肪族基と同じものが挙げられる）等を挙げることができる。
【００７０】
長鎖の脂肪族基を有する単量体（Ｌ）を用いることにより、着色樹脂粒子の分散安定性、再分散性が更に向上する。これは単量体（Ｌ）に相当する共重合成分が、溶媒との親媒和性が高いことで粒子表面部分に配向し、そのことで粒子自身の表面の溶媒との親媒和性が高まり、粒子同志の凝集・沈殿を抑制するためと推定される。単量体（Ｌ）を用いる場合の使用量は、全単量体中、０．５〜２０重量％、好ましくは１〜１５重量％である。
【００７１】
次に分散安定化剤（Ｐ）について説明する。
分散安定化剤（Ｐ）は、該非水溶媒に可溶であって、一般式（Ｉ）で示される該非水溶媒に可溶性の重合体成分Ａと、一般式（ＩＩ）で示される重合体繰返し成分の置換基の末端に重合性二重結合基を有する重合体成分Ｂとを主成分とする。
重合体成分Ａを構成する一般式（Ｉ）で示される繰り返し単位において、Ｘ^０は、好ましくは−ＣＯＯ−、−ＯＣＯ−、−Ｏ−を表わす。
Ｑ^０は炭素数４〜２２の直鎖状或は分岐状のアルキル基又はアルケニル基を表す。具体的には、ブチル基、ヘプチル基、ヘキシル基、オクチル基、ドデシル基、トリデシル基、テトラデシル基、ヘキサデシル基、オクタデシル基、エイコサニル基、ヘキセニル基、オクテニル基、デセニル基、ドデセニル基、ヘキサデセニル基、オクタデセニル基、リノレル基等が挙げられる。
【００７２】
ａ^１とａ^２は、互いに同じでも異なってもよく、好ましくは水素原子、ハロゲン原子（例えば、塩素原子又は臭素原子等）、シアノ基、炭素数１〜３のアルキル基（例えば、メチル基、エチル基又はプロピル基等）、−ＣＯＯ−Ｚ^１又は炭化水素を介した−ＣＯＯ−Ｚ^１　（Ｚ^１は水素原子又は置換されてもよい炭化水素基を示す）を表す。Ｚ^１は水素原子又は炭素数１〜２２の、アルキル基、アルケニル基、アラルキル基、脂環式基、アリール基もしくは架橋環式炭化水素基を表わし、これらは置換されていてもよい。
【００７３】
Ｚ^１の好ましい炭化水素基としては、炭素数１〜２２の置換されてもよいアルキル基（例えば、メチル基、エチル基、プロピル基、ブチル基、ヘプチル基、ヘキシル基、オクチル基、ノニル基、デシル基、ドデシル基、トリデシル基、テトラデシル基、ヘキサデシル基、オクタデシル基、エイコサニル基、ドコサニル基、２−クロロエチル基、２−ブロモエチル基、２−シアノエチル基、２−メトキシカルボニルエチル基、２−メトキシエチル基、３−ブロモプロピル基等）、炭素数４〜１８の置換されてもよいアルケニル基（例えば、２−メチル−１−プロペニル基、２−ブテニル基、２−ペンテニル基、３−メチル−２−ペンテニル基、１−ペンテニル基、１−ヘキセニル基，２−ヘキセニル基、４−メチル−２−ヘキセニル基、デセニル基、ドデセニル基、トリデセニル基、ヘキサデセニル基、オクタデセニル基、リノレル基等）、　炭素数７〜１２の置換されてもよいアラルキル基（例えば、ベンジル基、フェネチル基、３−フェニルプロピル基、ナフチルメチル基、２−ナフチルエチル基、クロロベンジル基、ブロモベンジル基、メチルベンジル基、エチルベンジル基、メトキシベンジル基、ジメチルベンジル基、ジメトキシベンジル基等）、　炭素数５〜８の置換されてもよい脂環式基（例えば、シクロヘキシル基、２−シクロヘキシルエチル基、２−シクロペンチルエチル基等）、及び炭素数６〜１２の置換されてもよい芳香族基（例えば、フェニル基、ナフチル基、トリル基、キシリル基、プロピルフェニル基、ブチルフェニル基、オクチルフェニル基、ドデシルフェニル基、メトキシフェニル基、エトキシフェニル基、ブトキシフェニル基、デシルオキシフェニル基、クロロフェニル基、ジクロロフェニル基、ブロモフェニル基、シアノフェニル基、アセチルフェニル基、メトキシカルボニルフェニル基、エトキシカルボニルフェニル基、ブトキシカルボニルフェニル基、アセトアミドフェニル基、プロピオアミドフェニル基、ドデシロイルアミドフェニル基等）、又は炭素数５〜１８の架橋環式炭化水素基（例えば、ビシクロ〔１，１，０〕ブタン、ビシクロ〔３，２，１〕オクタン、ビシクロ〔５，２，０〕ノナン、ビシクロ〔４，３，２〕ウンデカン、アダマンタン等の基）が挙げられる。
【００７４】
重合体成分Ｂを構成する一般式（ＩＩ）で示される繰り返し単位において、Ｘ^１の好ましい例としては、−ＣＯＯ−、−ＯＣＯ−、−ＣＯＮ（Ｚ^２）−等が挙げられる。Ｘ^３の好ましい例としては、−ＣＯＯ−、−ＣＯＯ（ＣＨ_２）−、−Ｏ−等が挙げられる。
Ｗは結合基Ｘ^１と結合基Ｘ^３とを連結する基で、少なくとも１つの炭素原子、酸素原子、イオウ原子、ケイ素原子又は窒素原子からなるものを表し、その具体例を下記に示す。
【００７５】
【化９】

【００７６】
Ｇ^１、Ｇ^２は各々、水素原子、ハロゲン原子（例えば、フッ素原子、塩素原子、臭素原子等）、シアノ基、ヒドロキシル基、アルキル基（例えば、メチル基、エチル基、プロピル基等）等を示す。
Ｇ^３、Ｇ^４、Ｇ^５は各々、水素原子、炭素数１〜８の炭化水素基（例えば、メチル基、エチル基、プロピル基、ブチル基、ペンチル基、ヘキシル基、ベンジル基、フェネチル基、フェニル基、トリル基等）または−ＯＧ^５（Ｇ^５は、Ｇ^３における炭化水素基と同義である）を表す）等が挙げられる。
【００７７】
本発明の分散安定化剤（Ｐ）の構成成分である、一般式（Ｉ）で示される該非水溶媒に可溶性の重合体成分Ａと、一般式（ＩＩ）で示される重合体繰返し成分の置換基の末端に重合性二重結合基を有する重合体成分Ｂの好ましい例を以下に挙げる。更に本発明の分散安定化剤（Ｐ）の好ましい例も以下に挙げるが、本発明の範囲はこれに限定されるものではない。
【００７８】
【化１０】

【００７９】
【化１１】

【００８０】
【化１２】

【００８１】
【化１３】

【００８２】
本発明の分散安定化剤（Ｐ）は、従来公知の合成方法によって容易に合成することができる。
即ち、一般式（Ｉ）で示される重合体成分Ａに相当する単量体と、一般式（ＩＩ）で示される重合体成分Ｂに相当し、ラジカル重合反応における重合反応性が異なる二官能性単量体を用いて、特開昭６０−１８５９６２号公報記載の方法等により重合反応させることにより、ゲル化反応を生じることなく合成する事ができる。
【００８３】
また、樹脂中に重合性二重結合基を導入する方法としては、特開昭６１−４３７５７号公報記載の方法等により合成する事ができる。具体的には、一般式（ＩＩ）で示される重合体成分Ｂにおいて、重合性二重結合基：−Ｘ^３−Ｃ（ｃ^１）＝ＣＨ（ｃ^２）の代わりに、予め特定の反応性基（例えば−ＯＨ、−ＣＯＯＨ、−ＳＯ_３Ｈ、−ＮＨ_２、−ＳＨ、−ＰＯ_３Ｈ_２、−ＮＣＯ、−ＮＣＳ、−ＣＯＣｌ、−ＳＯ_２Ｃｌ、エポキシ基等）を含有した単量体を、一般式（Ｉ）で示される重合体成分Ａに相当する単量体と、ともに重合反応させた後に、上記の重合性二重結合基を含有する反応性試薬を反応させて、高分子反応により重合性二重結合基を導入する方法が挙げられる。
【００８４】
分散安定化剤（Ｐ）において、重合性二重結合基を有する一般式（ＩＩ）で示される重合体成分Ｂの存在割合は、全重合体１００重量部中において、通常０．５〜３０重量％であり、好ましくは１〜１０重量％である。この範囲内において、重合造粒反応時において、反応混合物の架橋反応によるゲル化は起こらず、重合性二重結合基を有する分散安定化剤（Ｐ）を得ることができる。
【００８５】
また、本発明に供される分散安定化剤（Ｐ）は、一般式（Ｉ）、（ＩＩ）の各繰り返し単位とともに、他の繰り返し単位を共重合成分として含有してもよい。他の共重合成分としては、一般式（Ｉ）、（ＩＩ）の各々の繰り返し単位に相当する単量体と共重合可能な単量体よりなるものであればいずれの化合物でもよい。
【００８６】
本発明の分散安定化剤（Ｐ）の重量平均分子量（Ｍｗ）は、５×１０^３〜１×１０^６が好ましく、より好ましくは２×１０^４〜３×１０^５である。
【００８７】
本発明で用いられる着色剤を内包した着色樹脂粒子を製造するには、非水溶媒中に表面処理された着色成分を微粒子状に分散させシード粒子とした中で、単量体と重合体繰返し成分の置換基の末端に重合性二重結合基を有する分散安定化剤（Ｐ）を加えた重合系を、過酸化ベンゾイル、アゾビス（２，４−ジメチルバレロニトリル）、アゾビス（４−メトキシ−２，４−ジメチルバレロニトリル）、アゾビスイソブチロニトリル又はブチルリチウム等の重合開始剤の存在下に重合させればよい。
【００８８】
非水溶媒中に表面処理された着色成分を微粒子状に分散させシード粒子とした中に、単量体と重合体繰返し成分の置換基の末端に重合性二重結合基を有する分散安定化剤（Ｐ）と重合開始剤とを具体的に加えるには、
（１）単量体と分散安定化剤（Ｐ）と重合開始剤とを非水溶媒中に混合溶解した溶液を滴下する方法、もしくは一括あるいは分割して添加する方法、
（２）非水溶媒中に着色成分を微粒子状に分散させシード粒子とした中に分散安定化剤（Ｐ）を溶解した溶液を加え、次に単量体と重合開始剤とを滴下、もしくは一括あるいは分割して添加する方法、
（３）非水溶媒中に着色成分を微粒子状に分散させシード粒子とした中に、単量体、分散安定化剤（Ｐ）、重合開始剤を非水溶媒中に混合溶解した溶液の一部を加え分散重合させた後に、残りの単量体、分散安定化剤（Ｐ）、重合開始剤の混合物を任意に添加する方法、
（４）非水溶媒中に着色成分を微粒子状に分散させシード粒子とした中に単量体の一部を加えてシード粒子へのモノマー吸収を促進させ、次に残りの単量体、分散安定化剤（Ｐ）と重合開始剤とを滴下、もしくは一括あるいは分割して添加する方法
等があり、いずれの方法を用いても製造することができる。
【００８９】
次に着色剤を内包した着色樹脂粒子を形成する各成分の量について説明する。シード粒子（着色成分微粒子）と単量体｛（Ｍ）並びに、必要に応じて（Ｂ）、（Ａ）及び／又は（Ｌ）｝の総量との使用割合は、５／９５〜９５／５重量比が好ましく、より好ましくは１０／９０〜８０／２０重量比である。単量体総量の仕込み量は、非水溶媒１００重量部に対して５〜８０重量部程度であり、好ましくは１０〜５０重量部である。可溶性もしくはコロイド状に分散している、重合体繰返し成分の置換基の末端に重合性二重結合基を有する分散安定化剤（Ｐ）は、上記で用いる全単量体１００重量部に対して１〜１００重量部であり、好ましくは３〜５０重量部である。重合開始剤の量は、全単量体の０．１〜５モル％が適切である。又、重合温度は２０〜１８０℃程度であり、好ましくは３０〜１２０℃である。反応時間は１〜１５時間が好ましい。
【００９０】
反応に用いた非水溶媒中に、トルエン、キシレン等の芳香族炭化水素が残存する場合、及び前記したアルコール類、ケトン類、エーテル類、エステル類等の極性溶媒を併用した場合、あるいは重合造粒化される単量体の未反応物が残存する場合、該溶媒あるいは単量体の沸点以上に加温して留去するかあるいは減圧留去することによって除くことが好ましい。
【００９１】
以上の如くして製造された非水系顔料内包樹脂粒子は、着色剤が均一に微粒子分散され、且つ分散液の分散安定性に優れることにより、ノズル部での目詰まりが起きない吐出安定性の高いインクジェットプリンタ用油性インクを提供する。また記録紙上での乾燥性、記録画像の耐水性、耐光性に優れており、且つ高度の耐擦過性を有する。更に、非水系溶媒中で均一に微粒子分散された着色剤内包樹脂粒子を容易に得ることができ、荷電極性の制御、荷電の経時安定性に優れたインクジェットプリンタ用油性顔料インク、及びその安価な製造方法を提供する。また、単量体を適切に選択する事により、定着性、荷電性などの機能を着色剤内包樹脂粒子に導入することができる特徴を有する。
【００９２】
本発明のインク組成物には、所望により各種添加剤を加えてもよい。インクジェット方式あるいはインクジェット吐出ヘッド、インク供給部、インク循環部の材質・構造等によって、任意に選択されインク組成物として含有される。
例えば、甘利武司監修「インクジェットプリンタ−技術と材料」第１７章、（株）シーエムシー刊（１９９８年）等に記載されている。
【００９３】
具体的には、脂肪酸類（例えば、炭素数６〜３２のモノカルボン酸、多塩基酸；例えば、２−エチルヘキシン酸、ドデセニルコハク酸、ブチルコハク酸、２−エチルカプロン酸、ラウリル酸、パルミチン酸、エライジン酸、リノレイン酸、リシノール酸、オレイン酸、ステアリン酸、エナント酸、ナフテン酸、エチレンジアミン四酢酸、アビエチン酸、デヒドロアビエチン酸、水添ロジン等）、樹脂酸、アルキルフタル酸、アルキルサリチル酸等の金属塩（金属イオンの金属としては、Ｎａ、Ｋ、Ｌｉ、Ｂ、Ａｌ、Ｔｉ、Ｃａ、Ｐｂ、Ｍｎ、Ｃｏ、Ｚｎ、Ｍｇ、Ｃｅ、Ａｇ、Ｚｒ、Ｃｕ、Ｆｅ、Ｂａ等）、界面活性化合物類（例えば、有機リン酸又はその塩類として、炭素数３〜１８のアルキル基から成るモノ、ジ又はトリアルキルリン酸等、有機スルホン酸又はその塩類として、長鎖脂肪族スルホン酸、長鎖アルキルベンゼンスルホン酸、ジアルキルスルホコハク酸等又はその金属塩、両性界面活性化合物として、レシチン、ケファリン等のリン脂質等が挙げられる）、フッ素原子及び／又はジアルキルシロキサン結合基を含有するアルキル基含有の界面活性剤類、脂肪族アルコール類（例えば、炭素数９〜２０の分岐状アルキル基から成る高級アルコール類、ベンジルアルコール、フェネチルアルコール、シクロヘキシルアルコール等）、多価アルコール類｛例えば、炭素数２〜１８のアルキレングリコール（エチレングリコール、１，２−プロピレングリコール、１，３−プロピレングリコール、１，４−ブタンジオール、ネオペンチルグリコール、１，６−ヘキサンジオール、ドデカンジオールなど）｝；炭素数４〜１０００のアルキレンエーテルグリコール（ジエチレングリコール、トリエチレングリコール、ジプロピレングリコール、ポリエチレングリコール、ポリプロピレングリコール、ポリテトラメチレンエーテルグリコールなど）；炭素数５〜１８の脂環式ジオール（１，４−シクロヘキサンジメタノール、水素添加ビスフェノールＡなど）；炭素数１２〜２３のビスフェノール類（ビスフェノールＡ、ビスフェノールＦ、ビスフェノールＳなど）の炭素数２〜１８のアルキレンオキサイド（エチレンオキサイド、プロピレンオキサイド、ブチレンオキサイド、α−オレフィンオキサイドなど）付加物、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、ペンタエリスリトール、ソルビトール等のポリオール類；３価〜８価またはそれ以上のフェノール類（トリスフェノールＰＡ、フェノールノボラック、クレゾールノボラックなど）；上記３価以上のポリフェノール類の炭素数２〜１８のアルキレンオキサイド付加物（付加モル数は２〜２０）、上記多価アルコールのエーテル誘導体（ポリグリコールアルキルエーテル類、アルキルアリールポリグリコールエーテル等）、多価アルコールの脂肪酸エステル誘導体、多価アルコールのエーテルオレート誘導体（例えば、エチレングリコールモノエチルアセテート、ジエチレングリコールモノブチルアセテート、プロピレングリコールモノブチルプロピオレート、ソルビタンモノメチルジオキサノレート等）、アルキルナフタレンスルホネート、アルキルアリールスルホネート等の化合物が挙げられるが、これらに限定されるものではない。
【００９４】
各種添加剤の使用量は、インク組成物の表面張力が１５〜６０ｍＮ／ｍ（２５℃において）及び粘度が１．０〜４０ｃｐの範囲となるように調整して用いることが好ましい。
【００９５】
また、本発明の液体現像剤には、荷電特性の強化あるいは画像特性の改良等のために、所望により種々の荷電調節剤を加えても良い。
【００９６】
本発明において使用する液体現像剤用の荷電調節剤としては従来、公知のものを使用することができる。例えばナフテン酸、オクテン酸、オレイン酸、ステアリン酸等の脂肪酸の金属塩、スルホコハク酸エステルの金属塩、特公昭４５−５５６号、特開昭５２−３７４３５号、特開昭５２−３７０４９号の各公報等に示されている油溶性スルホン酸金属塩、特公昭４公報に示されているリン酸エステル金属塩、特公昭４８−２５６６６号公報に示されているアビエチン酸もしくは水素添加アビエチン酸の金属塩、特公昭５５−２６２０号公報に示されているアルキルベンゼンスルホン酸Ｃａ塩類、特開昭５２−１０７８３７号、同５２−３８９３７号、同５７−９０６４３号、同５７−１３９７５３号の各公報に示されている芳香族カルボン酸あるいはスルホン酸の金属塩類、ポリオキシエチル化アルキルアミンのような非イオン性界面活性剤、レシチン、アマニ油等の油脂類、ポリビニルピロリドン、多価アルコールの有機酸エステル、特開昭５７−２１０３４５号公報に示されているリン酸エステル系界面活性剤、特公昭５６−２４９４４号公報に示されているスルホン酸樹脂等を使用することができる。また特開昭６０−２１０５６号、同６１−５０９５１号の各公報に記載されたアミノ酸誘導体も使用することができる。また特開昭６０−１７３５５８号、同６０−１７９７５０号の各公報に記載されているマレイン酸ハーフアミド成分を含む共重合体等が挙げられる。さらに特開昭５４−３１７３９号、特公昭５６−２４９４４号の各公報等に示されている４級化アミンポリマーを挙げることが出来る。
【００９７】
これらの内で好ましいものとしては、ナフテン酸の金属塩、ジオクチルスルホコハク酸の金属塩、前記マレイン酸ハーフアミド成分を含む共重合体、レシチン、前記アミノ酸誘導体を挙げることができる。これらの荷電調節剤としては、２種以上の化合物を併用することも可能である。
上述の様な荷電調節剤は、非水溶媒１０００重量部に対して０．００１重量部〜１０．０重量部が好ましい。更に所望により各種添加剤を加えても良く、それら添加物の総量は、現像剤の電気抵抗によってその上限が規制される。即ち、トナー粒子を除去した状態の液体現像剤の電気抵抗が１０^９Ωｃｍより低くなると良質の連続階調像が得られ難くなるので、各添加物の各添加量を、この限度内でコントロールすることが必要である。
【００９８】
以下の実施例で、本発明のインク組成物がインクジェットプリンタ用油性インクとして有用な事を示す。インクジェットプリンタとしては、ピエゾ方式及び静電方式のインクジェットプリンタを例にして説明するが、これらの方式に限定されずに、サーマル方式やＮＴＴなどのスリットジェットに代表されるインクジェットプリンタにも適用できる。
【００９９】
静電方式のインクジェットプリンタについて更に説明する。
図１及び図２は吐出ヘッドの例を説明する概略図で、図１はライン走査型マルチチャンネルインクジェットヘッドの構成を示す図で、記録ドットに対応した吐出電極の断面を示している。同図においてインク１００はポンプを含む循環機構１１１から、ヘッドブロック１０１に接続されたインク供給流路１１２を通して、ヘッド基板１０２と吐出電極基板１０３間に供給され、同じくヘッドブロック１０１に形成されたインク回収流路１１３を通してインク循環機構１１１に回収される。この吐出電極基板１０３は、貫通孔１０７を有する絶縁性基板１０４と、この貫通孔１０７の周囲で記録媒体側に形成されている吐出電極１０９とから構成されている。一方ヘッド基板１０２上には凸状インクガイド１０８が前記貫通孔１０７の略中心位置に配置されている。この凸状インクガイド１０８はプラスチック樹脂、セラミックスなど絶縁性部材からなり、前記貫通孔１０７と中心が等しくなるように同じ列間隔、ピッチで配置され、所定の方法でヘッド基板１０２上に保持されている。各凸状インクガイド１０８は厚みが一定の平板の先端を三角形あるいは台形状に切り出した形状で、その先端部がインク滴飛翔位置１１０となる。各凸状インクガイド１０８はその先端部からスリット状の溝を形成しても良く、そのスリットの毛細管現象により、インク飛翔位置１１０へのインク供給がスムースに行われ、記録周波数を向上することが出来る。またインクガイドの任意の表面は必要に応じて導電性を有していても良く、その場合には導電部分は電気的に浮遊状態とする事によって、吐出電極への少ない電圧印加で有効にインク飛翔位置に電界を形成できる。各凸状インクガイド１０８は、それぞれの貫通孔からほぼ垂直に所定の距離だけインク滴飛翔方向に突きだしている。凸状インクガイド１０８の先端に対向して記録紙である記録媒体１２１が配置され、この記録媒体１２１のヘッド基板１０２と反対側の背面に、記録媒体１２１を案内するプラテンの役割を兼ねる対向電極１２２が配置されている。また、ヘッド基板１０２と吐出電極基板１０３間によって形成される空間の底部には泳動電極１４０が形成されており、これに所定の電圧を印加する事により、インクガイドの吐出位置方向にインク中の荷電粒子を電気泳動させ、吐出の応答性を上げることが出来る。
【０１００】
次に、吐出電極基板１０３の具体的構成例について図２を用いて説明する。図２は、吐出電極基板１０３を記録媒体１２１側から見た図で、複数個の吐出電極が主走査方向に二列でアレイ状に配列されて、各吐出電極の中心に貫通孔１０７が形成され、この貫通孔１０７の周辺にはそれぞれ個別の吐出電極１０９が形成されている。本実施例では吐出電極１０９の内径は貫通孔１０７の径より一回り大きく設けられているが、貫通孔１０７の径と同径でも良い。ここでは、絶縁性基板１０４は２５から２００μｍ程度の厚さのポリイミドからなり、吐出電極１０９は１０から１００μｍ程度の厚さの銅箔からなり、貫通孔１０７の内径は１５０から２５０μｍΦ程度である。
【０１０１】
次に、静電方式のインクジェット記録装置の記録動作を説明する。ここでは正荷電したインクを用いた場合を例にとって説明するが、本発明は本例に限定される物ではない。記録時には、インク循環機構１１１からインク供給流路１１２を経て供給されたインク１００は貫通孔１０７から凸状インクガイド１０８の先端のインク飛翔位置１１０に供給されると共に、一部はインク回収流路１１３を経てインク循環機構１１１に回収される。ここで、吐出電極１０９にはバイアス電圧源１２３から常時バイアスとして例えば＋１．５ｋＶの電圧が与えられ、これに信号電圧源１２４からの画像信号に応じた信号電圧として例えばＯＮ時に＋５００Ｖのパルス電圧が吐出電圧１０９に重畳される。またこの際、泳動電極１４０は＋１．８ｋＶの電圧が印加されている。一方、記録媒体１２１の背面に設けられた対向電極１２２は、図のように接地電圧０Ｖに設定されている。場合によっては記録媒体１２１側を例えば−１．５ｋＶに帯電させてバイアス電圧としても良い。この場合には、対向電極１２２表面に絶縁層を設け、記録媒体にコロナチャージャー、スコロトロンチャージャー、固体イオン発生器等により帯電を行い、かつ吐出電極１０９は例えば接地され、これに信号電圧源１２４からの画像信号に応じた信号電圧として例えばＯＮ時に＋５００Ｖのパルス電圧が吐出電圧１０９に重畳される。またこの際、泳動電極１４０は＋２００Ｖの電圧が印加される。今、吐出電圧１０９がＯＮ状態（５００Ｖが印加された状態）となり、バイアスＤＣ１．５ｋＶに５００Ｖのパルス電圧が重畳された合計２ｋＶの電圧が加わると、凸状電極１０８先端のインク滴飛翔位置１１０から、インク滴１１５が飛び出し、対向電極１２２方向に引っ張られて、該記録媒体１２１に向けて飛翔して画像を形成する。
【０１０２】
なお、飛翔後のインク液滴の飛翔を精密制御し記録媒体上での着弾精度を向上するため、吐出電極と記録媒体間に中間電極を設ける、あるいは吐出電極間に電界干渉抑制用のガード電極を設ける、等の手段がしばしば講じられるが、本実施例においても必要により好適に使用されることはもちろんである。また、ヘッド基２８板１０２と吐出電極基板１０３間に多孔質体を設けても良く、この場合にはインクジェットヘッドの移動等によるインク内圧の変化の影響を防止できると共にインク滴吐出後の貫通孔１０７部へのインク液供給が迅速に達成される。したがって、インク滴１１５の飛翔が安定化され、記録媒体１２１上に濃度の安定した良好な画像を高速に記録することができる。
【０１０３】
【実施例】
以下、本発明の実施例を説明する。
分散安定化剤の合成例１：（Ｐ−１）の合成（化合物例（ａ））
ラウリルメタクリレート９６．７ｇ、ビニルメタクリレ−ト２．２ｇ、及びイソデカン４００ｇの混合溶液を窒素気流下、温度７０℃に加温した。攪拌下、２，２’−アゾビス（ブチロニトリル）１．０ｇを添加し、３時間反応させ、さらに２，２’−アゾビス（ブチロニトリル）１．０ｇを添加して、４時間反応させた。得られた溶液の固形分濃度は１９％であった。
上記反応溶液の１部をその１０倍量のメタノール溶媒中へ投入して得た無色透明な粘稠物の高速液体クロマトグラフ法で測定した重量平均分子量は３．８×１０^４であった。
【０１０４】
分散安定化剤の合成例２：（Ｐ−２）の合成（化合物例（ｂ））
ステアリルメタクリレート１２８．７ｇ、ビニルメタクリレ−ト２．２ｇ、及びイソデカン３００ｇの混合溶液を窒素気流下、温度７５℃に加温した。その後、２，２’−アゾビス（ブチロニトリル）１．３ｇを添加し、３時間攪拌した。さらに２，２’−アゾビス（ブチロニトリル）１．３ｇを添加して、５時間反応させた。得られた溶液の固形分濃度は３０．０％であった。合成例１の如く処理し測定した白色固体の得られた重量平均分子量は３．５×１０^４であった。
【０１０５】
分散安定化剤の合成例３：（Ｐ−３）の合成（化合物例（ｃ））
ラウリルメタクリレート７１．０ｇ、ビニルオキシカルボニルメチルオキシ・カルボニルエチルアクリレート２．２ｇ、及びイソデカン２９３ｇの混合溶液を窒素気流下、温度７０℃に加温した。その後、２，２’−アゾビス（ブチロニトリル）１．１ｇを添加し、３時間攪拌した。さらに２，２’−アゾビス（ブチロニトリル）１．１ｇを添加して、５時間反応させた。得られた溶液の固形分濃度は１９．６％であった。合成例１の如く処理し測定した白色固体の得られた重量平均分子量は３．５×１０^４であった。
【０１０６】
分散安定化剤の合成例４：（Ｐ−４）の合成（化合物例（ｈ））
ヘキサデシルアクリレート５９．０ｇ、アリルオキシカルボニルデカメチレンメタクリルアミド３．１ｇ、及びｎ−ドデカン１４５ｇの混合溶液を窒素気流下、温度７５℃に加温した。その後、２，２’−アゾビス（ブチロニトリル）０．９ｇを添加し、３時間攪拌した。さらに２，２’−アゾビス（ブチロニトリル）０．９ｇを添加して、４時間反応させた。得られた溶液の固形分濃度は２９．４％であった。合成例１の如く処理し測定した白色固体の得られた重量平均分子量は４．１×１０^４であった。
【０１０７】
分散安定化剤の合成例５：（Ｐ−５）の合成（化合物例（ｉ））
ステアリルメタクリレート４５．０ｇ、ビニルオキシエチルアクリレート１．７ｇ、及びアイソパーＧを１０９ｇの混合溶液を窒素気流下、温度７５℃に加温した。その後、過酸化ベンゾイル０．７ｇを添加し、３時間攪拌した。さらに過酸化ベンゾイル０．７ｇを添加して、４時間反応させた。得られた溶液の固形分濃度は２９．０％であった。合成例１の如く処理し測定した白色固体の得られた重量平均分子量は３．８×１０^４であった。
【０１０８】
分散安定化剤の合成例６〜１２：（Ｐ−６）〜（Ｐ−１２）の合成
下記表−Ａに記載の各単量体を所定量、及びアイソパーＧを２５０ｇの混合溶液を窒素気流下、温度６５℃に加温した。その後、２，２’−アゾビス（ブチロニトリル）１．０ｇを添加し、４時間反応させ、さらに２，２’−アゾビス（ブチロニトリル）０．５ｇを添加して、３時間反応させた。冷却後、メタノール溶媒２Ｌ中へ投入して再沈し、得られた沈殿物をろ過、室温で減圧乾燥した。得られた各樹脂の重量平均分子量は４．０×１０^４〜８．０×１０^４であった。
【０１０９】
【表１】

【０１１０】
分散安定化剤の合成例１３：（Ｐ−１３）の合成（化合物例（ｌ））
ラウリルメタクリレート９６．７ｇ、ヒドロキシカルボニルデカメチレンメタクリルアミド５．４ｇ、及びトルエン１００ｇの混合溶液を窒素気流下、温度７０℃に加温し、攪拌下に２，２’−アゾビス（ブチロニトリル）１．０ｇを添加した。６時間後に４０℃まで冷却し０．２ｇのハイドロキノンを添加した。更に酢酸ビニル６．９ｇ、酢酸水銀０．０５ｇを加えて２時間反応させた。温度を再び７０℃に上げ、１００％硫酸７．５ｘ１０^−３モル添加し前記メタクリルアミドモノマー化合物に由来するカルボン酸定量値が５０％に減少するまで反応を行った。反応後、反応液に０．０４ｇの酢酸ナトリウム三水和物を添加してよく攪拌してから４０００ｇのメタノールに投入して再沈精製し、やや褐色を帯びた粘稠物を得た。この粘稠物の重量平均分子量は１４．５×１０^４であった。
【０１１１】
分散安定化剤の合成例１４：（Ｐ−１４）の合成（化合物例（ｋ））
合成例１３において用いた、ラウリルメタクリレートの代わりにステアリルメタクリレート１２８．６ｇを用いて、合成例１３と同様の操作を行い、やや黄色味を帯びた粉末物を得た。この粉末物の重量平均分子量は２２．２×１０^４であった。
【０１１２】
分散安定化剤の合成例１５：（Ｐ−１５）の合成（化合物例（ｍ））
ラウリルアクリレート８７．５ｇ、ヒドロキシカルボニルデカメチレンメタクリルアミド９．７ｇ、及びアイソパーＥを１２０ｇの混合溶液を窒素気流下、温度８０℃に加熱し、攪拌下に２，２’−アゾビス（ブチロニトリル）１．０ｇを添加した。３時間後に再び２，２’−アゾビス（ブチロニトリル）１．０ｇを添加し３時間反応させた。０．２ｇのハイドロキノンを添加してから、同温度で酢酸ビニル１１．４ｇ、テトラブトキシチタン１．０ｇを加えて前記メタクリルアミドモノマー化合物に由来するカルボン酸定量値が５０％に減少するまで反応を行った。反応後、４０００ｇのアセトニトリルより再沈精製し、やや褐色を帯びた粘稠物を得た。重量平均分子量は１０．３×１０^４であった。
【０１１３】
分散安定化剤の合成例１６：（Ｐ−１６）の合成（化合物例（ｏ））
ステアリルメタクリレート１３７．１ｇ、ヒドロキシカルボニルトリメチレンオキシ・カルボニルエチルメタクリレート１１．０ｇ、及びトルエン３００ｇの混合溶液を窒素気流下、温度７０℃に加熱し、攪拌下に２，２’−アゾビス（ブチロニトリル）１．５ｇを添加した。６時間後に４０℃まで冷却し０．５ｇのハイドロキノンを添加した。更に酢酸ビニル３１．０ｇ、酢酸水銀０．２ｇを加えて２時間反応させた。温度を再び７０℃に上げ１００％硫酸３．４×１０^−２モル添加し前記酸含有メタクリレートモノマー化合物に由来するカルボン酸定量値が３５％に減少するまで反応を行った。反応後、反応液に０．２ｇの酢酸ナトリウム三水和物を添加してよく攪拌してから合成例１３と同様にして再沈精製し、白色粉末物を得た。重量平均分子量は２９．５×１０^４であった。
【０１１４】
分散安定化剤の合成例１７：（Ｐ−１７）の合成（化合物例（ｎ））
ヘキサデシルメタクリレート１０５．６ｇ、ヒドロキシカルボニルトリメチレンオキシ・カルボニルエチルメタクリレート６．７ｇ、及びアイソパーＥ２００ｇの混合溶液を窒素気流下、温度７０℃に加熱し、攪拌下に２，２’−アゾビス（ブチロニトリル）１．６ｇを添加した。６時間後に４０℃まで冷却し０．２ｇのハイドロキノンを添加した。更に酢酸ビニル２５．０ｇ、テトラブトキシチタン３ｇを加えて温度を再び７０℃に上げ、前記酸含有メタクリレートモノマー化合物に由来するカルボン酸定量値が５０％に減少するまで反応を行った。反応後、合成例１３と同様にして再沈精製し、やや黄色味を帯びた粘稠物を得た。重量平均分子量は２８．７×１０^４であった。
【０１１５】
分散安定化剤の合成例１８：（Ｐ−１８）の合成（化合物例（ｐ））
ヘキサデシルメタクリレート１０５．６ｇ、ヒドロキシカルボニルデカメチレンメタクリルアミド６４．７ｇ、及びアイソパーＥ４００ｇの混合溶液を窒素気流下、温度８０℃に加温し、攪拌下に２，２’−アゾビス（ブチロニトリル）１．６ｇを添加した。６時間後に０．１ｇのハイドロキノンを添加してから、温度を１１０℃に上げアリルアルコール５８．１ｇ、濃硫酸０．５ｇを加え、ディーンスタークの装置で留出する水分を除去しながら反応させた。前記メタクリルアミドモノマー化合物に由来するカルボン酸定量値が３５％に減少したところで反応を停止し、合成例１３と同様にして再沈精製し、やや茶色味を帯びた粘稠物を得た。重量平均分子量は１９．７×１０^４であった。
【０１１６】
実施例１
＜顔料分散液の調製＞
下記構造の顔料分散剤（Ｄ−１）をアイソパーＨに加熱溶解して調液した２０％溶液を、顔料分散剤として用いた。上記顔料分散剤溶液８８．２５重量部と、黒色加工顔料としてロジンエステル樹脂で処理されたマイクロリスブラックＣ−Ｔ（チバ・スペシャリティ・ケミカルズ社製）１７．６５重量部、アイソパーＨ２９．４重量部及びガラスビーズ２５０重量部とともにペイントシェイカー（東洋精機ＫＫ）で３０分間混合した。次にガラスビーズをろ別した後、高速度分散混和機器ダイノミル（商品名；ＫＤＬ）で回転数３０００ｒｐｍで３時間分散した。メディアはガラスビーズＭＫ−３ＧＸを使用した。分散液中の顔料粒子の体積平均粒径を、超遠心式自動粒度分布測定装置ＣＡＰＡ７００（堀場製作所）にて測定した所、０．１６μｍと良好に分散されていた。
【０１１７】
【化１４】

【０１１８】
＜着色樹脂粒子の調製＞
ガラスビーズをろ過した加工顔料分散液のろ液（固形分２３．３％）８５．８ｇを四つ口フラスコに入れ窒素気流下攪拌しながら温度８０℃で３時間加熱した。
次にこの加工顔料分散液中に、分散安定化剤（Ｐ）として（Ｐ−１）を粉体で８ｇ、メタクリル酸メチル１２．０ｇ、アクリル酸メチル２８．０ｇ及びアイソパーＨ１２０ｇの混合溶液に２，２′−アゾビス（２，４−ジメチルバレロニトリル）１．０ｇを加えた溶液をフィード溶液として、滴下速度２．５ｍｌ／分で滴下しその後３時間反応させた。滴下開始から約２０分して発熱が始まり、反応液温度は約５℃程上昇した。３時間反応後に温度を９０℃に上げ２時間攪拌し未反応のモノマーを留去した。冷却後２００メッシュのナイロン布を通し得られた黒色樹脂粒子分散液は重合率９７％でその体積平均粒子サイズは０．２４μｍであった。得られた黒色樹脂粒子分散液は、１カ月静置保存した後の分散状態も良好であった。
黒色樹脂粒子分散液をＳ−８００形電界放射形走査電子顕微鏡（日立電気社製）で観察した所、約１００ｎｍ程度のマイクロリスブラック顔料粒子が分散重合後には約１８０ｎｍの球形状樹脂粒子に成長しており、滴下モノマーがシード顔料粒子内で吸収され重合していることが判った。
更に黒色粒子分散液を透過形走査電子顕微鏡で観察した所、分散重合後の約１８０ｎｍの球形状着色樹脂粒子の中にはシードの顔料粒子が内包されているのが判った。
以上より、本発明のシード分散重合により生成した着色樹脂粒子は、ロジンエステル樹脂処理された顔料を内部に含有した着色樹脂粒子である事が判る。
【０１１９】
＜インク組成物（ＩＪ−１）の作製＞
上記着色樹脂粒子分散液を、溶媒留去により一旦濃縮しアイソパーＧにて希釈する事により、粘度は１３ｃｐ（Ｅ型粘度計、温度２５℃で測定）、表面張力は２３ｍＮ／ｍ（協和界面科学社製の自動表面張力計、温度２５℃で測定）のインク組成物（ＩＪ−１）を調液した。インクジェット記録装置としてカラーファクシミリ彩遊記ＵＸ−Ｅ１ＣＬ（シャープ社製）を用い、上記インク組成物（ＩＪ−１）を充填して、富士写真フイルムインクジェットペーパーハイグレード専用紙上に描画した所、ノズル詰まりが無く安定に吐出した。得られた描画画像は、滲みがなく、画像濃度１．８の良質で明瞭なものであった。次にフルベタパターンを印字して、印字物を乾燥させた後ベタ部を指で擦ったところ、目視で地汚れが全くなく極めて耐擦過性に優れていることが判った。インク組成物は、長期に保存しても沈降凝集が見られず分散性が極めて良好で、かなりな期間連続して印刷に使用でき優れた鮮明度の印刷を与えた。
【０１２０】
実施例２
＜顔料分散物の調製＞
黒色顔料としてカーボンブラック＃３０（三菱化学社製）１００重量部、ポリマー処理の樹脂としてエチレン／ステアリルアクリレート共重合体（９５／５モル比）、２００重量部をトリオブレンダーで予備粉砕しよく混合した後に、１２０℃に加熱した三本ロールミルで溶融混練（２０分）した。上記の顔料混練物をピンミルで粉砕した。
次に顔料混練物１０重量部、アイソパーＨ６５重量部、下記構造の顔料分散剤（Ｄ−２）をアイソパーＨに加熱溶解して調液した２０ｗｔ％溶液を２０重量部、及び３Ｇ−Ｘガラスビーズ２５０重量部とともにペイントシェイカー（東洋精機ＫＫ）で６０分間混合した。次にガラスビーズをろ別した後、高速度分散混和機器ダイノミル（商品名；ＫＤＬ）で回転数３０００ｒｐｍで３時間分散した。メディアはガラスビーズＭＫ−３ＧＸを使用した。分散液中の顔料粒子の体積平均粒径を、超遠心式自動粒度分布測定装置ＣＡＰＡ７００（堀場製作所）にて測定した所、０．１６μと良好に分散されていた。
【０１２１】
【化１５】

【０１２２】
＜着色樹脂粒子の調製＞
ガラスビーズをろ過した顔料分散液のろ液（固形分１４．０％）２１４．３ｇを四つ口フラスコに入れ窒素気流下攪拌しながら温度７５℃で１時間加熱した。次にこの顔料分散液中に、実施例１と同様に、分散安定化剤（Ｐ−２）を粉体で４ｇ、メタクリル酸メチル６．０ｇ、アクリル酸メチル１４．０ｇ、及びアイソパーＨ８０ｇの混合溶液に２，２′−アゾビス（２，４−ジメチルバレロニトリル）０．５ｇを加えた溶液をフィード溶液として、一時間で滴下しその後３時間反応させた。滴下開始から約１５分して発熱が始まり、反応液温度は約４℃程上昇した。３時間反応後に温度を９０℃に上げ窒素流量を上げながら、２時間攪拌し未反応のモノマーを留去した。黒色樹脂粒子分散液は重合率９６．０％でその体積平均粒子サイズは０．２２μｍであった。得られた黒色樹脂粒子分散液は、１カ月静置保存した後の分散状態も良好であった。
【０１２３】
＜インク組成物（ＩＪ−２）の作製＞
上記着色樹脂粒子分散液を、溶媒留去により一旦濃縮しアイソパーＧにて希釈する事により、粘度は１３ｃｐ、表面張力は２３ｍＮ／ｍのインク組成物（ＩＪ−２）を調製した。インク組成物（ＩＪ−２）を、実施例１と同様にしてカラーファクシミリ彩遊記ＵＸ−Ｅ１ＣＬ（シャープ社製）で印刷した所、滲みのない良質の明瞭な印刷を与えた。また実施例１と同様にして耐擦過性を調べた所、目視で地汚れが全くなく極めて耐擦過性に優れていることが判った。インク組成物は、長期に保存しても沈降凝集が見られず分散性が良好であつた。
【０１２４】
実施例３
＜顔料分散物の調製＞
黒色顔料としてカーボンブラック＃１００（三菱化学社製）１０重量部、水１００重量部をフラッシャーで攪拌後、ポリマー処理の樹脂としてスチレン／ビニルトルエン／ラウリルメタクリリレート共重合体（４０／５８／２モル比）の３３％トルエン溶液６０重量部を、更にフラッシャーに加え攪拌した。次いで、加熱し減圧して水分と溶媒を除去して含水率１重量％の黒色塊状物を得た。黒色塊状物を真空乾燥し、水分を完全に除去した後、サンプルミルで粉砕し、０．１−０．０１ｍｍの黒色粉体を得た。実施例２において、顔料混練物の代わりに上記黒色粉体を用い、顔料分散剤として（Ｄ−２）の代わりに下記構造の顔料分散剤（Ｄ−３）を用いた他は、実施例２と全く同様に顔料分散を行った。ガラスビーズをろ別した後得られた黒色顔料分散液は、体積平均粒径が０．１３μｍと分散性は良好であった。
【０１２５】
【化１６】

【０１２６】
＜着色樹脂粒子の調製＞
ガラスビーズをろ過した顔料分散液のろ液（固形分１３．０％）をシード粒子として、実施例２において、分散安定化剤（Ｐ−１）の代わりに（Ｐ−３）を４ｇ用いた他は、実施例２と全く同様にして分散重合を行った。得られた黒色樹脂粒子分散液は重合率９８．０％でその体積平均粒子サイズは０．２３μｍであった。得られた黒色樹脂粒子分散液は、１カ月静置保存した後の分散状態も良好であった。
【０１２７】
＜インク組成物（ＩＪ−３）の作製＞
上記顔料樹脂粒子分散液を、粘度は１３ｃｐ、表面張力は２３ｍＮ／ｍに調製してインク組成物（ＩＪ−３）を得た。インク組成物（ＩＪ−３）を、実施例１と同様にしてカラーファクシミリ彩遊記ＵＸ−Ｅ１ＣＬ（シャープ社製）で印刷した所、滲みのない良質の明瞭な印刷を与えた。また実施例１と同様にして耐擦過性を調べた所、目視で地汚れが全くなく極めて耐擦過性に優れていることが判った。インク組成物は、長期に保存しても沈降凝集が見られず分散性が良好であつた。
【０１２８】
比較例１
＜比較用顔料分散液の調製＞
青色顔料としてアルカリブルー　５重量部、顔料分散剤としてラウリルメタクリレート／アクリル酸共重合体（組成比９５／５ｗｔ／ｗｔ）５重量部とを、アイソパーＨ９０重量部及びガラスビーズ２５０重量部とともにペイントシェイカー（東洋精機ＫＫ）で３０分間混合した。次にガラスビーズをろ別した後、高速度分散混和機器ダイノミル（商品名；ＫＤＬ）で回転数３０００ｒｐｍで３時間分散し分散液中の顔料粒子の体積平均粒径を、超遠心式自動粒度分布測定装置ＣＡＰＡ７００（堀場製作所）にて測定した所、０．１３μｍと良好に分散されていた。
【０１２９】
＜比較用着色樹脂粒子の調製＞
ガラスビーズをろ過した顔料分散液のろ液（固形分９．６％）２０８．３ｇを四つ口フラスコに入れ窒素気流下攪拌しながら溶液温度を８０℃で３時間加熱した。次にこの顔料分散液中に、実施例１と同様に、分散安定化剤（Ｐ−１）を６ｇ、メタクリル酸メチル１２．０ｇ、アクリル酸メチル２８．０ｇ及びアイソパーＨ１２０ｇの混合溶液に２，２′−アゾビス（２，４−ジメチルバレロニトリル）１．０ｇを加えた溶液をフィード溶液として、滴下速度２．５ｍｌ／分で滴下しその後３時間反応させた。滴下開始から約１５分して発熱が始まり、反応液温度は約５℃程上昇したが、フラスコ壁面に粗大粒子が付着しており、反応後にはフラスコの底に多量の沈殿物がみられた。比較例１の着色樹脂粒子は、粗大粒子、沈降物の生成のため、次ぎのインク組成物に供することができなかった。
【０１３０】
比較例２〜３
実施例１において、ロジンエステル樹脂処理された黒色顔料マイクロリスブラックＣ−Ｔ　（チバ・スペシャリティ・ケミカルズ社製）の代わりに、下記のポリマーで処理された青色顔料（Ｃ．Ｉ．Ｐｉｇｍｅｔ　Ｂｌｕｅ　１５：３）を用いた他は実施例１と全く同様に顔料分散を行った。

【０１３１】
分散後にガラスビーズをろ別し得られた比較例２〜３の顔料分散液は、体積平均粒径が比較例２で１．４８μｍ、比較例３で１．６７μｍであった。比較例２〜３の顔料分散液は、粗大粒子があり経時で沈降物が生成するなど分散性は良好でないため、次ぎのシード重合に供することができなかった。
【０１３２】
実施例１〜３と比較例１〜３より、本発明の如くポリマー処理された顔料は、特異的に微細粒子化され良好な分散安定性を有し、また、分散安定化剤として重合性二重結合基を有する共重合体を用いたために、シード分散重合が良好に進行し、そのシード分散重合により生成したポリマー処理された顔料を内部に含有する着色樹脂粒子は、明瞭な印刷画質、極めて優れた耐擦過性、良好な長期分散性等の、良好なインク特性を示すことが判った。
【０１３３】
実施例４
＜顔料分散液の調製＞
黒色顔料としてカーボンブラック＃３０（三菱化学社製）１００重量部、ポリマー処理の樹脂としてメチルメタクリレート／ステアリルメタクリレート共重合体（９／１モル比）、２００重量部をトリオブレンダーで予備粉砕しよく混合した後に、１２０℃に加熱した三本ロールミルで溶融混練（２０分）した。上記の顔料混練物をピンミルで粉砕した。
次に顔料混練物１０重量部、アイソパーＧ６５重量部、顔料分散剤としてソルプレン１２０５（旭化成社製、スチレン／ブタジエン共重合体）をアイソパーＧに加熱溶解して調液した２０ｗｔ％溶液を２５重量部、及び３Ｇ−Ｘガラスビーズ２５０重量部とともにペイントシェイカー（東洋精機ＫＫ）で６０分間混合した。次にガラスビーズをろ別した後、高速度分散混和機器ダイノミル（商品名；ＫＤＬ）で回転数３０００ｒｐｍで３時間分散した。メディアはガラスビーズＭＫ−３ＧＸを使用した。分散液中の顔料粒子の体積平均粒径を、超遠心式自動粒度分布測定装置ＣＡＰＡ７００（堀場製作所）にて測定した所、０．２１μｍと良好に分散されていた。
【０１３４】
＜着色樹脂粒子の調製＞
ガラスビーズをろ過した顔料分散液のろ液（固形分１４．０％）２１４．３ｇを四つ口フラスコに入れ窒素気流下攪拌しながら温度５０℃で１時間加熱した。次にこの顔料分散液中に、上記の分散安定化剤（Ｐ−２）を粉体で４ｇ、アクリル酸メチル２０．０ｇ及びアイソパーＨ８０ｇの混合溶液に２，２′−アゾビス（４−メトキシ−２，４−ジメチルバレロニトリル）０．７ｇを加えた溶液をフィード溶液として、一時間で滴下しその後３時間反応させた。滴下開始から約２０分して発熱が始まり、反応液温度は約５℃程上昇した。３時間反応後に温度を５０℃から８０℃に上げ窒素流量を上げながら、２時間攪拌し未反応のモノマーを留去した。冷却後２００メッシュのナイロン布を通し得られた黒色樹脂粒子分散液は重合率９２％でその体積平均粒子サイズは０．２４μｍであった。得られた黒色樹脂粒子分散液は、１カ月静置保存した後の分散状態も良好であった。
【０１３５】
＜インク組成物（ＩＪ−４）の作製＞
上記着色樹脂粒子分散液を、溶媒留去により一旦濃縮しアイソパーＧにて希釈する事により、粘度は１３ｃｐ、表面張力は２３ｍＮ／ｍのインク組成物ＩＪ−４を調製した。インク組成物ＩＪ−４を、実施例１と同様にしてカラーファクシミリ彩遊記ＵＸ−Ｅ１ＣＬ（シャープ社製）で印刷した所、滲みのない良質の明瞭な印刷を与えた。また実施例１と同様にして耐擦過性を調べた所、目視で地汚れが全くなく極めて耐擦過性に優れていることが判った。インク組成物は、長期に保存しても沈降凝集が見られず分散性が良好であつた。
【０１３６】
比較例４
＜比較用インク組成物（ＩＪＲ−１）の作製＞
実施例４の着色樹脂粒子の代わりにシード粒子の顔料分散液を用いた他は、インク組成物（ＩＪ−４）と同様にして、比較用インク組成物（ＩＪＲ−１）を作成した。インクの粘度は１２ｃｐ、表面張力は２３ｄｙｎｅ／ｃｍであった。比較用インク組成物（ＩＪＲ−１）を、実施例１と同様にしてカラーファクシミリ彩遊記ＵＸ−Ｅ１ＣＬ（シャープ社製）で印刷した所、滲みのない印刷を与えたものの、ベタ画像部を指で擦ると簡単に画像部が取れてしまい、耐擦過性が極めて悪い事が判った。更に、得られた印刷画像部を指で擦って取れないようにするには、印刷記録体を１２０℃以上に加熱定着する必要がある事が判った。
【０１３７】
本発明のインク組成物（ＩＪ−４）と比較用インク組成物（ＩＪＲ−１）の実験結果より、本発明の如くポリマー処理された顔料をシード粒子として、重合性二重結合基を有する分散安定化剤を用いたシード分散重合により、低軟化性の樹脂で被覆された着色樹脂粒子は、明瞭な印刷画質、良好な易定着性、極めて優れた耐擦過性、良好な長期分散性等の、良好なインク特性を示すことが判った。
【０１３８】
実施例５
＜顔料分散物の調製＞
実施例１において、黒色顔料マイクロリスブルーＣ−Ｔ　（チバ・スペシャリティ・ケミカルズ社製）の代わりに、黄色顔料マイクロリスイェロ−３Ｒ−Ｔ　（チバ・スペシャリティ・ケミカルズ社製）を用いた他は実施例１と全く同様に顔料分散を行った。ガラスビーズをろ別した後得られた黄色顔料の分散液は、体積平均粒径が０．２０μｍと分散性は良好であった。
【０１３９】
＜着色樹脂粒子の調製＞
黄色顔料の分散液（固形分２０．０％）１００ｇを四つ口フラスコに入れ窒素気流下攪拌しながら温度８０℃で２時間加熱した。実施例１において、分散安定化剤として（Ｐ−６）を粉体で４ｇ、メタクリル酸メチル６．０ｇ、アクリル酸メチル１２．０ｇ、ジメチルアミノエチルメタクリレート２．０ｇ及びアイソパーＨ８０ｇの混合溶液に２，２′−アゾビス（２，４−ジメチルバレロニトリル）０．６ｇを加えた溶液をフィード溶液として、滴下速度２．０ｍｌ／分で滴下し３時間反応させた他は、実施例１と全く同一の反応操作を行った。反応液温度は約４℃程上昇した。得られた黄色樹脂分散液は、重合率９５％、体積平均粒子サイズは０．２６μｍであり、１カ月静置保存した後の分散状態も良好であった。
【０１４０】
＜インク組成物（ＩＪ−５）の作製＞
黄色樹脂粒子分散液をアイソパーＧで樹脂粒子成分が６．０％になる様希釈した。次いで荷電調節剤としてオクタデセン−半マレイン酸オクタデシルアミド共重合体を、０．０１ｇ／アイソパーＧ　１リットルになる様添加してインク組成物（ＩＪ−５）を調液した。インク組成物（ＩＪ−５）の荷電量の測定を、特公昭６４−６９６号に記載の現像特性装置（印加電圧５００Ｖ、印加した電極の背面に誘起された電圧の時間変化の初期値を測定）で行った。インク組成物（ＩＪ−５）は全体荷電が２４０ｍＶ、黄色樹脂粒子の荷電が２０１ｍＶと明瞭な正荷電性を示し、一ヵ月後の荷電量の変化も殆ど無く極めて安定している事が判った。また、その荷電量は荷電調節剤の量により容易に制御できる事が判った。
【０１４１】
比較例５
＜比較用インク組成物（ＩＪＲ−２）の作製＞
実施例５において、シード粒子である黄色顔料分散物をインク組成物（ＩＪ−５）と同様にインク化して比較用インク組成物（ＩＪＲ−２）を作成した。比較用インク組成物（ＩＪＲ−２）の荷電量を測定したところ、荷電極性は負荷電で、全体荷電が９０ｍＶ、黄色顔料粒子の荷電が１３ｍＶであった。
実施例５と比較例５より、シード粒子の黄色顔料マイクロリスイェロ−３Ｒ−Ｔ（比較用インク組成物（ＩＪＲ−２））の荷電極性はもともと負荷電であるが、側鎖に二重結合基を含有する共重合体を分散安定化剤としたシード分散重合により樹脂被覆した本発明の着色樹脂粒子（インク組成物（ＩＪ−５））は、荷電極性が明瞭な正荷電を示し、その荷電量も荷電調節剤の量により容易に制御できる事が判る。即ち、もともとの顔料の荷電極性に依らず、シード分散重合により顔料表面を樹脂被覆する事により、荷電極性（適切に荷電調節剤を選択して）、荷電量を自由に制御できることが判る。
【０１４２】
＜画像描画性＞
インクジェツト装置として、図−１に示すヘッド構造の１００ｄｐｉ　６４チャンネルの静電式インクジェツトヘッドを使用し、インク組成物（ＩＪ−５）をインクタンクに充填した。エアーポンプ吸引により記録媒体であるコート記録紙表面の埃除去を行った後、吐出ヘッドを描画位置までコート記録紙に近づけ、描画解像度６００ｄｐｉでインクを吐出し描画した。この際、パルス電圧を調節してドット径１５μｍから６０μｍの範囲で１６段階でドット面積を変化させながら描画した。描画画像は滲みのない満足し得る濃度の良質の明瞭な画像を与えた。インクヘッドからの吐出安定性も良好で、詰まりを生じる事が無く、画像描画でも安定したドット形状の印字ができた。また実施例１と同様にして耐擦過性を調べた所、目視で地汚れが全くなく極めて耐擦過性に優れていた。インク組成物（ＩＪ−５）は、長期に保存しても沈降凝集が見られず分散性が良好であった。
【０１４３】
一方、比較用インク組成物（ＩＪＲ−２）を用い、吐出ヘッドに印加するパルス電圧を負極性にして上記と同様に描画した所、描画画像は滲みがひどく画像濃度も低いものであった。また、吐出不良が発生したために、画像欠落が見られ満足する画像が得られなかった。
以上の結果より、本発明のシード分散重合により樹脂被覆した顔料樹脂粒子（インク組成物（ＩＪ−５））が、明瞭な正荷電と十分な荷電量も有するために、静電式インクジェツト装置において、明瞭な印刷画質、良好な吐出安定性、極めて優れた耐擦過性、良好な長期分散性等の、良好なインク特性を示すことが判った。
【０１４４】
実施例６〜１９
＜顔料分散液の調製＞
実施例１において、顔料分散剤（Ｄ−１）の代わりに（Ｄ−３）を加工顔料に対して５０ｗｔ％用い、また黒色加工顔料マイクロリスブラックＣ−Ｔの代わりに、青色加工顔料マイクロリスブルー４Ｇ−Ｔ（チバ・スペシャリティ・ケミカルズ社製）を用いた他は実施例１と全く同様に顔料分散を行った。ガラスビーズをろ別した後得られた顔料分散液は、体積平均粒径は０．１６μｍで分散性は良好であった。この黒色顔料分散液を用いてシード分散重合を行い着色樹脂粒子、インク組成物（ＩＪ−６）〜（ＩＪ−１９）をそれぞれ作成した。
【０１４５】
＜着色樹脂粒子＞
実施例１において、青色加工顔料分散液（固形分１９．１％）１５７．５ｇを用い、下記の表−Ｂに記載の分散安定化剤（Ｐ）を粉体で８ｇ、単量体を４０ｇ、アイソパーＧを１２０ｇ、２，２′−アゾビス（２，４−ジメチルバレロニトリル）を単量体の１モル％加えた溶液をフィード溶液と２時間で滴下して他は、実施例１と全く同一の反応操作を行った。反応液温度はそれぞれ約３〜８℃程上昇した。得られた青色粒子分散液６〜１９は、重合率が約８９〜９８％であり、その体積平均粒子サイズは０．２０〜０．２６μｍであった。また青色粒子分散液６〜１９は、１カ月静置保存した後の分散状態もそれぞれ良好であった。
【０１４６】
＜インク組成物：ＩＪ−６〜ＩＪ−１９＞
上記着色樹脂粒子分散液６〜１９を、それぞれ粘度は１２〜１４ｃｐ、表面張力は２２〜２４ｍＮ／ｍに調整してインク組成物（ＩＪ−６）〜（ＩＪ−１９）を得た。インク組成物（ＩＪ−６）〜（ＩＪ−１９）を、実施例１と同様にしてカラーファクシミリ彩遊記ＵＸ−Ｅ１ＣＬ（シャープ社製）で印刷した所、インク組成物（ＩＪ−６）〜（ＩＪ−１９）は、滲みのない満足し得る濃度の良質の明瞭な印刷を与え、また目視で地汚れが全くなく極めて耐擦過性に優れていた。また、インク組成物（ＩＪ−６）〜（ＩＪ−１９）は、長期に保存しても沈降凝集が見られず分散性が良好であつた。
【０１４７】
【表２】

【０１４８】
実施例２０
実施例５で得られたインク組成物（ＩＪ−５）を電子写真用液体現像剤として、リコー製湿式複写機ＤＴ−２５００を用いて印字テストしたところ、十分な画像濃度と良好な定着性を有する画像が得られた。また、この電子写真用液体現像剤は荷電の経時変化が極めて少なく、再分散性、保存安定性に優れるものであった。
【０１４９】
【発明の効果】
表面処理された着色剤をシード粒子として、非水溶媒中で側鎖に二重結合基を含有する共重合体を分散安定化剤としたシード分散重合により得られる、樹脂で被覆された本発明の着色樹脂粒子を含有するインク組成物により、着色剤が均一に微粒子分散され、且つ着色剤分散液の分散安定性に優れるインクジェットプリンタ用油性インクを得ることができる。また、ノズル部での目詰まりが起きない吐出安定性の高いインクジェットプリンタ用油性インクが得られる。更に記録紙上での乾燥性、記録画像の耐水性、耐光性に優れており、且つ高度の耐擦過性を有するインクジェットプリンタ用油性インクが得られる。また、分散安定性、耐擦過性に優れると共に、荷電極性の制御や荷電の経時安定性にも優れた静電方式インクジェツトプリンタ用油性インク、及び電子写真用液体現像剤を得ることができる。更に上記の特徴を有する、均一に微粒子分散された着色剤を内包する樹脂粒子の製造方法を提供できる。
【０１５０】
【図面の簡単な説明】
【図１】ライン走査型マルチチャンネルインクジェツトヘッドの構成例を示し、記録ドットに対応した吐出電極の断面を示す図である。
【図２】吐出電極を記録媒体側から見た図である。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an oil-based ink for use in an ink jet recording apparatus for flying ink and forming characters and images on a transfer medium such as recording paper, and in particular, colored component particles in which colored resin particles are surface-treated with a colorant. Further, the present invention relates to an oil-based ink which is a colored resin particle coated with a polymer, an electrophotographic developer, and a method for producing the colored resin particle.
[0002]
[Prior art]
Conventionally, as an ink jet recording method, an on-demand (optional jet) and a continuous (continuous jet) method are known, an electrostatic method (Sweet type, Hertz type) in a continuous type, a piezoelectric method in an on-demand type, A recording method called a share mode piezoelectric method, a thermal ink jet method, an electrostatic acceleration type, and the like are known.
The ink used in these ink jet recording methods is generally water-based ink because it is free from ink clogging in the ink discharge section and ink supply path, has excellent discharge stability, and has good color image quality such as color and gloss. Is used.
[0003]
As an on-demand ink jet method using electrostatic force, a method called electrostatic acceleration ink jet or slit jet is known. This is because ink is supplied from an ink tank to a slit-shaped ink chamber in which a large number of electrodes are arranged on the inner surface of the slit-shaped ink holding portion, and a high voltage is selectively applied to these electrodes, thereby being close to the slit. Recording is performed by ejecting ink in the vicinity of the electrodes onto the opposing recording paper.
[0004]
On the other hand, a concentrated discharge type electrostatic system that does not use a slit-like recording head is also known. This is a control comprising a plurality of individual electrodes for applying an electrostatic force to a colorant component in ink, and an insulating substrate having a through hole and a control electrode formed corresponding to the through hole. It consists of an electrode substrate and a convex ink guide arranged almost at the center of this through hole. The surface of this convex ink guide is transported to the ink droplet flying position by surface tension, and a predetermined voltage is applied to the control electrode. Is applied to cause ink droplets to fly on the recording medium for recording.
[0005]
As inks used in such various ink jet recording systems, various water-soluble dyes are dissolved in water or a solvent composed of water and a water-soluble organic solvent, and various additives are added as necessary. (Hereinafter referred to as water-based dye ink). However, when actual printing is performed using water-based dye ink, the ink bleeds on the recording paper depending on the paper type, and high-quality printing cannot be obtained, and the formed recorded image has poor water resistance and light resistance. There are drawbacks such as deterioration of the recorded image due to color mixing (color turbidity or color unevenness occurring at the color boundary surface when different color dots are printed adjacent to each other), which is slow to dry on paper and causes tailing.
[0006]
Therefore, in order to improve the water resistance and light resistance of the recorded image, which is a problem of the aqueous dye ink described above, an ink jet recording method is used for pigment-based inks in which pigment fine particles are dispersed in an aqueous solvent or a non-aqueous solvent body. Various attempts have been made to apply the ink to an ink jet printer, for example, an ink for an ink jet printer in which a pigment is dispersed in a solvent containing water as a main component. However, since the pigment is insoluble in the medium, it generally has problems such as poor dispersion stability and easy clogging at the nozzle portion.
[0007]
On the other hand, an ink in which a pigment is dispersed in a nonpolar insulating solvent (hereinafter referred to as an oil-based pigment ink) has advantages such as less bleeding due to its good absorbability to paper, and good water resistance of recorded images. For example, in Patent Document 1 (Japanese Patent Laid-Open No. 57-10660), the pigment is finely divided by an alcohol amide-based dispersant, and in Patent Document 2 (Japanese Patent Laid-Open No. 57-10661), a sorbitan-based dispersant. Oil-based pigment inks have been proposed. However, the pigment particles are not sufficient to uniformly disperse the fine particles in the nonpolar insulating solvent, and the dispersion stability is poor, so that there are still problems such as the nozzle portion being easily clogged. Furthermore, since the pigment itself does not have a fixing ability with respect to the recording paper, it has a great drawback that it has poor scratch resistance.
[0008]
In order to improve these, a resin-soluble oil-based ink that uses a resin soluble in a nonpolar insulating solvent as both a fixing agent and a pigment dispersant has been proposed. No. 234772) proposes a terpene phenol resin as the above resin. However, the dispersion stability of the pigment is not yet sufficient, and there is a problem in the reliability as an ink. Further, since the resin is dissolved in a non-polar solvent, there is no resin left to completely fix the pigment on the recording paper, and the water resistance and scratch resistance are not sufficient.
[0009]
Accordingly, in order to obtain a higher degree of scratch resistance, it has been proposed to coat pigment particles with a resin that is insoluble or semi-dissolved in a nonpolar insulating solvent. For example, Patent Document 4 (Japanese Patent Laid-Open No. 4-25574) is proposed. (Patent Publication) proposes an oil-based ink in which a pigment is coated with a resin by a microcapsule method or the like. However, since it is difficult to uniformly disperse the pigment-encapsulating resin particles and the dispersion stability thereof is not sufficient, there is a problem in reliability as an ink.
[0010]
Furthermore, in recent years, high-quality photographic quality has been achieved with general inkjet printers that use water-based dye inks, and pigments are made as fine as possible and dispersed in pigment inks in order to improve color development and transparency. There has been a demand to keep the state stable.
However, on the other hand, as the pigment becomes finer, the primary particles of the pigment are crushed simultaneously with the miniaturization of the pigment, and further, the aggregation energy increases simultaneously with the increase of the surface energy, so reaggregation easily occurs. Eventually, there is a problem that the storage stability of the finely divided pigment dispersion is impaired. As described above, the demand for pigment dispersions used in oil-based pigment inks for ink jet printers requires a higher degree of fineness. It is very difficult to improve the properties, and there are few oil pigment inks that satisfy the above.
[0011]
Furthermore, when these oil-based pigment inks are used in electrostatic inkjet printers and electrophotographic liquid developers, the charge polarity and charge stability over time are required, but the pigment surface polarity is controlled. Since it is very difficult to do so, it is a fact that there is no oil-based pigment ink that satisfies the above. The electrophotographic liquid developer using a non-aqueous solvent generally comprises an aliphatic hydrocarbon solvent, a colorant, a fixing resin, a dispersant, and various additives added as necessary. The mixture is manufactured by pulverizing with a ball mill or an attritor. About the manufacturing method, various proposals have been made so far. For example, a colored liquid developer has been proposed in which a polymer latex obtained by polymerizing styrene or an acrylic monomer in a non-aqueous solvent is dyed with a dye, and this is used as a colorant. However, the method using a dye as a colorant has the disadvantages that it is difficult to produce a black liquid developer, and that the dye system is low in image density and photobleaching. On the other hand, as an example of using a pigment as a colorant, a resin obtained by reacting a pigment as a liquid developer for electrophotography and a natural resin-modified thermosetting resin as a fixing resin in a long chain alkyl group-containing monomer is proposed. Yes. However, although it is effective in improving the dispersion stability of the colorant, it has not yet had sufficient dispersion stability. Thus, a liquid developer for electrophotography using a pigment as a colorant has been desired to have sufficient dispersion stability as well as scratch resistance. Furthermore, since the charge polarity of the pigment differs depending on the type, it has been desired that the charge polarity of the pigment particles is clarified and that the charge does not change with time.
[0012]
[Patent Document 1]
Japanese Patent Laid-Open No. 57-10660
[Patent Document 2]
Japanese Patent Laid-Open No. 57-10661
[Patent Document 3]
JP-A-3-234472
[Patent Document 4]
JP-A-4-25574
[0013]
[Problems to be solved by the invention]
Accordingly, a first object of the present invention is to provide an oil-based ink jet printer with high ejection stability that does not cause clogging in the nozzle portion because the pigment is uniformly dispersed in fine particles and the dispersion stability of the pigment dispersion is excellent. To provide ink.
A second object of the present invention is to provide an oil-based ink for an ink jet printer which is excellent in drying properties on recording paper, water resistance and light resistance of recorded images, and has a high degree of scratch resistance.
The third object of the present invention is to provide an oil-based ink for an electrostatic ink jet printer, which is excellent in dispersion stability and scratch resistance, as well as charge polarity control and charge aging stability, and electrophotographic liquid development. It is to provide an agent.
A fourth object of the present invention is to provide a production method for obtaining an ink for an ink jet printer having the above-described characteristics and comprising resin particles enclosing a pigment dispersed uniformly in fine particles.
[0014]
[Means for Solving the Problems]
It has been found that the above problem can be solved by the following configuration.
(1) In a non-aqueous solvent having a dielectric constant of 1.5 to 20 and a surface tension of 15 to 60 mN / m (at 25 ° C.), a coloring component obtained by surface-treating a colorant is dispersed in the form of fine particles in the non-aqueous solvent. Using the colored component fine particles obtained as a seed particle, at least one monofunctional monomer (M) and a polymerizable double bond at the terminal of the substituent of the polymer repeating component that is soluble in the non-aqueous solvent An ink jet comprising colored resin particles obtained by adding at least one dispersion stabilizer (P) having a group-containing polymer as a main component and dispersing and polymerizing in the presence of a polymerization initiator Oil-based ink composition for printers.
[0015]
(2) The dispersion stabilizer (P) is soluble in the nonaqueous solvent and is soluble in the nonaqueous solvent represented by the following general formula (I), and the following general formula (II): The dispersion stabilizer (P) having as a main component a polymer component B having a polymerizable double bond group at the terminal of the substituent of the polymer repeating component shown in the above (1) Oil-based ink composition for inkjet printers.
[0016]
[Chemical 3]

[0017]
In general formula (I), X ⁰ Is —COO—, —OCO—, — (CH ₂ ) _k -OCO-,-(CH ₂ ) _k It represents one or a combination of linking groups selected from —COO— and —O—. k represents an integer of 1 to 3.
a ¹ And a ² May be the same or different from each other, and each represents a hydrogen atom, a halogen atom, a cyano group, a hydrocarbon group, —COO—Z. ¹ Or -COO-Z via hydrocarbon ¹ (Z ¹ Represents a hydrogen atom or an optionally substituted hydrocarbon group.
Q ⁰ Represents an aliphatic group having 4 to 22 carbon atoms.
[0018]
[Formula 4]

[0019]
In general formula (II), X ¹ And X ³ May be the same as or different from each other, and each represents —COO—, —OCO—, — (CH ₂ ) _k COO-,-(CH ₂ ) _k OCO-, -O-, -SO ₂ -, -CONHCOO-, -CONHCONH-, -CON (Z ² )-Or -SO ₂ N (Z ² )-. Where Z ² Represents a hydrogen atom or a hydrocarbon group having 1 to 22 carbon atoms, and k represents an integer of 1 to 4.
W is a linking group X ¹ And linking group X ² And a group consisting of at least one carbon atom, oxygen atom, sulfur atom, silicon atom or nitrogen atom.
b ¹ And b ² , C ¹ And c ² Is a in the general formula (I) ¹ And a ² It is synonymous with.
[0020]
(3) The inkjet printer according to the above (1), wherein the colorant is at least one pigment selected from organic pigments and inorganic pigments, and the color component is surface-treated by coating the colorant with a polymer. Oil-based ink composition.
(4) The oil-based ink composition for inkjet printers according to (1), wherein the seed particles are colored component fine particles obtained by dispersing and stabilizing the surface-treated colored component in a fine particle form in a non-aqueous solvent using a pigment dispersant. .
[0021]
(5) Volume resistivity 10 ⁹ At least a monofunctional monomer (M) is obtained using, as seed particles, colored component fine particles obtained by dispersing a colored component obtained by surface-treating a colorant in a non-aqueous solvent of Ωcm or more into fine particles in the non-aqueous solvent. One kind and at least one dispersion stabilizer (P) which is soluble in the non-aqueous solvent and has as a main component a polymer having a polymerizable double bond group at the terminal of the substituent of the polymer repeating component. In addition, a liquid developer for electrophotography characterized by containing colored resin particles obtained by dispersion polymerization in the presence of a polymerization initiator.
(6) The dispersion stabilizer (P) is a polymer component A that is soluble in the non-aqueous solvent represented by the above general formula (I) and a polymer repeating component represented by the above general formula (II). The liquid developer for electrophotography as described in (5) above, which is a dispersion stabilizer mainly comprising a polymer component B having a polymerizable double bond group at the end of the group.
[0022]
(7) The electrophotography according to the above (5), wherein the colorant is at least one pigment selected from organic pigments and inorganic pigments, and the coloring component is surface-treated by coating the colorant with a polymer. Liquid developer.
(8) The electrophotographic liquid developer according to the above (5), wherein the seed particles are colored component fine particles obtained by dispersing and stabilizing the surface-treated colored component in the form of fine particles in a non-aqueous solvent using a pigment dispersant.
[0023]
(9) In a non-aqueous solvent having a dielectric constant of 1.5 to 20 and a surface tension of 15 to 60 mN / m (at 25 ° C.), a coloring component whose surface is treated with a colorant is dispersed in the form of fine particles in the non-aqueous solvent. Using the coloring component fine particles obtained as seed particles, at least one of the monofunctional monomer (M) and a polymerizable double bond at the terminal of the substituent of the polymer repeating component that is soluble in the non-aqueous solvent A method for producing colored resin particles, characterized in that a dispersion obtained by adding at least one dispersion stabilizer (P) mainly composed of a polymer having a group is dispersed in the presence of a polymerization initiator.
(10) The dispersion stabilizer (P) is a polymer component A that is soluble in the non-aqueous solvent represented by the above general formula (I) and a polymer repeating component represented by the above general formula (II) The method for producing colored resin particles according to (9) above, which is a dispersion stabilizer mainly comprising a polymer component B having a polymerizable double bond group at the terminal of the group.
[0024]
(11) The method for producing colored resin particles according to (9), wherein the colorant is at least one pigment selected from organic pigments and inorganic pigments, and the colorant is polymer-coated and surface-treated. .
(12) The colored resin particles according to (9) above, wherein the colored component fine particles are obtained by dispersing and stabilizing the surface-treated colored components in the form of fine particles in the non-aqueous solvent using a pigment dispersant. Method.
[0025]
DETAILED DESCRIPTION OF THE INVENTION
The present invention is described in detail below.
The non-aqueous solvent used in the oil-based ink composition for inkjet printers of the present invention is a non-polar insulating solvent having a dielectric constant of 1.5 to 20 and a surface tension of 15 to 60 mN / m (at 25 ° C.). Preferably there is. Further, the non-aqueous solvent used for the electrophotographic liquid developer has a volume resistivity of 10 ⁹ It is preferable that it is Ωcm or more. Further desirable properties are low toxicity, low flammability, and low odor.
[0026]
Examples of such a non-aqueous solvent include a solvent selected from linear or branched aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons, petroleum naphtha, and halogen-substituted products thereof. For example, hexane, octane, isooctane, decane, isodecane, decalin, nonane, dodecane, isododecane, Isopar E from Exxon, Isopar G, Isopar H, Isopar L, Saltol from Philippe Petroleum, IP Solvent from Idemitsu Petrochemical, Petroleum Naphtha Then, Shell Petrochemical's S. B. R. , Shellzol 70, Cielzol 71, Mobil Petroleum's begazole, and the like can be used alone or in combination.
[0027]
Preferable hydrocarbon solvents include high-purity isoparaffinic hydrocarbons having a boiling point in the range of 150 to 350 ° C., and commercially available products such as Isopar G, H, L, M, and V (manufactured by Exxon Chemical Co., Ltd.) Name), Noper 12, 13, 15 (trade name), IP Solvent 1620, 2028 (trade name) manufactured by Idemitsu Petrochemical, Isosol 300,400 (trade name) manufactured by Nippon Petrochemical, Amsco OMS, Amsco 460 solvent ( Amsco; a brand name of Spirits). These products are highly saturated aliphatic saturated hydrocarbons, the viscosity at 25 ° C. is 3 cSt or less, the surface tension at 25 ° C. is 22.5 to 28.0 mN / m, and the specific resistance at 25 ° C. is 10 ¹⁰ Ω · cm or more. In addition, it is characterized by low reactivity and stability, low toxicity, high safety, and low odor.
[0028]
Examples of halogen-substituted hydrocarbon solvents include fluorocarbon solvents such as C ₇ F ₁₆ , C ₈ F ₁₈ C such as _n F _{2n + 2} Perfluoroalkanes represented by (Sumitomo 3M "Fluorinert PF5080", "Florinato PF5070" (trade name), etc.), fluorine-based inert liquid (Sumitomo 3M "Fluorinert FC series" (trade name), etc. ), Fluorocarbons ("Crytox GPL series" (trade name) manufactured by DuPont Japan Limited), chlorofluorocarbons ("HCFC-141b" (trade name) manufactured by Daikin Industries, Ltd.), [F (CF ₂ ) ₄ CH ₂ CH ₂ I], [F (CF ₂ ) ₆ I] and the like (“I-1420”, “I-1600” (trade name), etc., manufactured by Daikin Fine Chemical Laboratory) and the like.
[0029]
As the non-aqueous solvent used in the present invention, higher fatty acid esters and silicone oils can also be used. Specific examples of silicone oil include low-viscosity synthetic dimethylpolysiloxane, and commercially available products include KF96L (trade name) manufactured by Shin-Etsu Silicone, SH200 (trade name) manufactured by Toray Dow Corning Silicone, and the like. It is done.
The silicone oil is not limited to these specific examples. These dimethylpolysiloxanes are available in a very wide viscosity range depending on the molecular weight, but it is preferable to use those in the range of 1 to 20 cSt. These dimethylpolysiloxanes, like isoparaffinic hydrocarbons, are 10 ¹⁰ It has a volume resistivity of Ω · cm or more, and has characteristics such as high stability, high safety, and odorlessness. These dimethylpolysiloxanes are characterized by low surface tension and have a surface tension of 18 to 21 mN / m.
[0030]
Solvents that can be used in combination with these organic solvents include alcohols (eg, methyl alcohol, ethyl alcohol, propyl alcohol, butyl alcohol, fluorinated alcohol), ketones (eg, acetone, methyl ethyl ketone, cyclohexanone, etc.), carvone Acid esters (eg, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, methyl propionate, ethyl propionate, etc.), ethers (eg, diethyl ether, dipropyl ether, tetrahydrofuran, dioxane, etc.) and halogenated hydrocarbons ( Examples thereof include solvents such as methylene dichloride, chloroform, carbon tetrachloride, dichloroethane, methyl chloroform, and the like.
[0031]
Next, the surface-treated coloring component of the present invention will be described in detail.
The surface-treated coloring component of the present invention (hereinafter sometimes simply referred to as “coloring component”) is a surface-treated colorant, and the colorant is not particularly limited and is generally commercially available. All organic and inorganic pigments mentioned are mentioned.
[0032]
For example, C.I. I. Pigment Yellow 1 (Fast Yellow G etc.), C.I. I. A monoazo pigment such as C.I. Pigment Yellow 74; I. Pigment Yellow 12 (disaji yellow AAA, etc.), C.I. I. Disazo pigments such as CI Pigment Yellow 17; I. Non-benzidine azo pigments such as CI Pigment Yellow 180; I. An azo lake pigment such as C.I. Pigment Yellow 100 (eg Tartrazine Yellow Lake); I. Condensed azo pigments such as CI Pigment Yellow 95 (Condensed Azo Yellow GR, etc.); I. Acidic dye lake pigments such as C.I. Pigment Yellow 115 (such as quinoline yellow lake); I. Basic dye lake pigments such as CI Pigment Yellow 18 (Thioflavin Lake, etc.), anthraquinone pigments such as Flavantron Yellow (Y-24), isoindolinone pigments such as Isoindolinone Yellow 3RLT (Y-110), and quinophthalone yellow Quinophthalone pigments such as (Y-138), isoindoline pigments such as isoindoline yellow (Y-139), C.I. I. Nitroso pigments such as CI Pigment Yellow 153 (nickel nitroso yellow, etc.); I. And metal complex salt azomethine pigments such as CI Pigment Yellow 117 (copper azomethine yellow, etc.).
[0033]
As a magenta color, C.I. I. Monoazo pigments such as CI Pigment Red 3 (Toluidine Red, etc.); I. Disazo pigments such as C.I. Pigment Red 38 (Pyrazolone Red B, etc.); I. Pigment Red 53: 1 (Lake Red C, etc.) and C.I. I. Azo lake pigments such as CI Pigment Red 57: 1 (Brilliant Carmine 6B); I. Condensed azo pigments such as CI Pigment Red 144 (condensed azo red BR, etc.); I. Acidic dye lake pigments such as C.I. Pigment Red 174 (Phloxine B Lake, etc.); I. Basic dye lake pigments such as C.I. Pigment Red 81 (Rhodamine 6G ′ lake, etc.); I. Anthraquinone pigments such as C.I. Pigment Red 177 (eg, dianthraquinonyl red); I. Thioindigo pigments such as C.I. Pigment Red 88 (Thioindigo Bordeaux, etc.); I. Perinone pigments such as C.I. Pigment Red 194 (perinone red, etc.); I. Perylene pigments such as C.I. Pigment Red 149 (perylene scarlet, etc.); I. Quinacridone pigments such as C.I. Pigment Red 122 (quinacridone magenta, etc.); I. Isoindolinone pigments such as C.I. Pigment Red 180 (isoindolinone red 2BLT, etc.); I. And alizarin lake pigments such as CI Pigment Red 83 (Mada Lake, etc.).
[0034]
As a pigment exhibiting a cyan color, C.I. Disazo pigments such as CI Pigment Blue 25 (dianisidine blue, etc.); I. Phthalocyanine pigments such as C.I. Pigment Blue 15 (phthalocyanine blue, etc.); I. Acidic dye lake pigments such as C.I. Pigment Blue 24 (Peacock Blue Lake, etc.); I. Basic dye lake pigments such as C.I. Pigment Blue 1 (such as Viclotia Pure Blue BO Lake); I. Anthraquinone pigments such as C.I. Pigment Blue 60 (Indantron Blue, etc.); I. And alkali blue pigments such as CI Pigment Blue 18 (Alkali Blue V-5: 1).
[0035]
Examples of pigments exhibiting a black color include organic pigments such as aniline black pigments such as BK-1 (aniline black), iron oxide pigments, and carbon black pigments such as furnace black, lamp black, acetylene black, and channel black. .
In addition, application of metal powder for color reproduction of gold, silver, copper, etc. is also mentioned.
[0036]
As the surface treatment method of the colorant, methods such as rosin treatment, polymer treatment, grafting treatment, and plasma treatment described in Chapter 5 of “Pigment Dispersion Technology” published by the Technical Information Association can be applied.
[0037]
“Rosin treatment” refers to a method in which pigment and rosin are mechanically kneaded to treat rosin on the surface of the pigment, or after adding an alkaline aqueous solution of rosin to an aqueous slurry of pigment and adding an alkaline earth salt or acid to the rosin. For example, a method of precipitating a slightly soluble salt or a free acid on the pigment particle surface. In the rosin treatment, a rosin of about several to 20% of the pigment is usually used. (1) A fine and highly transparent pigment can be obtained by the effect of preventing the crystal growth of the pigment, and (2) the dry aggregation of the particles is weak. Therefore, mechanical dispersion becomes easy, and (3) it has a great effect in improving the wettability to the oil-based vehicle by increasing the lipophilicity of the pigment surface, and it is often used especially in the field of printing ink. .
[0038]
“Grafting treatment” refers to the grafting reaction between carbon black and inorganic fine particles such as silica and titanium oxide, as well as functional groups such as hydroxyl groups, carboxyl groups and amino groups present on the surface of organic pigments and polymers. Is what you do. In the grafting reaction of the polymer on the pigment surface, (1) the vinyl monomer is polymerized using a polymerization initiator in the presence of the pigment fine particles, and the growth polymer produced in the system is converted into functional groups on the pigment particle surface. A method by stopping, (2) a method of growing a graft chain from a polymerization initiating group introduced to the surface of the pigment fine particle, and (3) a method by a polymer reaction between the functional group on the surface of the pigment fine particle and the functional group at the end of the polymer. There is.
[0039]
“Plasma treatment” is a modification of the pigment powder surface by low-temperature plasma or thermal plasma. Specific examples of the treatment of the pigment surface with low-temperature plasma include (1) modification by plasma irradiation of non-polymerizable gas such as oxygen and nitrogen, (2) modification by plasma-polymerized film formation using polymerizable gas, ( 3) Modification by a plasma-initiated graft polymerization reaction comprising a first stage in which active species are formed on the surface of the substrate by plasma irradiation and a second stage process in which graft polymerization is caused to proceed by subsequent reaction by contacting with the post-irradiation monomer. Quality and so on.
[0040]
As the surface treatment method of the colorant, the polymer treatment described below is particularly preferable from the viewpoint of improving the dispersibility of the colorant and performing dispersion polymerization in a non-aqueous solvent using the dispersed color component as seed particles.
[0041]
As a typical method of polymer treatment, a chemical method using an in-situ polymerization method described in “Pigment Dispersion Technology” on page 99 and later published by the Technical Information Association, a method using a phase separation method (coacervation), The method of processing with a mechanical force at the time of pigment dispersion etc. is mentioned.
[0042]
As an in-situ polymerization method, a pigment and polymer system is dispersed and then suspension polymerization is performed. In the presence of a dispersant, the pigment is dispersed in an aqueous system, and a polar polymer, a vinyl polymer, and a polyfunctional crosslinking polymer are added to perform polymerization. And a method in which the monomer in which the pigment is dispersed is bulk polymerized and then subjected to suspension polymerization or emulsion polymerization so that the pigment can be sufficiently adsorbed. Examples of the phase separation method (coacervation) include a method in which a pigment is dispersed in a polymer solution, and then the solubility of the polymer is lowered by some method to precipitate the polymer from the solution system onto the pigment particles. Compared with the in-situ polymerization method), a wide range of polymers can be selected. Add a non-solvent to the pigment-dispersed resin solution to deposit the resin on the pigment surface, or finely disperse the pigment in the water-soluble polymer or water-soluble resin solution, then adjust the pH to deposit them on the pigment surface This method is widely used including rosin treatment. After dispersing the pigment in an acid solution of acid-soluble nitrogen-containing acrylic resin, increasing the pH to insolubilize the polymer on the pigment surface will prevent aggregation in paints and printing inks, improve fluidity, gloss, and coloring power. The effect is seen. Exemplifying the method of polymer processing by mechanical force, after mixing the polymer and pigment in advance so that the pigment content is 5 to 95%, knead with a kneader, three rolls, etc. while heating and pulverize with a pin mill etc. To do. A method called a flushing resin treatment is also included in the mechanical polymer treatment method.
[0043]
As a resin used for polymer treatment, the dispersibility of the pigment is improved in a non-aqueous solvent, and heat dispersion stability is imparted when the dispersed colored component fine particles are used as seed particles for dispersion polymerization in a non-aqueous solvent. It is preferable that a resin conventionally used in a liquid developer can be used.
[0044]
Preferred resins have a function of adsorbing to a colorant and being well dispersed in a non-aqueous solvent, and therefore have a part that solvates with a solvent, a part that does not easily solvate with a solvent, and a part that has a polar group. Resins are preferred. For example, examples of the monomer that solvates with a solvent after polymerization include lauryl methacrylate, stearyl methacrylate, 2-ethylhexyl methacrylate, and cetyl methacrylate. Examples of monomers that are difficult to solvate with the solvent after polymerization include methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, styrene, and vinyl toluene. Monomers containing polar groups include acrylic acid, methacrylic acid, itaconic acid, fumaric acid, maleic acid, styrene sulfonic acid or alkali salts thereof, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, vinyl pyridine, vinyl Examples include basic group monomers such as pyrrolidine, vinylpiperidine, and vinyllactam.
[0045]
Specific examples of the resin used for polymer treatment include olefin polymers and copolymers (for example, polyethylene, polypropylene, polyisobutylene, ethylene-vinyl acetate copolymer, ethylene-acrylate copolymer, ethylene-methacrylate copolymer, ethylene -Methacrylic acid copolymer, etc.), polymers of styrene and its derivatives and copolymers (eg butadiene-styrene copolymer, isoprene-styrene copolymer, styrene-methacrylate copolymer, styrene-acrylate copolymer, etc.) ), Acrylate polymers and copolymers, methacrylate polymers and copolymers, itaconic acid diester polymers and copolymers, maleic anhydride copolymers, rosin resins, hydrogenated rosin resins, petroleum resins, Hydrogenated petroleum resin, maleic acid tree , Terpene resins, hydrogenated terpene resins, chroman - indene resins, cyclized rubber - methacrylic acid ester copolymers, cyclized rubber - like acrylic acid ester copolymer.
[0046]
The ratio of the colorant of the present invention to the resin used in the polymer treatment is preferably in the range of 95/5 to 5/95, more preferably in the range of 80/20 to 10/90, by weight ratio of the colorant / resin. .
[0047]
In addition, commercially available processed pigments can also be used as the surface-treated coloring component. Specific examples of commercially available processed pigments include microlith pigments manufactured by Ciba Specialty Chemicals, and preferred examples of processed pigments include Microlith-T pigments in which the pigment is coated with a rosin ester resin.
[0048]
In the present invention, the surface-treated colored component is dispersed in the form of fine particles in a non-aqueous solvent to obtain colored component fine particles, which are further dispersed and polymerized as seed particles. First, the coloring component dispersion step will be described.
In the dispersion step, it is preferable to use a pigment dispersant in order to disperse the coloring component in the form of fine particles and to stabilize the dispersion in a non-aqueous solvent.
[0049]
As the pigment dispersant for dispersing the surface-treated colored component in the form of fine particles in a non-aqueous solvent that can be used in the present invention, a general pigment dispersant applied in the non-aqueous solvent can be used. . Any pigment dispersant may be used as long as it is compatible with the nonpolar insulating solvent and can stably disperse the coloring component in fine particles.
[0050]
Specific examples of the pigment dispersant include sorbitan fatty acid esters (sorbitan monooleate, sorbitan monolaurate, sorbitan sesquioleate, sorbitan trioleate, etc.), polyoxyethylene sorbitan fatty acid esters (polyoxyethylene sorbitan monostearate, polyoxyethylene Oxyethylene sorbitan monooleate), polyethylene glycol fatty acid ester (polyoxyethylene monostearate, polyethylene glycol diisostearate, etc.), polyoxyethylene alkyl phenyl ether (polyoxyethylene nonyl phenyl ether, polyoxyethylene octyl phenyl ether) Etc.), nonionic surfactants such as aliphatic diethanolamides, and polymer dispersants having a molecular weight of 1000 or more Good, for example, styrene-maleic acid resin, styrene-acrylic resin, rosin, BYK-160, 162, 164, 182 (urethane polymer compound manufactured by Big Chemie), EFKA-47, LP-4050 (EFKA) For example, urethane dispersants manufactured by the manufacturer, Solspers 24000 (polyester polymer compound manufactured by Zeneca), Solsperse 17000 (aliphatic diethanolamide manufactured by Zeneca), and the like.
[0051]
In addition to the above, the polymeric pigment dispersants include monomers such as lauryl methacrylate, stearyl methacrylate, 2-ethylhexyl methacrylate, and cetyl methacrylate that are solvated in a solvent, and methyl methacrylate, ethyl methacrylate, and isopropyl that are difficult to solvate in a solvent. Examples thereof include random copolymers composed of monomers having a polar group and monomers such as methacrylate, styrene and vinyltoluene, and graft copolymers disclosed in JP-A-3-188469. Examples of the monomer containing the polar group include acidic group monomers such as acrylic acid, methacrylic acid, itaconic acid, fumaric acid, maleic acid, styrene sulfonic acid, and alkali salts thereof, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, and vinylpyridine. And basic group monomers such as vinylpyrrolidine, vinylpiperidine, and vinyllactam. Other examples include styrene-butadiene copolymers and block copolymers of styrene and long-chain alkyl methacrylates disclosed in JP-A-60-10263. Preferable pigment dispersants include graft copolymers disclosed in JP-A-3-188469.
[0052]
The amount of the pigment dispersant used is preferably 0.1 to 300 parts by weight with respect to 100 parts by weight of the colorant. When the amount of the pigment dispersant added is less than 0.1 parts by weight, the dispersion effect of the coloring component is small, which is not preferable. Moreover, even if it uses more than 300 weight part, the effect for the used part is not acquired.
[0053]
In dispersing the surface-treated colorant in the non-aqueous solvent, examples of the method of using the pigment dispersant include the following methods, and any of these methods can provide the intended effect.
[0054]
1. A coloring component composition obtained by previously mixing a surface-treated colorant and a pigment dispersant is added and dispersed in a non-aqueous solvent.
2. A colorant and a pigment dispersant surface-treated in a non-aqueous solvent are separately added and dispersed.
3. A dispersion obtained by separately dispersing a colorant and a pigment dispersant surface-treated in a non-aqueous solvent in advance is mixed. In this case, the pigment dispersant may be dispersed only with a solvent.
4). After dispersing the surface-treated colorant in a non-aqueous solvent, a pigment dispersant is added to the resulting colored component dispersion.
[0055]
The surface-treated colorant (coloring component) can be mixed or dispersed in a non-aqueous solvent to form colored component fine particles. As a machine for mixing or dispersing in a non-aqueous solvent, a dissolver, a high speed mixer, a homomixer, a kneader, a ball mill, a roll mill, a sand mill, an attritor or the like can be used. The range of the dispersion average particle diameter of the coloring component (processed pigment or the like) in this dispersion step is 0.01 to 10 μm. A preferable dispersion average particle diameter range of the coloring component in the ink is 0.01 to 1.0 μm.
[0056]
Next, the step of dispersing and polymerizing the dispersed colored component fine particles as seed particles (seed) by adding a monofunctional monomer (M) to the seed particles will be described.
In a non-aqueous solvent, coloring components are dispersed in the form of fine particles to form seed particles, and a monofunctional monomer (M) has a polymerizable double bond group at the terminal of the substituent of the polymer repeating component. By polymerizing the polymerization system to which the dispersion stabilizer (P) has been added in the presence of the polymerization initiator, colored resin particles encapsulating the colorant of the present invention can be obtained. The monomer (M) may be any monomer as long as it is soluble in the non-aqueous solvent but becomes insoluble in the non-aqueous solvent upon polymerization.
Specifically, for example, a polymerization monomer represented by the following general formula (III) can be mentioned.
[0057]
[Chemical formula 5]

[0058]
In general formula (III), X ² Is —COO—, —OCO—, —CH ₂ OCO-, -CH ₂ COO-, -O-, -CONHCOO-, -CONHOCO-, -SO ₂ -, -CON (Z ² )-, -SO ₂ N (Z ² )-Or a phenylene group (hereinafter, the phenylene group may be described as "-Ph-". The phenylene group includes 1,2-, 1,3- and 1,4-phenylene groups). Represents. Where Z ² Is a hydrogen atom or an optionally substituted aliphatic group having 1 to 8 carbon atoms (for example, methyl group, ethyl group, propyl group, butyl group, 2-chloroethyl group, 2-bromoethyl group, 2-cyanoethyl group, 2-hydroxyethyl group, benzyl group, chlorobenzyl group, methylbenzyl group, methoxybenzyl group, phenethyl group, 3-phenylpropyl group, dimethylbenzyl group, fluorobenzyl group, 2-methoxyethyl group, 3-methoxypropyl group, etc. ).
[0059]
Q ² Is a hydrogen atom or an optionally substituted aliphatic group having 1 to 6 carbon atoms (for example, methyl group, ethyl group, propyl group, butyl group, 2-chloroethyl group, 2,2-dichloroethyl group, 2,2, 2-trifluoroethyl group, 2-bromoethyl group, 2-hydroxyethyl group, 2-hydroxypropyl group, 2,3-dihydroxypropyl group, 2-hydroxy-3-chloropropyl group, 2-cyanoethyl group, 3-cyano Propyl group, 2-nitroethyl group, 2-methoxyethyl group, 2-methanesulfonylethyl group, 2-ethoxyethyl group, 3-bromopropyl group, 4-hydroxybutyl group, 2-furfurylethyl group, 2-thienylethyl Group, 2-carboxyethyl group, 3-carboxypropyl group, 4-carboxybutyl group, 2-carboxyamidoethyl group, 3-sulfo Midopuropiru group, 2-N- methyl-carboxamide ethyl group, cyclopentyl group, chlorocyclohexyl group, a dichlorohexyl group).
[0060]
d ¹ And d ² May be the same or different from each other, preferably a hydrogen atom, a halogen atom (eg, chlorine atom, bromine atom, etc.), a cyano group, an alkyl group having 1 to 3 carbon atoms (eg, methyl group, ethyl group, propyl group, etc.) ), -COO-L ¹ Or -CH ₂ -COO-L ¹ [L here ¹ Represents a hydrogen atom or an optionally substituted hydrocarbon group having 10 or less carbon atoms (for example, an alkyl group, an alkenyl group, an aralkyl group, an aryl group, etc.).
[0061]
Specific examples of the monomer (M) include vinyl esters or allyl esters of aliphatic carboxylic acids having 1 to 6 carbon atoms (acetic acid, propionic acid, butyric acid, monochloroacetic acid, trifluoropropionic acid, etc.); acrylic C1-C4 substituted alkyl esters or amides of unsaturated carboxylic acids such as acids, methacrylic acid, crotonic acid, itaconic acid, maleic acid (alkyl groups such as methyl, ethyl, propyl) Butyl group, 2-chloroethyl group, 2-bromoethyl group, 2-hydroxyethyl group, 2-cyanoethyl group, 2-nitroethyl group, 2-methoxyethyl group, 2-methanesulfonylethyl group, 2-benzenesulfonylethyl group, 2-carboxyethyl group, 4-carboxybutyl group, 3-chloropropyl group, 2-hydroxy-3 Chloropropyl group, 2-furfurylethyl group, 2-thienylethyl group, 2-carboxyamidoethyl group, etc.); styrene derivatives (for example, styrene, vinyltoluene, α-methylstyrene, vinylnaphthalene, chlorostyrene, dichlorostyrene, Bromostyrene, vinylbenzenecarboxylic acid, vinylbenzenesulfonic acid, chloromethylstyrene, hydroxymethylstyrene, methoxymethylstyrene, vinylbenzenecarboxamide, vinylbenzenesulfoamide, etc.); acrylic acid, methacrylic acid, crotonic acid, maleic acid, itacone Unsaturated carboxylic acids such as acids; cyclic acid anhydrides of maleic acid and itaconic acid; acrylonitrile; methacrylonitrile; a heterocyclic compound containing a polymerizable double bond group (specifically, for example, “Polymer” Data Nd book-Basic edition ", p. 175-184, compounds described in Yabu Fu (1986), for example, N-vinyl pyridine, N-vinyl imidazole, N-vinyl pyrrolidone, vinyl thiophene, vinyl tetrahydrofuran, vinyl oxazoline, vinyl Thiazole, N-vinylmorpholine, etc.).
The monomer (M) contains as a main component at least one monomer selected from the above.
[0062]
In the present invention, the compound of the general formula —N (R ¹ ) (R ² A basic monomer (B) containing an amino group represented by
R ¹ , R ² Each may be the same or different, preferably a hydrogen atom or an optionally substituted alkyl group having 1 to 22 carbon atoms (for example, methyl group, ethyl group, propyl group, butyl group, hexyl group, heptyl group, octyl group) Group, nonyl group, decyl group, dodecyl group, tridecyl group, tetradecyl group, hexadecyl group, octadecyl group, eicosyl group, docosyl group, 2-chloroethyl group, 2-bromoethyl group, 2-cyanoethyl group, 2-methoxycarbonylethyl group 2-methoxyethyl group, 3-bromopropyl group, etc.), an alkenyl group having 4 to 18 carbon atoms which may be substituted (for example, 2-methyl-1-propenyl group, 2-butenyl group, 2-pentenyl group, 3-methyl-2-pentenyl group, 1-pentenyl group, 1-hexenyl group, 2-hexenyl group, 4-methyl-2-hexenyl group Nyl group, decenyl group, dodecenyl group, tridecenyl group, hexadecenyl group, octadecenyl group, linoleyl group, etc.), an aralkyl group having 7 to 12 carbon atoms which may be substituted (for example, benzyl group, phenethyl group, 3-phenylpropyl group) Naphthylmethyl group, 2-naphthylethyl group, chlorobenzyl group, bromobenzyl group, methylbenzyl group, ethylbenzyl group, methoxybenzyl group, dimethylbenzyl group, dimethoxybenzyl group, etc.), substituted with 5 to 8 carbon atoms May be an alicyclic group (for example, cyclohexyl group, 2-cyclohexylethyl group, 2-cyclopentylethyl group, etc.) or an aromatic group having 6 to 12 carbon atoms (for example, phenyl group, naphthyl group, tolyl). Group, xylyl group, propylphenyl group, butylphenyl group, octylpheny Group, dodecylphenyl group, methoxyphenyl group, ethoxyphenyl group, butoxyphenyl group, decyloxyphenyl group, chlorophenyl group, dichlorophenyl group, bromophenyl group, cyanophenyl group, acetylphenyl group, methoxycarbonylphenyl group, ethoxycarbonylphenyl group , Butoxycarbonylphenyl group, acetamidophenyl group, propioamidophenyl group, dodeciloylamidophenyl group, etc.).
[0063]
R ¹ And R ² May form a ring, and specifically represents a ring-forming organic residue that may contain a hetero atom (for example, an oxygen atom, a nitrogen atom, a sulfur atom, etc.). Examples of the cyclic amino group to be formed include morpholino group, piperidino group, pyridinyl group, imidazolyl group, quinolyl group and the like. A plurality of these amino groups may be contained in the basic monomer molecule.
The colored resin particles of the present invention are particles of particles dispersed in a non-aqueous solvent by using an amino group-containing basic monomer (B) as a copolymerization component so that the surface of the particles themselves is positively charged. Dispersion stability is improved. This is presumably due to the charge repulsion effect when the particles are close to each other.
The basic monomer (B) is preferably used in an amount of 1 to 45% by weight, more preferably 3 to 30% by weight, based on the total amount of the monomer (M).
Specific examples of the basic monomer (B) are shown below, but the scope of the present invention is not limited thereto.
[0064]
[Chemical 6]

[0065]
In the present invention, -PO copolymerizable with the monomer (M). ₃ H ₂ Group, -SO ₃ H group and -SO ₂ An acidic monomer (A) containing at least one acidic group selected from H groups may be further used in combination. The acidic monomer (A) may contain a plurality of the acidic groups in the molecule. By using the acidic monomer (A) as a copolymerization component, the colored resin particles of the present invention can develop the surface of the particles themselves as negatively charged, and the dispersion stability of the particles dispersed in a non-aqueous solvent. Improve. The acidic monomer (A) is preferably used in an amount of 1 to 45% by weight, more preferably 3 to 30% by weight, based on the total amount of the monomer (M).
[0066]
Specific examples of the acidic monomer (A) are shown below. The present invention is not limited to these (in the following specific examples, Y represents —SO ₃ H group and -SO ₂ H group or -PO ₃ H ₂ Or -OPO ₃ H ₂ Represents a group).
[0067]
[Chemical 7]

[0068]
[Chemical 8]

[0069]
In the present invention, a monomer (L) having a long-chain aliphatic group that can be copolymerized with the monomer (M) may be further used in combination. In the monomer (L) having a long-chain aliphatic group, the long-chain aliphatic group represents an aliphatic group having 7 or more carbon atoms. Specific examples in that case include an aliphatic group having 10 to 32 carbon atoms in total (the aliphatic group may contain a substituent such as a halogen atom, a hydroxyl group, an amino group, an alkoxy group, or an oxygen atom, Acrylic acid, α-fluoroacrylic acid, α-chloroacrylic acid, α-cyanoacrylic acid, methacrylic acid having a hetero atom such as a sulfur atom or a nitrogen atom, and a carbon-carbon bond of the main chain thereof may be interposed , Esters of unsaturated carboxylic acids such as crotonic acid, maleic acid, itaconic acid (eg aliphatic groups such as decyl, dodecyl, tridecyl, tetradecyl, hexadecyl, octadecyl, docosyl, dodecenyl, hexadecenyl Groups, oleyl groups, linoleyl groups, dococenyl groups, etc.); amides of the above unsaturated carboxylic acids (as aliphatic groups) Examples of the higher fatty acid vinyl esters or allyl esters (higher fatty acids such as lauric acid, myristic acid, stearic acid, oleic acid, linoleic acid, behenic acid, etc.) And vinyl ethers in which an aliphatic group having 8 to 32 carbon atoms is bonded to an oxygen atom (the aliphatic group is the same as the aliphatic group exemplified in the above unsaturated carboxylic acid esters) And the like.
[0070]
By using the monomer (L) having a long-chain aliphatic group, the dispersion stability and redispersibility of the colored resin particles are further improved. This is because the copolymer component corresponding to the monomer (L) is oriented to the particle surface part due to its high solvophilicity with the solvent, and thus the solvophilicity with the solvent on the surface of the particle itself. It is presumed to increase and suppress aggregation and precipitation of particles. The usage-amount in the case of using a monomer (L) is 0.5 to 20 weight% in all the monomers, Preferably it is 1 to 15 weight%.
[0071]
Next, the dispersion stabilizer (P) will be described.
The dispersion stabilizer (P) is soluble in the non-aqueous solvent and is soluble in the non-aqueous solvent represented by the general formula (I), and a polymer repeat represented by the general formula (II). The main component is a polymer component B having a polymerizable double bond group at the terminal of the component substituent.
In the repeating unit represented by the general formula (I) constituting the polymer component A, X ⁰ Is preferably -COO-, -OCO-, -O-.
Q ⁰ Represents a linear or branched alkyl or alkenyl group having 4 to 22 carbon atoms. Specifically, butyl group, heptyl group, hexyl group, octyl group, dodecyl group, tridecyl group, tetradecyl group, hexadecyl group, octadecyl group, eicosanyl group, hexenyl group, octenyl group, decenyl group, dodecenyl group, hexadecenyl group, An octadecenyl group, a linolel group, etc. are mentioned.
[0072]
a ¹ And a ² May be the same as or different from each other, preferably a hydrogen atom, a halogen atom (for example, a chlorine atom or a bromine atom), a cyano group, an alkyl group having 1 to 3 carbon atoms (for example, a methyl group, an ethyl group, or a propyl group) Etc.), -COO-Z ¹ Or -COO-Z via hydrocarbon ¹ (Z ¹ Represents a hydrogen atom or an optionally substituted hydrocarbon group. Z ¹ Represents a hydrogen atom or an alkyl group, alkenyl group, aralkyl group, alicyclic group, aryl group or bridged cyclic hydrocarbon group having 1 to 22 carbon atoms, which may be substituted.
[0073]
Z ¹ The preferred hydrocarbon group is an alkyl group having 1 to 22 carbon atoms which may be substituted (for example, methyl group, ethyl group, propyl group, butyl group, heptyl group, hexyl group, octyl group, nonyl group, decyl group). , Dodecyl group, tridecyl group, tetradecyl group, hexadecyl group, octadecyl group, eicosanyl group, docosanyl group, 2-chloroethyl group, 2-bromoethyl group, 2-cyanoethyl group, 2-methoxycarbonylethyl group, 2-methoxyethyl group, 3-bromopropyl group and the like), an alkenyl group having 4 to 18 carbon atoms which may be substituted (for example, 2-methyl-1-propenyl group, 2-butenyl group, 2-pentenyl group, 3-methyl-2-pentenyl) Group, 1-pentenyl group, 1-hexenyl group, 2-hexenyl group, 4-methyl-2-hexenyl group, decenyl group A dodecenyl group, a tridecenyl group, a hexadecenyl group, an octadecenyl group, a linolel group, etc.), an aralkyl group having 7 to 12 carbon atoms which may be substituted (for example, a benzyl group, a phenethyl group, a 3-phenylpropyl group, a naphthylmethyl group, 2 -Naphthylethyl group, chlorobenzyl group, bromobenzyl group, methylbenzyl group, ethylbenzyl group, methoxybenzyl group, dimethylbenzyl group, dimethoxybenzyl group, etc.), C5-C8 optionally substituted alicyclic group (For example, a cyclohexyl group, 2-cyclohexylethyl group, 2-cyclopentylethyl group, etc.) and an aromatic group having 6 to 12 carbon atoms which may be substituted (for example, phenyl group, naphthyl group, tolyl group, xylyl group, Propylphenyl group, butylphenyl group, octylphenyl group, dodecylphenyl Group, methoxyphenyl group, ethoxyphenyl group, butoxyphenyl group, decyloxyphenyl group, chlorophenyl group, dichlorophenyl group, bromophenyl group, cyanophenyl group, acetylphenyl group, methoxycarbonylphenyl group, ethoxycarbonylphenyl group, butoxycarbonylphenyl Group, acetamidophenyl group, propioamidophenyl group, dodecyloylamidophenyl group, etc.) or a bridged cyclic hydrocarbon group having 5 to 18 carbon atoms (for example, bicyclo [1,1,0] butane, bicyclo [3 , 2,1] octane, bicyclo [5,2,0] nonane, bicyclo [4,3,2] undecane, adamantane and the like.
[0074]
In the repeating unit represented by the general formula (II) constituting the polymer component B, X ¹ Preferred examples of are: —COO—, —OCO—, —CON (Z ² )-And the like. X ³ Preferred examples of are -COO- and -COO (CH ₂ )-, -O- and the like.
W is a linking group X ¹ And linking group X ³ Represents a group consisting of at least one carbon atom, oxygen atom, sulfur atom, silicon atom or nitrogen atom, and specific examples thereof are shown below.
[0075]
[Chemical 9]

[0076]
G ¹ , G ² Each represents a hydrogen atom, a halogen atom (eg, fluorine atom, chlorine atom, bromine atom), a cyano group, a hydroxyl group, an alkyl group (eg, methyl group, ethyl group, propyl group).
G ³ , G ⁴ , G ⁵ Are each a hydrogen atom, a hydrocarbon group having 1 to 8 carbon atoms (for example, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, benzyl group, phenethyl group, phenyl group, tolyl group, etc.) or -OG ⁵ (G ⁵ Is G ³ Which is synonymous with the hydrocarbon group in FIG.
[0077]
Replacement of the polymer component A soluble in the non-aqueous solvent represented by the general formula (I) and the polymer repeating component represented by the general formula (II), which are constituents of the dispersion stabilizer (P) of the present invention Preferred examples of the polymer component B having a polymerizable double bond group at the end of the group are given below. Furthermore, although the preferable example of the dispersion stabilizer (P) of this invention is also given below, the scope of the present invention is not limited to this.
[0078]
[Chemical Formula 10]

[0079]
Embedded image

[0080]
Embedded image

[0081]
Embedded image

[0082]
The dispersion stabilizer (P) of the present invention can be easily synthesized by a conventionally known synthesis method.
That is, a bifunctional compound corresponding to the polymer component A represented by the general formula (I) and the polymer component B represented by the general formula (II) and having different polymerization reactivity in the radical polymerization reaction. By using a monomer and carrying out a polymerization reaction according to the method described in JP-A No. 60-185959, it can be synthesized without causing a gelation reaction.
[0083]
As a method for introducing a polymerizable double bond group into the resin, it can be synthesized by the method described in JP-A No. 61-43757. Specifically, in the polymer component B represented by the general formula (II), a polymerizable double bond group: -X ³ -C (c ¹ ) = CH (c ² ) Instead of a specific reactive group (for example, -OH, -COOH, -SO ₃ H, -NH ₂ , -SH, -PO ₃ H ₂ , -NCO, -NCS, -COCl, -SO ₂ Cl, an epoxy group, and the like are subjected to a polymerization reaction together with a monomer corresponding to the polymer component A represented by the general formula (I), and then the polymerizable double bond group described above Examples thereof include a method of introducing a polymerizable double bond group by a polymer reaction by reacting a contained reactive reagent.
[0084]
In the dispersion stabilizer (P), the proportion of the polymer component B represented by the general formula (II) having a polymerizable double bond group is usually 0.5 to 30 weights in 100 parts by weight of the total polymer. %, Preferably 1 to 10% by weight. Within this range, during the polymerization granulation reaction, gelation due to the crosslinking reaction of the reaction mixture does not occur, and a dispersion stabilizer (P) having a polymerizable double bond group can be obtained.
[0085]
The dispersion stabilizer (P) used in the present invention may contain other repeating units as a copolymerization component together with the repeating units of the general formulas (I) and (II). The other copolymer component may be any compound as long as it is composed of a monomer copolymerizable with a monomer corresponding to each repeating unit of the general formulas (I) and (II).
[0086]
The weight average molecular weight (Mw) of the dispersion stabilizer (P) of the present invention is 5 × 10. ³ ~ 1x10 ⁶ Is preferred, more preferably 2 × 10 ⁴ ~ 3x10 ⁵ It is.
[0087]
In order to produce colored resin particles encapsulating the colorant used in the present invention, the colored component surface-treated in a non-aqueous solvent is dispersed into fine particles to form seed particles. A polymerization system in which a dispersion stabilizer (P) having a polymerizable double bond group is added to the terminal of a substituent of a component is converted into benzoyl peroxide, azobis (2,4-dimethylvaleronitrile), azobis (4-methoxy- 2,4-dimethylvaleronitrile), azobisisobutyronitrile, butyllithium or the like may be polymerized in the presence of a polymerization initiator.
[0088]
Dispersion stabilizer having a polymerizable double bond group at the terminal of the substituent of the monomer and polymer repeating component in which the colored component surface-treated in a non-aqueous solvent is dispersed into fine particles to form seed particles To specifically add (P) and a polymerization initiator,
(1) A method of dropping a solution in which a monomer, a dispersion stabilizer (P), and a polymerization initiator are mixed and dissolved in a non-aqueous solvent, or a method of adding all at once or dividedly,
(2) Add a solution in which the dispersion stabilizer (P) is dissolved in the seed particles by dispersing the coloring component in a fine particle in a non-aqueous solvent, and then add the monomer and the polymerization initiator dropwise, or A method of adding in batches or divided,
(3) A solution in which a monomer, a dispersion stabilizer (P), and a polymerization initiator are mixed and dissolved in a non-aqueous solvent while the coloring component is dispersed in the form of fine particles in a non-aqueous solvent to form seed particles. A part is added, and after dispersion polymerization, a method of arbitrarily adding a mixture of the remaining monomer, dispersion stabilizer (P), and polymerization initiator,
(4) Disperse coloring components in a non-aqueous solvent in the form of fine particles to form seed particles, and add a part of the monomer to promote monomer absorption into the seed particles, and then the remaining monomer and dispersion A method in which the stabilizer (P) and the polymerization initiator are added dropwise, or collectively or dividedly.
Any of these methods can be used for manufacturing.
[0089]
Next, the amount of each component forming the colored resin particles encapsulating the colorant will be described. The use ratio of the seed particles (colored component fine particles) and the monomer {(M) and, if necessary, the total amount of (B), (A) and / or (L)} is 5/95 to 95/5. The weight ratio is preferred, more preferably 10/90 to 80/20 weight ratio. The total amount of monomers is about 5 to 80 parts by weight, preferably 10 to 50 parts by weight, per 100 parts by weight of the non-aqueous solvent. The dispersion stabilizer (P) having a polymerizable double bond group at the terminal of the substituent of the polymer repeating component dispersed in a soluble or colloidal form is based on 100 parts by weight of the total monomer used above. 1 to 100 parts by weight, preferably 3 to 50 parts by weight. The amount of the polymerization initiator is suitably 0.1 to 5 mol% of the total monomers. The polymerization temperature is about 20 to 180 ° C, preferably 30 to 120 ° C. The reaction time is preferably 1 to 15 hours.
[0090]
When aromatic hydrocarbons such as toluene and xylene remain in the non-aqueous solvent used in the reaction, and when polar solvents such as alcohols, ketones, ethers and esters described above are used in combination, or When unreacted monomers remaining to be granulated remain, it is preferably removed by heating to a boiling point or higher of the solvent or monomer, or by distilling off under reduced pressure.
[0091]
The non-aqueous pigment-encapsulating resin particles produced as described above have a discharge stability that does not cause clogging at the nozzle portion because the colorant is uniformly dispersed in fine particles and the dispersion stability of the dispersion is excellent. An oil-based ink for an inkjet printer is provided. Further, it has excellent drying properties on recording paper, water resistance and light resistance of recorded images, and has a high degree of scratch resistance. Furthermore, it is possible to easily obtain colorant-encapsulating resin particles that are uniformly dispersed in a non-aqueous solvent in a fine particle, and to control the charge polarity, the oil-based pigment ink for inkjet printers that is excellent in the stability of charge over time, and its inexpensive A manufacturing method is provided. Moreover, it has the characteristic that functions, such as fixing property and charge property, can be introduce | transduced into a colorant inclusion resin particle by selecting a monomer appropriately.
[0092]
Various additives may be added to the ink composition of the present invention as desired. The ink composition is arbitrarily selected depending on the material and structure of the ink jet system or the ink jet discharge head, the ink supply unit, and the ink circulation unit, and is contained as an ink composition.
For example, it is described in Takeshi Amari “Inkjet Printer-Technology and Materials”, Chapter 17, published by CMC Co., Ltd. (1998).
[0093]
Specifically, fatty acids (for example, monocarboxylic acid having 6 to 32 carbon atoms, polybasic acid; for example, 2-ethylhexynoic acid, dodecenyl succinic acid, butyl succinic acid, 2-ethylcaproic acid, lauric acid, palmitic acid, elaidin Acid, linolenic acid, ricinoleic acid, oleic acid, stearic acid, enanthic acid, naphthenic acid, ethylenediaminetetraacetic acid, abietic acid, dehydroabietic acid, hydrogenated rosin etc.), resin acid, alkylphthalic acid, alkylsalicylic acid, etc. (As metals of metal ions, Na, K, Li, B, Al, Ti, Ca, Pb, Mn, Co, Zn, Mg, Ce, Ag, Zr, Cu, Fe, Ba, etc.), surface active compounds (For example, as organic phosphoric acid or salts thereof, mono-, di- or trialkyl phosphoric acid composed of an alkyl group having 3 to 18 carbon atoms, etc. Organic sulfonic acids or salts thereof include long-chain aliphatic sulfonic acids, long-chain alkylbenzene sulfonic acids, dialkylsulfosuccinic acids and the like or metal salts thereof, and amphoteric surfactant compounds include phospholipids such as lecithin and kephalin), fluorine Alkyl group-containing surfactants containing atomic and / or dialkylsiloxane bonding groups, aliphatic alcohols (for example, higher alcohols comprising branched alkyl groups having 9 to 20 carbon atoms, benzyl alcohol, phenethyl alcohol, cyclohexyl) Alcohols), polyhydric alcohols {for example, alkylene glycols having 2 to 18 carbon atoms (ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, neopentyl glycol, 1, 6-hexanedio , Dodecanediol, etc.); C4-C1000 alkylene ether glycol (diethylene glycol, triethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, etc.); C5-C18 alicyclic Diol (1,4-cyclohexanedimethanol, hydrogenated bisphenol A, etc.); C12-C23 bisphenols (bisphenol A, bisphenol F, bisphenol S, etc.) C2-C18 alkylene oxide (ethylene oxide, propylene) Oxide, butylene oxide, α-olefin oxide, etc.) adduct, glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, sorbitol Polyols such as trihydric to octahydric or higher (trisphenol PA, phenol novolak, cresol novolak, etc.); C 2-18 alkylene oxide adducts (addition moles) of the above trivalent or higher polyphenols 2 to 20), ether derivatives of polyhydric alcohols (polyglycol alkyl ethers, alkylaryl polyglycol ethers, etc.), fatty acid ester derivatives of polyhydric alcohols, ether oleate derivatives of polyhydric alcohols (for example, ethylene glycol mono Ethyl acetate, diethylene glycol monobutyl acetate, propylene glycol monobutyl propiolate, sorbitan monomethyl dioxanolate, etc.), alkyl naphthalene sulfonate, alkyl aryl sulfonate, etc. Compounds including but not limited to.
[0094]
The amount of each additive used is preferably adjusted so that the surface tension of the ink composition is 15 to 60 mN / m (at 25 ° C.) and the viscosity is in the range of 1.0 to 40 cp.
[0095]
In addition, various charge control agents may be added to the liquid developer of the present invention as desired in order to enhance charge characteristics or improve image characteristics.
[0096]
Conventionally known charge control agents for liquid developers used in the present invention can be used. For example, metal salts of fatty acids such as naphthenic acid, octenoic acid, oleic acid, stearic acid, metal salts of sulfosuccinic acid esters, Japanese Patent Publication No. 45-556, Japanese Patent Publication No. 52-37435, Japanese Patent Publication No. 52-37049 Oil-soluble sulfonic acid metal salts shown in Japanese Patent Publication No. 4 and the like, phosphoric acid ester metal salts shown in Japanese Patent Publication No. 4 publication, metal of abietic acid or hydrogenated abietic acid shown in Japanese Patent Publication No. 48-25666 publication Salt, alkylbenzenesulfonic acid Ca salts disclosed in JP-B-55-2620, JP-A-52-107837, 52-38937, 57-90643, and 57-139753 Aromatic carboxylic acid or sulfonic acid metal salts, nonionic surfactants such as polyoxyethylated alkylamines, Fats and oils such as cystine and linseed oil, polyvinyl pyrrolidone, organic acid esters of polyhydric alcohol, phosphate ester surfactants disclosed in JP-A-57-210345, and JP-B-56-24944 The sulfonic acid resin etc. which are made can be used. In addition, amino acid derivatives described in JP-A-60-21056 and 61-50951 can also be used. Moreover, the copolymer etc. which contain the maleic acid half amide component described in each gazette of Unexamined-Japanese-Patent No. 60-173558 and 60-179750 are mentioned. Further, quaternized amine polymers described in JP-A-54-31739 and JP-B-56-24944 can be given.
[0097]
Among these, preferred are a metal salt of naphthenic acid, a metal salt of dioctylsulfosuccinic acid, a copolymer containing the maleic acid half amide component, lecithin, and the amino acid derivative. As these charge control agents, two or more compounds can be used in combination.
The charge control agent as described above is preferably 0.001 to 10.0 parts by weight with respect to 1000 parts by weight of the non-aqueous solvent. Further, various additives may be added if desired, and the upper limit of the total amount of these additives is regulated by the electric resistance of the developer. That is, the electric resistance of the liquid developer with the toner particles removed is 10 ⁹ If it is lower than Ωcm, it is difficult to obtain a high-quality continuous tone image, so it is necessary to control the amount of each additive within this limit.
[0098]
The following examples show that the ink composition of the present invention is useful as an oil-based ink for inkjet printers. As an ink jet printer, a piezoelectric method and an electrostatic method ink jet printer will be described as an example. However, the present invention is not limited to these methods, and the present invention can be applied to an ink jet printer represented by a slit jet such as a thermal method or NTT.
[0099]
The electrostatic ink jet printer will be further described.
1 and 2 are schematic diagrams for explaining an example of an ejection head. FIG. 1 is a diagram showing a configuration of a line scanning type multi-channel inkjet head, and shows a section of ejection electrodes corresponding to recording dots. In the drawing, ink 100 is supplied between a head substrate 102 and a discharge electrode substrate 103 from a circulation mechanism 111 including a pump through an ink supply channel 112 connected to the head block 101, and the ink formed in the head block 101 is also the same. The ink is recovered by the ink circulation mechanism 111 through the recovery channel 113. The discharge electrode substrate 103 includes an insulating substrate 104 having a through hole 107 and a discharge electrode 109 formed on the recording medium side around the through hole 107. On the other hand, a convex ink guide 108 is disposed on the head substrate 102 at a substantially central position of the through hole 107. The convex ink guide 108 is made of an insulating member such as plastic resin or ceramics, and is arranged at the same row interval and pitch so that the center is equal to the through hole 107, and is held on the head substrate 102 by a predetermined method. Yes. Each convex ink guide 108 has a shape in which the tip of a flat plate having a constant thickness is cut into a triangle or a trapezoid, and the tip becomes the ink droplet flying position 110. Each convex ink guide 108 may form a slit-like groove from the tip thereof, and the ink supply to the ink flying position 110 is smoothly performed by the capillary action of the slit, thereby improving the recording frequency. I can do it. In addition, any surface of the ink guide may have conductivity as required. In that case, the conductive portion is electrically floated so that the ink can be effectively applied with a small voltage applied to the ejection electrode. An electric field can be formed at the flight position. Each convex ink guide 108 protrudes in the ink droplet flying direction by a predetermined distance substantially perpendicularly from each through hole. A recording medium 121, which is a recording sheet, is disposed opposite to the tip of the convex ink guide 108, and a counter electrode that also serves as a platen for guiding the recording medium 121 on the back surface of the recording medium 121 opposite to the head substrate 102. 122 is arranged. In addition, a migration electrode 140 is formed at the bottom of the space formed between the head substrate 102 and the ejection electrode substrate 103. By applying a predetermined voltage to the migration electrode 140, the migration of the ink in the ink guide in the ejection position direction is performed. Charged particles can be electrophoresed to increase ejection responsiveness.
[0100]
Next, a specific configuration example of the discharge electrode substrate 103 will be described with reference to FIG. FIG. 2 is a view of the discharge electrode substrate 103 as viewed from the recording medium 121 side. A plurality of discharge electrodes are arranged in an array in two rows in the main scanning direction, and a through hole 107 is formed at the center of each discharge electrode. In addition, individual discharge electrodes 109 are formed around the through-holes 107, respectively. In this embodiment, the inner diameter of the discharge electrode 109 is set to be slightly larger than the diameter of the through hole 107, but it may be the same as the diameter of the through hole 107. Here, the insulating substrate 104 is made of polyimide having a thickness of about 25 to 200 μm, the discharge electrode 109 is made of copper foil having a thickness of about 10 to 100 μm, and the inner diameter of the through hole 107 is about 150 to 250 μmΦ.
[0101]
Next, the recording operation of the electrostatic ink jet recording apparatus will be described. Here, a case where positively charged ink is used will be described as an example, but the present invention is not limited to this example. At the time of recording, the ink 100 supplied from the ink circulation mechanism 111 via the ink supply channel 112 is supplied from the through hole 107 to the ink flying position 110 at the tip of the convex ink guide 108, and a part of the ink recovery channel. The ink is recovered by the ink circulation mechanism 111 through 113. Here, a voltage of, for example, +1.5 kV is applied as a bias from the bias voltage source 123 to the ejection electrode 109, and a pulse voltage of, for example, +500 V is applied as a signal voltage corresponding to the image signal from the signal voltage source 124 to the discharge electrode 109. Superposed on the discharge voltage 109. At this time, a voltage of +1.8 kV is applied to the migration electrode 140. On the other hand, the counter electrode 122 provided on the back surface of the recording medium 121 is set to a ground voltage of 0 V as shown in the figure. In some cases, the recording medium 121 side may be charged to, for example, −1.5 kV to obtain a bias voltage. In this case, an insulating layer is provided on the surface of the counter electrode 122, the recording medium is charged by a corona charger, a scorotron charger, a solid ion generator or the like, and the discharge electrode 109 is grounded, for example, and a signal voltage source 124 is connected thereto. As a signal voltage corresponding to the image signal from, for example, a pulse voltage of +500 V is superimposed on the ejection voltage 109 at the time of ON. At this time, a voltage of +200 V is applied to the migration electrode 140. Now, when the discharge voltage 109 is in an ON state (a state in which 500 V is applied) and a voltage of 2 kV in total, in which a 500 V pulse voltage is superimposed on the bias DC 1.5 kV, is applied, the ink droplet flying position 110 at the tip of the convex electrode 108 is applied. Then, the ink droplet 115 is ejected, pulled in the direction of the counter electrode 122, and ejected toward the recording medium 121 to form an image.
[0102]
In order to improve the accuracy of landing on the recording medium by precisely controlling the flying of the ink droplets after the flight, an intermediate electrode is provided between the ejection electrode and the recording medium, or a guard electrode for suppressing electric field interference between the ejection electrodes. Of course, a means such as providing the above is used, but it should be understood that the present embodiment can be suitably used in this embodiment as needed. Further, a porous body may be provided between the head base plate 102 and the discharge electrode substrate 103. In this case, it is possible to prevent the influence of the change in the ink internal pressure due to the movement of the ink jet head and the like, and the through hole after the ink droplet discharge Ink liquid supply to 107 parts is quickly achieved. Therefore, the flying of the ink droplet 115 is stabilized, and a good image with a stable density can be recorded on the recording medium 121 at high speed.
[0103]
【Example】
Examples of the present invention will be described below.
Synthesis Example of Dispersion Stabilizer 1: Synthesis of (P-1) (Compound Example (a))
A mixed solution of 96.7 g of lauryl methacrylate, 2.2 g of vinyl methacrylate and 400 g of isodecane was heated to a temperature of 70 ° C. under a nitrogen stream. Under stirring, 1.0 g of 2,2′-azobis (butyronitrile) was added and reacted for 3 hours, and 1.0 g of 2,2′-azobis (butyronitrile) was further added and reacted for 4 hours. The solid content concentration of the obtained solution was 19%.
A weight-average molecular weight measured by high-performance liquid chromatography of a colorless and transparent viscous product obtained by adding 1 part of the reaction solution into a 10-fold amount of methanol solvent was 3.8 × 10 ⁴ Met.
[0104]
Synthesis Example 2 of Dispersion Stabilizer: Synthesis of (P-2) (Compound Example (b))
A mixed solution of stearyl methacrylate 128.7 g, vinyl methacrylate 2.2 g, and isodecane 300 g was heated to a temperature of 75 ° C. under a nitrogen stream. Thereafter, 1.3 g of 2,2′-azobis (butyronitrile) was added and stirred for 3 hours. Further, 1.3 g of 2,2′-azobis (butyronitrile) was added and reacted for 5 hours. The solid content concentration of the obtained solution was 30.0%. The weight average molecular weight of the white solid obtained by treatment as measured in Synthesis Example 1 was 3.5 × 10 ⁴ Met.
[0105]
Synthesis Example 3 of Dispersion Stabilizer: Synthesis of (P-3) (Compound Example (c))
A mixed solution of 71.0 g of lauryl methacrylate, 2.2 g of vinyloxycarbonylmethyloxy-carbonylethyl acrylate, and 293 g of isodecane was heated to a temperature of 70 ° C. under a nitrogen stream. Thereafter, 1.1 g of 2,2′-azobis (butyronitrile) was added and stirred for 3 hours. Further, 1.1 g of 2,2′-azobis (butyronitrile) was added and reacted for 5 hours. The solid content concentration of the obtained solution was 19.6%. The weight average molecular weight of the white solid obtained by treatment as measured in Synthesis Example 1 was 3.5 × 10 ⁴ Met.
[0106]
Synthesis Example 4 of Dispersion Stabilizer: Synthesis of (P-4) (Compound Example (h))
A mixed solution of 59.0 g of hexadecyl acrylate, 3.1 g of allyloxycarbonyl decamethylene methacrylamide and 145 g of n-dodecane was heated to a temperature of 75 ° C. under a nitrogen stream. Thereafter, 0.9 g of 2,2′-azobis (butyronitrile) was added and stirred for 3 hours. Further, 0.9 g of 2,2′-azobis (butyronitrile) was added and reacted for 4 hours. The solid content concentration of the obtained solution was 29.4%. The weight-average molecular weight of the white solid measured and measured as in Synthesis Example 1 was 4.1 × 10 ⁴ Met.
[0107]
Synthesis Example 5 of Dispersion Stabilizer: Synthesis of (P-5) (Compound Example (i))
A mixed solution of 45.0 g of stearyl methacrylate, 1.7 g of vinyloxyethyl acrylate, and 109 g of Isopar G was heated to a temperature of 75 ° C. under a nitrogen stream. Thereafter, 0.7 g of benzoyl peroxide was added and stirred for 3 hours. Further, 0.7 g of benzoyl peroxide was added and reacted for 4 hours. The solid content concentration of the obtained solution was 29.0%. The weight-average molecular weight of the white solid obtained by treatment and measurement as in Synthesis Example 1 was 3.8 × 10 ⁴ Met.
[0108]
Synthesis Examples 6-12 of Dispersion Stabilizer: Synthesis of (P-6) to (P-12)
A predetermined amount of each monomer described in the following Table-A and a mixed solution of 250 g of Isopar G were heated to a temperature of 65 ° C. under a nitrogen stream. Thereafter, 1.0 g of 2,2′-azobis (butyronitrile) was added and reacted for 4 hours, and 0.5 g of 2,2′-azobis (butyronitrile) was further added and reacted for 3 hours. After cooling, the solution was poured into 2 L of methanol solvent and reprecipitated, and the resulting precipitate was filtered and dried under reduced pressure at room temperature. The weight average molecular weight of each resin obtained was 4.0 × 10 ⁴ ~ 8.0 × 10 ⁴ Met.
[0109]
[Table 1]

[0110]
Synthesis Example 13 of Dispersion Stabilizer: Synthesis of (P-13) (Compound Example (l))
A mixed solution of 96.7 g of lauryl methacrylate, 5.4 g of hydroxycarbonyl decamethylene methacrylamide and 100 g of toluene was heated to a temperature of 70 ° C. under a nitrogen stream, and 1.0 g of 2,2′-azobis (butyronitrile) was stirred. Was added. After 6 hours, the mixture was cooled to 40 ° C. and 0.2 g of hydroquinone was added. Further, 6.9 g of vinyl acetate and 0.05 g of mercury acetate were added and reacted for 2 hours. The temperature was raised again to 70 ° C. and 7.5 × 10% 100% sulfuric acid ^-3 The reaction was continued until the carboxylic acid quantitative value derived from the methacrylamide monomer compound was reduced to 50%. After the reaction, 0.04 g of sodium acetate trihydrate was added to the reaction solution and stirred well, and then poured into 4000 g of methanol for reprecipitation purification to obtain a slightly brownish viscous product. The weight average molecular weight of this viscous material is 14.5 × 10 ⁴ Met.
[0111]
Synthesis Example 14 of Dispersion Stabilizer: Synthesis of (P-14) (Compound Example (k))
By using stearyl methacrylate 128.6 g instead of lauryl methacrylate used in Synthesis Example 13, the same operation as in Synthesis Example 13 was performed to obtain a slightly yellowish powder. The weight average molecular weight of this powder was 22.2 × 10 ⁴ Met.
[0112]
Synthesis Example 15 of Dispersion Stabilizer: Synthesis of (P-15) (Compound Example (m))
A mixed solution of 87.5 g of lauryl acrylate, 9.7 g of hydroxycarbonyl decamethylene methacrylamide and 120 g of Isopar E was heated to a temperature of 80 ° C. under a nitrogen stream, and 2,2′-azobis (butyronitrile) under stirring. 0 g was added. After 3 hours, 1.0 g of 2,2′-azobis (butyronitrile) was added again and reacted for 3 hours. After adding 0.2 g of hydroquinone, 11.4 g of vinyl acetate and 1.0 g of tetrabutoxy titanium are added at the same temperature, and the reaction is continued until the carboxylic acid quantitative value derived from the methacrylamide monomer compound is reduced to 50%. went. After the reaction, it was purified by reprecipitation from 4000 g of acetonitrile to obtain a slightly brownish viscous product. The weight average molecular weight is 10.3 × 10 ⁴ Met.
[0113]
Synthesis Example of Dispersion Stabilizer 16: Synthesis of (P-16) (Compound Example (o))
A mixed solution of 137.1 g of stearyl methacrylate, 11.0 g of hydroxycarbonyltrimethyleneoxy-carbonylethyl methacrylate, and 300 g of toluene was heated to a temperature of 70 ° C. in a nitrogen stream, and 2,2′-azobis (butyronitrile) 1 under stirring. .5 g was added. After 6 hours, the mixture was cooled to 40 ° C. and 0.5 g of hydroquinone was added. Further, 31.0 g of vinyl acetate and 0.2 g of mercury acetate were added and reacted for 2 hours. The temperature was raised again to 70 ° C. and 100% sulfuric acid 3.4 × 10 ^-2 The reaction was continued until the carboxylic acid quantitative value derived from the acid-containing methacrylate monomer compound was reduced to 35%. After the reaction, 0.2 g of sodium acetate trihydrate was added to the reaction solution and stirred well, and then reprecipitated and purified in the same manner as in Synthesis Example 13 to obtain a white powder. The weight average molecular weight is 29.5 × 10 ⁴ Met.
[0114]
Synthesis Example 17 of Dispersion Stabilizer: Synthesis of (P-17) (Compound Example (n))
A mixed solution of 105.6 g of hexadecyl methacrylate, 6.7 g of hydroxycarbonyltrimethyleneoxy-carbonylethyl methacrylate, and 200 g of Isopar E is heated to a temperature of 70 ° C. in a nitrogen stream, and 2,2′-azobis (butyronitrile) is stirred. 1.6g was added. After 6 hours, the mixture was cooled to 40 ° C. and 0.2 g of hydroquinone was added. Further, 25.0 g of vinyl acetate and 3 g of tetrabutoxytitanium were added, the temperature was raised again to 70 ° C., and the reaction was continued until the carboxylic acid quantitative value derived from the acid-containing methacrylate monomer compound was reduced to 50%. After the reaction, reprecipitation purification was performed in the same manner as in Synthesis Example 13 to obtain a slightly yellowish viscous product. The weight average molecular weight is 28.7 × 10 ⁴ Met.
[0115]
Synthesis Example 18 of Dispersion Stabilizer: Synthesis of (P-18) (Compound Example (p))
A mixed solution of 105.6 g of hexadecyl methacrylate, 64.7 g of hydroxycarbonyl decamethylene methacrylamide, and 400 g of Isopar E was heated to a temperature of 80 ° C. under a nitrogen stream, and 2,2′-azobis (butyronitrile) 1. 6 g was added. After 6 hours, 0.1 g of hydroquinone was added, the temperature was raised to 110 ° C., 58.1 g of allyl alcohol and 0.5 g of concentrated sulfuric acid were added, and the reaction was carried out while removing the distilled water with the Dean Stark apparatus. . The reaction was stopped when the carboxylic acid quantitative value derived from the methacrylamide monomer compound decreased to 35%, and reprecipitation purification was performed in the same manner as in Synthesis Example 13 to obtain a slightly brownish viscous product. The weight average molecular weight is 19.7 × 10 ⁴ Met.
[0116]
Example 1
<Preparation of pigment dispersion>
A 20% solution prepared by dissolving a pigment dispersant (D-1) having the following structure in Isopar H by heating was used as a pigment dispersant. 88.25 parts by weight of the pigment dispersant solution, 17.65 parts by weight of Microlith Black CT (manufactured by Ciba Specialty Chemicals) treated with a rosin ester resin as a black processed pigment, 29.4 parts by weight of ISOPAR H The mixture was mixed with 250 parts by weight of glass beads with a paint shaker (Toyo Seiki KK) for 30 minutes. Next, the glass beads were separated by filtration, and then dispersed for 3 hours at a rotational speed of 3000 rpm using a high-speed dispersion mixing apparatus Dynomill (trade name; KDL). The media used glass beads MK-3GX. When the volume average particle diameter of the pigment particles in the dispersion was measured with an ultracentrifugal automatic particle size distribution analyzer CAPA700 (Horiba Seisakusho), it was well dispersed with 0.16 μm.
[0117]
Embedded image

[0118]
<Preparation of colored resin particles>
85.8 g of the filtrate (solid content 23.3%) of the processed pigment dispersion obtained by filtering the glass beads was placed in a four-necked flask and heated at a temperature of 80 ° C. for 3 hours with stirring under a nitrogen stream.
Next, in this processed pigment dispersion, 2 g of (P-1) as a dispersion stabilizer (P) as a powder, 22.0 g of methyl methacrylate, 28.0 g of methyl acrylate and 120 g of ISOPAR H are mixed in a mixed solution. , 2'-azobis (2,4-dimethylvaleronitrile) 1.0 g as a feed solution was added dropwise at a dropping rate of 2.5 ml / min, followed by reaction for 3 hours. About 20 minutes after the start of dropping, heat generation started, and the temperature of the reaction solution rose about 5 ° C. After the reaction for 3 hours, the temperature was raised to 90 ° C. and stirred for 2 hours to distill off unreacted monomers. The black resin particle dispersion obtained by passing through a 200-mesh nylon cloth after cooling had a polymerization rate of 97% and a volume average particle size of 0.24 μm. The resulting black resin particle dispersion was also good in dispersion after storage for 1 month.
When the black resin particle dispersion was observed with an S-800 field emission scanning electron microscope (manufactured by Hitachi Electric), microlith black pigment particles of about 100 nm grew into spherical resin particles of about 180 nm after dispersion polymerization. It was found that the dropped monomer was absorbed and polymerized in the seed pigment particles.
Further, when the black particle dispersion was observed with a transmission scanning electron microscope, it was found that the pigment particles of the seed were encapsulated in the spherical colored resin particles of about 180 nm after the dispersion polymerization.
From the above, it can be seen that the colored resin particles produced by the seed dispersion polymerization of the present invention are colored resin particles containing a rosin ester resin-treated pigment inside.
[0119]
<Preparation of Ink Composition (IJ-1)>
The colored resin particle dispersion is once concentrated by distilling off the solvent and diluted with Isopar G. The viscosity is 13 cp (E-type viscometer, measured at a temperature of 25 ° C.) and the surface tension is 23 mN / m (Kyowa Interface Science). An ink composition (IJ-1) of an automatic surface tension meter (measured at a temperature of 25 ° C.) was prepared. Using a color facsimile Saiyuki UX-E1CL (manufactured by Sharp Corporation) as an ink jet recording apparatus, filling the ink composition (IJ-1), and drawing on Fuji Photo Film Inkjet Paper High Grade Special Paper, nozzle clogging It was discharged stably. The obtained drawn image had no blur and was a good quality and clear image density of 1.8. Next, a full solid pattern was printed, and after the printed matter was dried, the solid portion was rubbed with a finger. As a result, it was found that there was no background stain at all and it was extremely excellent in scratch resistance. The ink composition did not exhibit sedimentation aggregation even after storage for a long period of time, had very good dispersibility, and could be used for continuous printing for a considerable period of time, giving excellent sharpness printing.
[0120]
Example 2
<Preparation of pigment dispersion>
100 parts by weight of carbon black # 30 (manufactured by Mitsubishi Chemical Corporation) as a black pigment, ethylene / stearyl acrylate copolymer (95/5 molar ratio) as a resin for polymer treatment, and 200 parts by weight were pre-ground with a trioblender and mixed well. Thereafter, the mixture was melt-kneaded (20 minutes) with a three-roll mill heated to 120 ° C. The pigment kneaded product was pulverized with a pin mill.
Next, 10 parts by weight of a pigment kneaded product, 65 parts by weight of Isopar H, 20 parts by weight of a 20 wt% solution prepared by dissolving and dissolving a pigment dispersant (D-2) having the following structure in Isopar H, and 3G-X glass beads The mixture was mixed with 250 parts by weight with a paint shaker (Toyo Seiki KK) for 60 minutes. Next, the glass beads were separated by filtration, and then dispersed for 3 hours at a rotational speed of 3000 rpm using a high-speed dispersion mixing apparatus Dynomill (trade name; KDL). The media used glass beads MK-3GX. When the volume average particle size of the pigment particles in the dispersion was measured with an ultracentrifugal automatic particle size distribution analyzer CAPA700 (Horiba Seisakusho), it was well dispersed as 0.16 μm.
[0121]
Embedded image

[0122]
<Preparation of colored resin particles>
214.3 g of the pigment dispersion filtrate (solid content: 14.0%) obtained by filtering the glass beads was placed in a four-necked flask and heated at 75 ° C. for 1 hour with stirring under a nitrogen stream. Next, in this pigment dispersion, as in Example 1, 4 g of dispersion stabilizer (P-2) in powder form, 6.0 g of methyl methacrylate, 14.0 g of methyl acrylate, and 80 g of Isopar H were mixed. A solution obtained by adding 0.5 g of 2,2′-azobis (2,4-dimethylvaleronitrile) to the solution was added dropwise as a feed solution over 1 hour, and then reacted for 3 hours. About 15 minutes after the start of dropping, heat generation started, and the temperature of the reaction solution rose about 4 ° C. After the reaction for 3 hours, the temperature was raised to 90 ° C., and the mixture was stirred for 2 hours while increasing the nitrogen flow rate to distill off the unreacted monomer. The black resin particle dispersion had a polymerization rate of 96.0% and a volume average particle size of 0.22 μm. The resulting black resin particle dispersion was also good in dispersion after storage for 1 month.
[0123]
<Preparation of ink composition (IJ-2)>
The colored resin particle dispersion was once concentrated by distilling off the solvent and diluted with Isopar G to prepare an ink composition (IJ-2) having a viscosity of 13 cp and a surface tension of 23 mN / m. When the ink composition (IJ-2) was printed in the same manner as in Example 1 with a color facsimile Saiyuki UX-E1CL (manufactured by Sharp Corporation), a clear print of good quality without bleeding was given. Further, when the scratch resistance was examined in the same manner as in Example 1, it was found that there was no background contamination and it was extremely excellent in scratch resistance. The ink composition had good dispersibility because it did not precipitate and agglomerate even when stored for a long time.
[0124]
Example 3
<Preparation of pigment dispersion>
After stirring 10 parts by weight of carbon black # 100 (manufactured by Mitsubishi Chemical Corporation) as a black pigment and 100 parts by weight of water with a flasher, a styrene / vinyltoluene / lauryl methacrylate copolymer (40/58/2 mol) was used as a polymer treatment resin. 60 parts by weight of a 33% toluene solution was added to a flasher and stirred. Subsequently, it heated and pressure-reduced, the water | moisture content and the solvent were removed, and the black lump thing of the moisture content 1 weight% was obtained. The black lump was vacuum-dried to completely remove water, and then pulverized with a sample mill to obtain a black powder of 0.1 to 0.01 mm. In Example 2, the above black powder was used in place of the pigment kneaded material, and the pigment dispersant (D-3) having the following structure was used in place of (D-2) as the pigment dispersant. The pigment dispersion was carried out in the same manner as described above. The black pigment dispersion obtained after filtering out glass beads had a volume average particle size of 0.13 μm and good dispersibility.
[0125]
Embedded image

[0126]
<Preparation of colored resin particles>
In Example 2, 4 g of (P-3) was used instead of the dispersion stabilizer (P-1) using the filtrate of the pigment dispersion obtained by filtering the glass beads (solid content: 13.0%) as seed particles. Otherwise, dispersion polymerization was performed in the same manner as in Example 2. The resulting black resin particle dispersion had a polymerization rate of 98.0% and a volume average particle size of 0.23 μm. The resulting black resin particle dispersion was also good in dispersion after storage for 1 month.
[0127]
<Preparation of ink composition (IJ-3)>
The pigment resin particle dispersion was adjusted to a viscosity of 13 cp and a surface tension of 23 mN / m to obtain an ink composition (IJ-3). When the ink composition (IJ-3) was printed in the same manner as in Example 1 with a color facsimile Saiyuki UX-E1CL (manufactured by Sharp Corporation), high-quality clear printing without blurring was given. Further, when the scratch resistance was examined in the same manner as in Example 1, it was found that there was no background contamination and it was extremely excellent in scratch resistance. The ink composition had good dispersibility because it did not precipitate and agglomerate even when stored for a long time.
[0128]
Comparative Example 1
<Preparation of comparative pigment dispersion>
5 parts by weight of alkali blue as a blue pigment, 5 parts by weight of lauryl methacrylate / acrylic acid copolymer (composition ratio 95/5 wt / wt) as a pigment dispersant, paint shaker (90 parts by weight of ISOPAR H and 250 parts by weight of glass beads) The mixture was mixed with Toyo Seiki KK) for 30 minutes. Next, the glass beads are separated by filtration, then dispersed with a high-speed dispersion mixing apparatus Dynomill (trade name; KDL) for 3 hours at a rotational speed of 3000 rpm, and the volume average particle size of the pigment particles in the dispersion is determined as an ultracentrifugal automatic particle size distribution. When measured with a measuring apparatus CAPA700 (Horiba Seisakusho), it was well dispersed with 0.13 μm.
[0129]
<Preparation of colored resin particles for comparison>
208.3 g of the pigment dispersion filtrate (solid content: 9.6%) obtained by filtering the glass beads was placed in a four-necked flask and heated at 80 ° C. for 3 hours while stirring under a nitrogen stream. Next, in this pigment dispersion, in the same manner as in Example 1, 6 g of the dispersion stabilizer (P-1), 12.0 g of methyl methacrylate, 28.0 g of methyl acrylate, and 120 g of Isopar H were added to a mixed solution. A solution obtained by adding 1.0 g of 2'-azobis (2,4-dimethylvaleronitrile) as a feed solution was added dropwise at a dropping rate of 2.5 ml / min, and then reacted for 3 hours. About 15 minutes after the start of dropping, heat generation started and the temperature of the reaction solution increased by about 5 ° C., but coarse particles adhered to the wall of the flask, and a large amount of precipitate was observed at the bottom of the flask after the reaction. . The colored resin particles of Comparative Example 1 could not be used for the next ink composition due to the generation of coarse particles and sediment.
[0130]
Comparative Examples 2-3
In Example 1, instead of the black pigment Microlith Black CT (Ciba Specialty Chemicals) treated with rosin ester resin, a blue pigment treated with the following polymer (CI Pigmet Blue 15: The pigment dispersion was performed in the same manner as in Example 1 except that 3) was used.

[0131]
The pigment dispersions of Comparative Examples 2-3 obtained by filtering glass beads after dispersion had a volume average particle size of 1.48 μm in Comparative Example 2 and 1.67 μm in Comparative Example 3. Since the pigment dispersion liquids of Comparative Examples 2 to 3 have coarse particles and precipitates are formed with the passage of time, the dispersibility is not good, so that the pigment dispersion liquids could not be used for the next seed polymerization.
[0132]
From Examples 1 to 3 and Comparative Examples 1 to 3, the pigment treated with the polymer as in the present invention is specifically made into fine particles and has good dispersion stability, and is also polymerizable as a dispersion stabilizer. Since the copolymer having a heavy bond group is used, the seed dispersion polymerization proceeds well, and the colored resin particles containing the polymer-treated pigment produced by the seed dispersion polymerization have a clear print image quality, extremely high It was found that the ink exhibits good ink properties such as excellent scratch resistance and good long-term dispersibility.
[0133]
Example 4
<Preparation of pigment dispersion>
100 parts by weight of carbon black # 30 (manufactured by Mitsubishi Chemical Corporation) as a black pigment, methyl methacrylate / stearyl methacrylate copolymer (9/1 molar ratio) as a resin for polymer treatment, 200 parts by weight are pre-ground with a trioblender and mixed well. Then, it was melt-kneaded (20 minutes) with a three-roll mill heated to 120 ° C. The pigment kneaded product was pulverized with a pin mill.
Next, 10 parts by weight of the pigment kneaded material, 65 parts by weight of Isopar G, and 25 parts by weight of a 20 wt% solution prepared by dissolving Solprene 1205 (produced by Asahi Kasei Co., Ltd., styrene / butadiene copolymer) as a pigment dispersant in Isopar G by heating. , And 250 parts by weight of 3G-X glass beads were mixed with a paint shaker (Toyo Seiki KK) for 60 minutes. Next, the glass beads were separated by filtration, and then dispersed for 3 hours at a rotational speed of 3000 rpm using a high-speed dispersion mixing apparatus Dynomill (trade name; KDL). The media used glass beads MK-3GX. When the volume average particle size of the pigment particles in the dispersion was measured with an ultracentrifugal automatic particle size distribution analyzer CAPA700 (Horiba Seisakusho), it was well dispersed as 0.21 μm.
[0134]
<Preparation of colored resin particles>
214.3 g of the pigment dispersion filtrate (solid content: 14.0%) obtained by filtering the glass beads was placed in a four-necked flask and heated at a temperature of 50 ° C. for 1 hour with stirring under a nitrogen stream. Next, in this pigment dispersion, 4 g of the above dispersion stabilizer (P-2) as a powder, 20.0 g of methyl acrylate and 80 g of Isopar H in a mixed solution of 2,2′-azobis (4-methoxy- 2,4-dimethylvaleronitrile) (0.7 g) was added as a feed solution dropwise over 1 hour, followed by reaction for 3 hours. About 20 minutes after the start of dropping, heat generation started, and the temperature of the reaction solution rose about 5 ° C. After the reaction for 3 hours, the temperature was raised from 50 ° C. to 80 ° C. and the nitrogen flow rate was increased, and the mixture was stirred for 2 hours to distill off unreacted monomers. After cooling, the black resin particle dispersion obtained by passing through a 200-mesh nylon cloth had a polymerization rate of 92% and a volume average particle size of 0.24 μm. The resulting black resin particle dispersion was also good in dispersion after storage for 1 month.
[0135]
<Preparation of Ink Composition (IJ-4)>
The colored resin particle dispersion was once concentrated by distilling off the solvent and diluted with Isopar G to prepare an ink composition IJ-4 having a viscosity of 13 cp and a surface tension of 23 mN / m. When the ink composition IJ-4 was printed in the same manner as in Example 1 with a color facsimile Saiyuki UX-E1CL (manufactured by Sharp Corporation), high-quality clear printing without bleeding was given. Further, when the scratch resistance was examined in the same manner as in Example 1, it was found that there was no background contamination and it was extremely excellent in scratch resistance. The ink composition had good dispersibility because it did not precipitate and agglomerate even when stored for a long time.
[0136]
Comparative Example 4
<Preparation of Comparative Ink Composition (IJR-1)>
A comparative ink composition (IJR-1) was prepared in the same manner as the ink composition (IJ-4) except that a pigment particle dispersion of seed particles was used instead of the colored resin particles of Example 4. The ink had a viscosity of 12 cp and a surface tension of 23 dyne / cm. The ink composition for comparison (IJR-1) was printed with a color facsimile Saiyuki UX-E1CL (manufactured by Sharp Corporation) in the same manner as in Example 1, giving a print without bleeding, but pointing to the solid image portion. It was found that the image area was easily removed by rubbing with, and the scratch resistance was extremely poor. Further, it has been found that in order to prevent the printed image portion obtained from being rubbed with a finger, it is necessary to heat and fix the print recording body to 120 ° C. or higher.
[0137]
From the experimental results of the ink composition (IJ-4) of the present invention and the comparative ink composition (IJR-1), a dispersion having a polymerizable double bond group using a pigment treated with a polymer as in the present invention as a seed particle Colored resin particles coated with a low-softening resin by seed dispersion polymerization using a stabilizer have clear print image quality, good fixability, very good scratch resistance, good long-term dispersibility, etc. It was found that good ink characteristics were exhibited.
[0138]
Example 5
<Preparation of pigment dispersion>
In Example 1, instead of the black pigment Microlith Blue CT (manufactured by Ciba Specialty Chemicals), yellow pigment Microlithero-3R-T (manufactured by Ciba Specialty Chemicals) was used. Pigment dispersion was performed exactly as in Example 1. The dispersion of the yellow pigment obtained after filtering out the glass beads had a good dispersibility with a volume average particle size of 0.20 μm.
[0139]
<Preparation of colored resin particles>
100 g of a yellow pigment dispersion (solid content 20.0%) was placed in a four-necked flask and heated at a temperature of 80 ° C. for 2 hours with stirring under a nitrogen stream. In Example 1, 4 g of (P-6) as a dispersion stabilizer as a powder, 2 g in a mixed solution of 6.0 g of methyl methacrylate, 12.0 g of methyl acrylate, 2.0 g of dimethylaminoethyl methacrylate and 80 g of Isopar H Except that the solution containing 0.6 g of 2,2'-azobis (2,4-dimethylvaleronitrile) was added as a feed solution and dropped at a drop rate of 2.0 ml / min and reacted for 3 hours, it was exactly the same as Example 1. The reaction operation was performed. The temperature of the reaction solution rose about 4 ° C. The obtained yellow resin dispersion had a polymerization rate of 95%, a volume average particle size of 0.26 μm, and a good dispersion state after storage for 1 month.
[0140]
<Preparation of ink composition (IJ-5)>
The yellow resin particle dispersion was diluted with Isopar G so that the resin particle component was 6.0%. Next, an ink composition (IJ-5) was prepared by adding an octadecene-half-maleic acid octadecylamide copolymer as a charge control agent to 0.01 g / Isopar G 1 liter. Measurement of the charge amount of the ink composition (IJ-5) was carried out using the development characteristics apparatus described in Japanese Examined Patent Publication No. 64-696 (applied voltage 500 V, initial value of time change of voltage induced on the back surface of the applied electrode was measured. ) The ink composition (IJ-5) showed a clear positive charge with an overall charge of 240 mV and a yellow resin particle charge of 201 mV, and was found to be extremely stable with almost no change in the amount of charge after one month. . It was also found that the amount of charge can be easily controlled by the amount of charge control agent.
[0141]
Comparative Example 5
<Preparation of Comparative Ink Composition (IJR-2)>
In Example 5, the yellow pigment dispersion as seed particles was converted into an ink in the same manner as the ink composition (IJ-5) to prepare a comparative ink composition (IJR-2). When the charge amount of the comparative ink composition (IJR-2) was measured, the charge polarity was negative charge, the overall charge was 90 mV, and the charge of the yellow pigment particles was 13 mV.
From Example 5 and Comparative Example 5, the charge polarity of the seed pigment yellow pigment Microlithero-3R-T (comparative ink composition (IJR-2)) was originally negatively charged, but double bonds in the side chain The colored resin particles of the present invention (ink composition (IJ-5)) coated with a resin by seed dispersion polymerization using a group-containing copolymer as a dispersion stabilizer show a positive charge with a clear charge polarity. It can be seen that the amount of charge can also be easily controlled by the amount of charge control agent. That is, it can be seen that the charge amount can be freely controlled by coating the surface of the pigment with resin by seed dispersion polymerization, regardless of the charge polarity of the original pigment.
[0142]
<Image drawability>
A 100 dpi 64-channel electrostatic ink jet head having the head structure shown in FIG. 1 was used as the ink jet device, and the ink composition (IJ-5) was filled in the ink tank. After removing dust on the surface of the coated recording paper as a recording medium by air pump suction, the ejection head was brought close to the coated recording paper to the drawing position, and ink was ejected and drawn at a drawing resolution of 600 dpi. At this time, the drawing was performed while adjusting the pulse voltage and changing the dot area in 16 steps within a dot diameter range of 15 μm to 60 μm. The drawn image gave a clear image of good quality with satisfactory density without blur. The ejection stability from the ink head was also good, there was no clogging, and stable dot-shaped printing was possible even in image drawing. Further, when the scratch resistance was examined in the same manner as in Example 1, it was found that there was no background stain at all and it was extremely excellent in scratch resistance. The ink composition (IJ-5) had good dispersibility because no sedimentation aggregation was observed even when stored for a long period of time.
[0143]
On the other hand, when a comparative ink composition (IJR-2) was used and drawn in the same manner as described above with the negative polarity of the pulse voltage applied to the ejection head, the drawn image was severely blurred and the image density was low. Further, since a discharge failure occurred, a satisfactory image could not be obtained due to missing images.
From the above results, since the pigment resin particles (ink composition (IJ-5)) coated with the resin by seed dispersion polymerization of the present invention have a clear positive charge and a sufficient charge amount, the electrostatic ink jet apparatus It was found that the ink exhibits good ink characteristics such as clear print image quality, good ejection stability, extremely excellent scratch resistance, and good long-term dispersibility.
[0144]
Examples 6-19
<Preparation of pigment dispersion>
In Example 1, 50 wt% of (D-3) is used with respect to the processed pigment instead of the pigment dispersant (D-1), and the blue processed pigment microlith is used instead of the black processed pigment microlith Black CT. Pigment dispersion was performed in the same manner as in Example 1 except that Blue 4G-T (manufactured by Ciba Specialty Chemicals) was used. The pigment dispersion obtained after filtering out the glass beads had a volume average particle size of 0.16 μm and good dispersibility. Using this black pigment dispersion, seed dispersion polymerization was performed to prepare colored resin particles and ink compositions (IJ-6) to (IJ-19).
[0145]
<Colored resin particles>
In Example 1, 157.5 g of a blue processed pigment dispersion (solid content: 19.1%) was used, 8 g of the dispersion stabilizer (P) described in Table-B below was used as a powder, and 40 g of monomer was used. A solution obtained by adding 120 g of Isopar G and 1 mol% of 2,2′-azobis (2,4-dimethylvaleronitrile) to the feed solution was added dropwise to the feed solution in 2 hours. The same reaction procedure was performed. The temperature of the reaction solution increased by about 3 to 8 ° C. The obtained blue particle dispersions 6 to 19 had a polymerization rate of about 89 to 98% and a volume average particle size of 0.20 to 0.26 μm. In addition, the blue particle dispersions 6 to 19 were also excellent in dispersion state after being stored for one month.
[0146]
<Ink composition: IJ-6 to IJ-19>
Ink compositions (IJ-6) to (IJ-19) were prepared by adjusting the viscosity of the colored resin particle dispersions 6 to 19 to 12 to 14 cp and the surface tension to 22 to 24 mN / m, respectively. When the ink compositions (IJ-6) to (IJ-19) were printed with a color facsimile Saiyuki UX-E1CL (manufactured by Sharp Corporation) in the same manner as in Example 1, the ink compositions (IJ-6) to (IJ-6) IJ-19) gave a good quality clear print with satisfactory density without bleeding, and was very excellent in scratch resistance with no visible scum. In addition, the ink compositions (IJ-6) to (IJ-19) had good dispersibility because no sedimentation aggregation was observed even when stored for a long period of time.
[0147]
[Table 2]

[0148]
Example 20
When the ink composition (IJ-5) obtained in Example 5 was subjected to a printing test using an electrophotographic liquid developer using a Ricoh wet copying machine DT-2500, sufficient image density and good fixability were obtained. An image having was obtained. Further, this electrophotographic liquid developer has very little change in charge with time, and has excellent redispersibility and storage stability.
[0149]
【The invention's effect】
The present invention coated with a resin obtained by seed dispersion polymerization using a surface-treated colorant as a seed particle and a copolymer containing a double bond group in a side chain in a non-aqueous solvent as a dispersion stabilizer By using the ink composition containing the colored resin particles, it is possible to obtain an oil-based ink for an ink jet printer in which the colorant is uniformly dispersed in fine particles and the dispersion stability of the colorant dispersion is excellent. Also, it is possible to obtain an oil-based ink for an ink jet printer having high ejection stability without causing clogging at the nozzle portion. Furthermore, an oil-based ink for ink jet printers having excellent drying properties on recording paper, water resistance and light resistance of recorded images, and high scratch resistance can be obtained. In addition, it is possible to obtain an oil-based ink for an electrostatic ink jet printer and a liquid developer for electrophotography that are excellent in dispersion stability and scratch resistance, and also excellent in charge polarity control and charge aging stability. Furthermore, the manufacturing method of the resin particle which has the said characteristic and encloses the coloring agent uniformly disperse | distributed with fine particles can be provided.
[0150]
[Brief description of the drawings]
FIG. 1 is a diagram illustrating a configuration example of a line scanning type multi-channel inkjet head, and is a diagram illustrating a cross section of an ejection electrode corresponding to a recording dot.
FIG. 2 is a diagram of ejection electrodes as viewed from the recording medium side.

Claims (9)

A coloring component obtained by surface-treating a colorant in a non-aqueous solvent having a dielectric constant of 1.5 to 20 and a surface tension of 15 to 60 mN / m (at 25 ° C.) was obtained by dispersing fine particles in the non-aqueous solvent. Using coloring component fine particles as seed particles, at least one monofunctional monomer (M) and a polymerizable double bond group at the terminal of the substituent of the polymer repeating component that is soluble in the non-aqueous solvent Oil-based ink jet printer, characterized by containing colored resin particles obtained by adding at least one dispersion stabilizer (P) containing a polymer as a main component and dispersion polymerization in the presence of a polymerization initiator Ink composition. The dispersion stabilizer (P) is soluble in the non-aqueous solvent and is soluble in the non-aqueous solvent represented by the following general formula (I), and a polymer component A represented by the following general formula (II). The oiliness for an ink jet printer according to claim 1, which is a dispersion stabilizer (P) mainly composed of a polymer component B having a polymerizable double bond group at the terminal of a substituent of the coalescence repeating component. Ink composition.

In the general formula (I), X ⁰ is one selected from —COO—, —OCO—, — (CH ₂ ) _k —OCO—, — (CH ₂ ) _k —COO— and —O—, or a combination thereof. Represents a combined linking group. k represents an integer of 1 to 3.
a ¹ and ^{a 2,} which may be the same or different, each represents a hydrogen atom, a halogen atom, a cyano group, a hydrocarbon group, ^{-COO-Z 1} or ^{-COO-Z 1} (Z 1 via a hydrocarbon hydrogen Represents an atom or a hydrocarbon group which may be substituted.
Q ⁰ represents an aliphatic group having 4 to 22 carbon atoms.

In the general formula (II), X ¹ and X ³ may be the same as or different from each other, and —COO—, —OCO—, — (CH ₂ ) _k COO—, — (CH ₂ ) _k OCO—, — _{O -, - SO 2 -,} - CONHCOO -, - CONHCONH -, - CON (Z 2) -, or _-SO ² N ^(Z 2) - represents a. Here ^{Z 2} represents a hydrocarbon group having 1 to 22 carbon hydrogen atom or a C, k is an integer of 1-4.
W is a group linking the linking group X ² with a binding group X ^1, represents at least one carbon atom, an oxygen atom, a sulfur atom, one made of a silicon atom or a nitrogen atom.
b ¹ and b ² , c ¹ and c ² have the same meanings as a ¹ and a ² in the general formula (I). 2. The oil-based ink composition for an ink jet printer according to claim 1, wherein the colorant is at least one pigment selected from organic pigments and inorganic pigments, and the color component is surface-treated by coating the colorant with a polymer. Stuff. Monofunctional monomer using, as seed particles, colored component fine particles obtained by dispersing a colored component obtained by surface-treating a colorant in a non-aqueous solvent having a volume resistivity of 10 ⁹ Ωcm or more in the form of fine particles in the non-aqueous solvent. At least one of (M) and a dispersion stabilizer (P) comprising a polymer which is soluble in the non-aqueous solvent and has a polymerizable double bond group at the terminal of the substituent of the polymer repeating component as a main component A liquid developer for electrophotography, comprising colored resin particles obtained by adding at least one of the above and dispersing and polymerizing in the presence of a polymerization initiator. The dispersion stabilizer (P) is a polymer component A that is soluble in the non-aqueous solvent represented by the above general formula (I), and the terminal of the substituent of the polymer repeating component represented by the above general formula (II). 5. The electrophotographic liquid developer according to claim 4, which is a dispersion stabilizer mainly comprising a polymer component B having a polymerizable double bond group. 5. The electrophotographic liquid developer according to claim 4, wherein the colorant is at least one pigment selected from organic pigments and inorganic pigments, and the color component is surface-treated by coating the colorant with a polymer. . A coloring component obtained by surface-treating a colorant in a non-aqueous solvent having a dielectric constant of 1.5 to 20 and a surface tension of 15 to 60 mN / m (at 25 ° C.) was obtained by dispersing fine particles in the non-aqueous solvent. Using coloring component fine particles as seed particles, at least one monofunctional monomer (M) and a polymerizable double bond group at the terminal of the substituent of the polymer repeating component that is soluble in the non-aqueous solvent A method for producing colored resin particles, comprising dispersing and polymerizing a dispersion obtained by adding at least one dispersion stabilizer (P) containing a polymer as a main component in the presence of a polymerization initiator. The dispersion stabilizer (P) is a polymer component A that is soluble in the non-aqueous solvent represented by the above general formula (I), and the terminal of the substituent of the polymer repeating component represented by the above general formula (II). The method for producing colored resin particles according to claim 7, which is a dispersion stabilizer mainly comprising a polymer component B having a polymerizable double bond group. 8. The method for producing colored resin particles according to claim 7, wherein the colorant is at least one pigment selected from an organic pigment and an inorganic pigment, and the colorant is coated with a polymer and subjected to a surface treatment.

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