JP3994686B2 - Toner for developing electrostatic image, method for producing the toner, and image forming method using the toner - Google Patents

Description

【０１３８】
【化４】

【０１３９】
また、本発明では結晶性物質として結晶性ポリエステルも用いることができるものであるが、結晶性ポリエステルとしては、脂肪族ジオールと、脂肪族ジカルボン酸（酸無水物および酸塩化物を含む）とを反応させて得られるポリエステルが好ましい。
【０１４０】
結晶性ポリエステルを得るために使用されるジオールとしては、エチレングリコール、ジエチレングリコール、トリエチレングリコール、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、１，４−ブテンジオール、ネオペンチルグリコール、１，５−ペンタングリコール、１，６−ヘキサンジオール、１，４−シクロヘキサンジオール、１，４−シクロヘキサンジメタノール、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グリコール、ビスフェノールＡ、ビスフェノールＺ、水素添加ビスフェノールＡ等を挙げることができる。
【０１４１】
結晶性ポリエステルを得るために使用されるジカルボン酸としては、シュウ酸、マロン酸、コハク酸、グルタル酸、アジピン酸、ピメリン酸、スペリン酸、アゼライン酸、セバシン酸、マレイン酸、フマール酸、シトラコ酸、イタコン酸、グルタコ酸、ｎ−ドデシルコハク酸、ｎ−ドデセニルコハク酸、イソドデシルコハク酸、イソドデセニルコハク酸、ｎ−オクチルコハク酸、ｎ−オクテニルコハク酸、これらの酸無水物あるいは酸塩化物を挙げることができる。
【０１４２】
特に好ましい結晶性ポリエステルとしては、１，４−シクロヘキサンジメタノールとアジピン酸とを反応して得られるポリエステル、１，６−ヘキサンジオールとセバシン酸とを反応して得られるポリエステル、エチレングリコールとコハク酸とを反応して得られるポリエステル、エチレングリコールとセバシン酸とを反応して得られるポリエステル、１，４−ブタンジオールとコハク酸とを反応して得られるポリエステルを挙げることができ、これらのうち、１，４−シクロヘキサンジメタノールとアジピン酸とを反応して得られるポリエステルが最も好ましい。
【０１４３】
上記化合物の添加量は、トナー全体に対し１〜３０質量％、好ましくは２〜２０質量％、更に好ましくは３〜１５質量％である。
【０１４４】
本発明のトナー粒子は、結着樹脂相中に着色剤等が分離相を構成する海島構造を有する粒子が好ましく用いられるが、本発明においては、トナー粒子に占める島部の割合を表す尺度として、トナー粒子の海島構造中における島部の占有状態をボロノイ分割して得られるボロノイ多角形の面積により示す。
【０１４５】
また、本発明に記載の効果である、転写率の向上、ハーフトーンの均一性、微細ドットのチリが無くなるなどの効果が得られるので、本発明に係るトナー粒子は下記に定義されるようなボロノイ多角形（ボロノイ多面体ともいう）の面積の平均値が特定の範囲に入ることが好ましい。ここで、ボロノイ多角形について説明する。
【０１４６】
本発明に係るボロノイ多角形の面積とは、トナー粒子中における島部の占有状況を示す。ボロノイ多角形あるいはボロノイ多面体とは、例えば岩波理化学事典にも掲載されている様に、空間中、あるいは平面上に多数の点が分散しているときに隣り合った点の垂直２等分面、垂直２等分線を作ることにより空間全体を多面体に、または平面全体を多角形に分割させ、この様にして形成される多面体をボロノイ多面体、多角形をボロノイ多角形と呼び、この様な空間や平面の分割をボロノイ分割と呼ぶ。
【０１４７】
図３にボロノイ多角形（ボロノイ多面体）によって分割された本発明に係るトナー粒子の一例を示す。
【０１４８】
すなわち、本発明ではトナー粒子中に存在する島の重心に着目し、隣接し合う島の重心を結んで作られる垂直２等分線によって多角形を形成し、これらの多角形の面積を前記透過型電子顕微鏡より得られた撮影写真に基づき電子顕微鏡装置に設置された画像解析装置により算出する。
【０１４９】
ここで、ボロノイ多角形の面積が大きいものとは、隣接し合う島の重心間の距離が離れたものであることを示すものであり、すなわち、粒子中における島部の占有状態の疎な状態のものを示すものである。また、ボロノイ多角形の面積の小さいものとは、隣接し合う島の重心間の距離が短く近接しているものを示し、すなわち粒子中の島の占有状態が密な状態であることを示す。
【０１５０】
本発明では、トナー粒子中の島部のボロノイ多角形については１０００個のトナーについて測定を行い、ボロノイ多角形の面積の平均値を算出した。
【０１５１】
尚、ボロノイ多角形を数学的に一般定義すると、以下に示される式で定義されるものである。
【０１５２】
《ボロノイ多角形の面積》
２次元空間Ｒ２、または３次元空間Ｒ３におけるＮ個の独立した点Ｐ（ｉ）（１≦ｉ≦Ｎ）についてボロノイ多角形Ｖ（ｉ）の集合は、
Ｖ（ｉ）＝｛Ｘ｜｜Ｘ・Ｐ（ｉ）｜＜｜Ｘ・Ｐ（ｊ）｜
ｆｏｒ ａｌｌ ｉ ｔｏ ｊ｝
式中、Ｘ，Ｐは位置ベクトルで、｜ ｜はユークリッド空間における距離を示す。
【０１５３】
この様に定義されたＶ（ｉ）はＲ２ではボロノイ多角形、Ｒ３ではボロノイ多面体を形成すると仮定し、Ｖ（ｉ）とＶ（ｊ）とが隣合うときにボロノイ多角形の境界は、点Ｐ（ｉ）と点Ｐ（ｊ）を結ぶ線分の垂直２等分線の一部となるものと定義する。ユークリッド空間については、数理科学大辞典等に定義、記載されているとおりのものである。
【０１５４】
また、本発明のトナー粒子の重心、及びトナー粒子中の各島の重心は画像のモーメントによって得られるもので、透過型電子顕微鏡装置に設置された画像解析装置では自動的に算出される。ここで、トナー粒子の重心座標は、トナー粒子の任意の点における微小面積の有する輝度値とその任意の点の座標値との積を求める。そして、トナー粒子全体に存在する全座標について、その輝度と座標値の積を求め、その積の総和をトナー粒子の輝度（前述の様にして得られた各座標点における輝度値の総和）で除することで求められるものである。また、島の重心についても同様、島中の任意の座標点における輝度を求めることによって、島の重心も算出されるものである。この様に、本発明のトナー粒子の重心座標、及びトナー粒子中に存在する各島の重心座標とも各任意の点における輝度に基づき、すなわち画像の明暗から算出されるものである。
【０１５５】
本発明では、トナー粒子中の隣接し合う島の重心間の垂直２等分線により形成されるボロノイ多角形の面積の平均値が２０，０００〜１２０，０００ｎｍ²であり、且つ、その面積の平均値の変動係数が２５％以下のものが好ましい。本発明において、ボロノイ多角形の面積の変動係数は以下の式により算出される。
【０１５６】
ボロノイ多角形の面積の変動係数＝｛Ｓ４／Ｋ４｝×１００（％）
式中、Ｓ４はトナー粒子に存在する島部のボロノイ多角形の面積の標準偏差を示し、Ｋ４はボロノイ多角形の面積の平均値を示す。
【０１５７】
また、本発明に係るトナー粒子中の隣接し合う島のボロノイ多角形の面積の平均値については、より好ましくは４０，０００〜１００，０００ｎｍ²であり、かつその変動係数が２０％以下である。
【０１５８】
本発明に係るトナー粒子中の隣接し合う島の重心間の垂直２等分線により形成されるボロノイ多角形の面積の平均値は２０，０００〜１２０，０００ｎｍ²の範囲内にあるものであるが、この範囲から外れたものは、トナー粒子中における島部の占有状況が好ましくないものとなり、例えば粒子中に島として存在する着色剤がトナー粒子中へ効果的に添加されていないことを示すもので、本発明の効果を見出すことが困難となり好ましくない。
【０１５９】
本発明に係るトナー粒子中の隣接し合う島より形成されるボロノイ多角形の面積の平均値の変動係数とは、ボロノイ多角形の面積のバラツキを特定するもの、すなわちトナー粒子中における島部の占有状態のばらつきを特定するものであり、ボロノイ多角形の面積の平均値の変動係数が２５％以下の範囲が好ましく、更に好ましくは２０％以下である。なお、変動係数が０％のとき、すなわち、ボロノイ多角形の面積の平均値にばらつきのない状態、換言すればトナー粒子中における島の占有状態に全くばらつきのない状態、どのトナー粒子も島の占有状態が同じものである必要性は全くない。
【０１６０】
また、本発明では、トナー粒子の重心から特定範囲内に存在する島により形成されるボロノイ多角形の面積が、その範囲外に存在する島により形成されるボロノイ多角形の面積よりも小さいものであることが好ましい。すなわち、本発明ではトナー粒子の重心から半径１０００ｎｍの外に存在する島によって形成されるボロノイ多角形の面積の平均値が半径１０００ｎｍ以内に存在する島によって形成されるボロノイ多角形の面積の平均値よりも大きいことが好ましく、このことはトナー粒子中においては、島の分散状態がトナー粒子の重心からある程度離れた箇所ではまばらになっていることが好ましいことを意味するものである。この条件を満足することで、本発明に係るトナーではトナー粒子中において島を適度に粒子中に分散させることにより、本発明で達成させた効果が更に効果的に得られるのである。
【０１６１】
また、本発明では、島が適度に分散し、適度に島同士が距離を有し、トナー粒子中において島が偏在しなくなり、着色剤がトナー粒子中に効果的に添加されることから、ボロノイ多角形の面積が１６０，０００ｎｍ²以上となる島がトナー粒子１個中に５〜３０個存在するものが好ましい。
【０１６２】
（樹脂粒子、トナーの分子量分布）
本発明のトナーは、その分子量分布のピークまたは肩が、１００，０００〜１，０００，０００、及び１，０００〜５０，０００に存在することが好ましく、更に分子量分布のピークまたは肩が、１００，０００〜１，０００，０００、２５，０００〜１５０，０００及び１，０００〜５０，０００に存在するものであることが好ましい。
【０１６３】
樹脂粒子の分子量は、１００，０００〜１，０００，０００の領域にピークもしくは肩を有する高分子量成分と、１，０００から５０，０００未満の領域にピークもしくは肩を有する低分子量成分の両成分を少なくとも含有する樹脂が好ましく、更に好ましくは、１５，０００〜１００，０００の部分にピークまたは肩を有する中間分子量体の樹脂を使用することが好ましい。
【０１６４】
前述のトナーあるいは樹脂の分子量測定方法は、ＴＨＦ（テトラヒドロフラン）を溶媒としたＧＰＣ（ゲルパーミエーションクロマトグラフィー）による測定がよい。すなわち、測定試料０．５〜５ｍｇ、より具体的には１ｍｇに対してＴＨＦを１．０ｍｌ加え、室温にてマグネチックスターラーなどを用いて撹拌を行い、充分に溶解させる。次いで、ポアサイズ０．４５〜０．５０μｍのメンブランフィルターで処理した後に、ＧＰＣへ注入する。ＧＰＣの測定条件は、４０℃にてカラムを安定化させ、ＴＨＦを毎分１．０ｍｌの流速で流し、１ｍｇ／ｍｌの濃度の試料を約１００μｌ注入して測定する。カラムは、市販のポリスチレンジェルカラムを組み合わせて使用することが好ましい。例えば、昭和電工社製のＳｈｏｄｅｘ ＧＰＣ ＫＦ−８０１、８０２、８０３、８０４、８０５、８０６、８０７の組合せや、東ソー社製のＴＳＫｇｅｌＧ１０００Ｈ、Ｇ２０００Ｈ、Ｇ３０００Ｈ、Ｇ４０００Ｈ、Ｇ５０００Ｈ、Ｇ６０００Ｈ、Ｇ７０００Ｈ、ＴＳＫ ｇｕａｒｄ ｃｏｌｕｍｎの組合せなどを挙げることができる。又、検出器としては、屈折率検出器（ＩＲ検出器）、あるいはＵＶ検出器を用いるとよい。試料の分子量測定では、試料の有する分子量分布を単分散のポリスチレン標準粒子を用いて作成した検量線を用いて算出する。検量線作成用のポリスチレンとしては１０点程度用いるとよい。
【０１６５】
（現像剤）
本発明のトナーは、一成分現像剤でも二成分現像剤として用いてもよいが、非磁性一成分現像剤として特に好ましく用いられる。
【０１６６】
本発明のトナーは、ａ成分としてフッ素原子を含有する場合、本発明の効果を十分引き出すためＸ線光電子分光法（ＥＳＣＡまたはＸＰＳという）による測定において、６８９．０〜６９２．０ｅＶにピークが存在し、さらに、ピーク強度から計算されるフッ素原子数と炭素原子数との比が０．００１〜０．０．００４であることが好ましい。特に好ましくは、６９０．５〜６９１．０ｅＶにピークが存在し、さらに、ピーク強度から計算されるフッ素原子数と炭素原子数との比が０．００１〜０．００２である。
【０１６７】
また、本発明のトナーは、高い定着性を発揮し、特開平８−３２８２９５号公報に記載されているようなオフセット現象を回避するため、結晶性化合物を含有し、且つ該結晶性化合物に起因する示差熱分析における吸熱ピークが、６０〜１２０℃に１つ以上存在し、その吸熱量が４Ｊ〜３０Ｊ／ｇであることが好ましい。
【０１６８】
次に本発明のトナーの製造方法について説明する。
本発明のトナーは、少なくとも重合性単量体を水系媒体中で重合せしめて得られるものであるが、この製造方法は、重合性単量体を懸濁重合法により重合して樹脂粒子を調製し、あるいは、必要な添加剤の乳化液を加えた液中（水系媒体中）にて単量体を乳化重合、あるいはミニエマルジョン重合を行って微粒の樹脂粒子を調製し、必要に応じて荷電制御性樹脂粒子を添加した後、有機溶媒、塩類などの凝集剤等を添加して当該樹脂粒子を凝集、融着する方法で製造するものである。
【０１６９】
《形状と製造法》
〈乳化重合法〉
また、本発明のトナーを製造する方法として樹脂粒子を水系媒体中で塩析／融着させて調製する方法も挙げることができる。この方法としては、特に限定されるものではないが、例えば、特開平５−２６５２５２号公報や特開平６−３２９９４７号公報、特開平９−１５９０４号公報に示す方法を挙げることができる。すなわち、樹脂粒子と着色剤などの構成材料の分散粒子、あるいは樹脂および着色剤等より構成される微粒子を複数以上塩析、凝集、融着させる方法、特に水中にてこれらを乳化剤を用いて分散した後に、臨界凝集濃度以上の凝集剤を加え塩析させると同時に、形成された重合体自体のガラス転移点温度以上で加熱融着させて融着粒子を形成しつつ徐々に粒径を成長させ、目的の粒径となったところで水を多量に加えて粒径成長を停止し、さらに加熱、攪拌しながら粒子表面を平滑にして形状を制御し、その粒子を含水状態のまま流動状態で加熱乾燥することにより、本発明のトナーを形成することができる。なお、ここにおいて凝集剤と同時にアルコールなど水に対して無限溶解する溶媒を加えてもよい。
【０１７０】
本発明のトナーの製造方法においては、少なくとも重合性単量体に結晶性物質を溶かした後、重合性単量体を重合せしめる工程を経て形成した複合樹脂微粒子と着色剤粒子とを塩析／融着させて得られるものである。本発明のトナーは、重合性単量体に結晶性物質を溶かすものであるが、これは溶解させて溶かすものでも、溶融して溶かすものであってもよい。
【０１７１】
また、本発明のトナーの製造方法は、多段重合法によって得られる複合樹脂微粒子と着色剤粒子とを塩析／融着させるものであるが、多段重合法について以下に説明する。
【０１７２】
《多段重合法により得られる複合樹脂粒子の製造方法》
本発明のトナーの製造方法は、以下に示す工程より構成されるものである。
【０１７３】
１：多段重合工程、
２：複合樹脂粒子と着色剤粒子とを塩析／融着させてトナー粒子を得る塩析／融着工程、
３：トナー粒子の分散系から当該トナー粒子を濾別し、当該トナー粒子から界面活性剤などを除去する濾過・洗浄工程、
４：洗浄処理されたトナー粒子を乾燥する乾燥工程、
５：乾燥処理されたトナー粒子に外添剤を添加する工程
から構成される。
【０１７４】
以下、各工程について、詳細に説明する。
〔多段重合工程〕
多段重合工程とは、オフセット発生防止したトナーを得るべく樹脂粒子の分子量分布を拡大させるために行う重合方法である。すなわち、１つの樹脂粒子において異なる分子量分布を有する相を形成するために重合反応を多段階に分けて行うものであって、得られた樹脂粒子がその粒子の中心より表層に向かって分子量勾配を形成させる様に意図して行うものである。例えば、はじめに高分子量の樹脂粒子分散液を得た後、新たに重合性単量体と連鎖移動剤を加えることによってて低分子量の表層を形成する方法が採られている。
【０１７５】
本発明においては、製造の安定性および得られるトナーの破砕強度の観点から三段重合以上の多段重合法を採用することが好ましい。以下に、多段重合法の代表例である二段重合法および三段重合法について説明する。この様な多段階重合反応によって得られたトナーでは破砕強度の観点から表層程低分子量のものが好ましい。
【０１７６】
〈二段重合法〉
二段重合法は、結晶性物質を含有する高分子量樹脂から形成される中心部（核）と、低分子量樹脂から形成される外層（殻）とにより構成される複合樹脂粒子を製造する方法である。
【０１７７】
この方法を具体的に説明すると、先ず、結晶性物質を単量体に溶解させて単量体溶液を調製し、この単量体溶液を水系媒体（例えば、界面活性剤水溶液）中に油滴分散させた後、この系を重合処理（第一段重合）することにより、結晶性物質を含む高分子量の樹脂粒子の分散液を調製するものである。
【０１７８】
次いで、この樹脂粒子の分散液に、重合開始剤と低分子量樹脂を得るための単量体とを添加し、樹脂粒子の存在下で単量体を重合処理（第二段重合）を行うことにより、樹脂粒子の表面に、低分子量の樹脂（単量体の重合体）からなる被覆層を形成する方法である。
【０１７９】
〈三段重合法〉
三段重合法は、高分子量樹脂から形成される中心部（核）、結晶性物質を含有する中間層及び低分子量樹脂から形成される外層（殻）とにより構成される複合樹脂粒子を製造する方法である。本発明のトナーでは上記の様な複合樹脂粒子として存在するものである。
【０１８０】
この方法を具体的に説明すると、先ず、常法に従った重合処理（第一段重合）により得られた樹脂粒子の分散液を、水系媒体（例えば、界面活性剤の水溶液）に添加するとともに、上記水系媒体中に、結晶性物質を単量体に溶解させてなる単量体溶液を油滴分散させた後、この系を重合処理（第二段重合）することにより、樹脂粒子（核粒子）の表面に、結晶性物質を含有する樹脂（単量体の重合体）からなる被覆層（中間層）を形成して、複合樹脂粒子（高分子量樹脂・中間分子量樹脂）の分散液を調製する。
【０１８１】
次いで、得られた複合樹脂粒子の分散液に、重合開始剤と低分子量樹脂を得るための単量体とを添加し、複合樹脂粒子の存在下で単量体を重合処理（第三段重合）することにより、複合樹脂粒子の表面に、低分子量の樹脂（単量体の重合体）からなる被覆層を形成する。上記方法において、中間層を組み入れることにより、結晶性物質を微細かつ均一に分散することができ好ましい。
【０１８２】
本発明に係るトナーの製造方法においては、重合性単量体を水系媒体中で重合することが１つの特徴である。すなわち、結晶性物質を含有する樹脂粒子（核粒子）または被覆層（中間層）を形成する際に、結晶性物質を単量体に溶解させ、得られる単量体溶液を水系媒体中で油滴分散させ、この系に重合開始剤を添加して重合処理することにより、ラテックス粒子として得る方法である。
【０１８３】
本発明でいう水系媒体とは、水５０〜１００質量％と水溶性の有機溶媒０〜５０質量％とからなる媒体をいう。水溶性の有機溶媒としては、例えば、メタノール、エタノール、イソプロパノール、ブタノール、アセトン、メチルエチルケトン、テトラヒドロフラン等を例示することができ、得られる樹脂を溶解しないアルコール系有機溶媒が好ましい。
【０１８４】
結晶性物質を含有する樹脂粒子または被覆層を形成するために好適な重合法としては、臨界ミセル濃度以下の濃度の界面活性剤を溶解してなる水系媒体中に、結晶性物質を単量体に溶解した単量体溶液を、機械的エネルギーを利用して油滴分散させて分散液を調製し、得られた分散液に水溶性重合開始剤を添加して、油滴内でラジカル重合させる方法（以下、本発明では「ミニエマルジョン法」という。）を挙げることができ、本発明の効果をより発揮することができ好ましい。なお、上記方法において、水溶性重合開始剤に代えて、あるいは水溶性重合開始剤と共に、油溶性重合開始剤を用いても良い。
【０１８５】
機械的に油滴を形成するミニエマルジョン法によれば、通常の乳化重合法とは異なり、油相に溶解させた結晶性物質が脱離が少なく、形成される樹脂粒子または被覆層内に十分な量の結晶性物質を導入することができる。
【０１８６】
ここで、機械的エネルギーによる油滴分散を行うための分散機としては、特に限定されるものではなく、例えば、高速回転するローターを備えた攪拌装置「クレアミックス（ＣＬＥＡＲＭＩＸ）」（エム・テクニック（株）製）、超音波分散機、機械式ホモジナイザー、マントンゴーリンおよび圧力式ホモジナイザーなどを挙げることができる。また、分散粒子径としては、１０ｎｍ〜１０００ｎｍとされ、好ましくは５０ｎｍ〜１０００ｎｍ、更に好ましくは３０ｎｍ〜３００ｎｍである。ここで分散粒子径に分布を持たせることで、トナー粒子中における結晶性物質の相分離構造、すなわちフェレ径、形状係数及びこれらの変動係数を制御してもよい。
【０１８７】
なお、結晶性物質を含有する樹脂粒子または被覆層を形成するための他の重合法として、乳化重合法、懸濁重合法、シード重合法などの公知の方法を採用することもできる。また、これらの重合法は、複合樹脂粒子を構成する樹脂粒子（核粒子）または被覆層であって、結晶性物質を含有しないものを得るためにも採用することができる。
【０１８８】
この重合工程で得られる複合樹脂粒子の粒子径は、電気泳動光散乱光度計「ＥＬＳ−８００」（大塚電子社製）を用いて測定される質量平均粒径で１０ｎｍ〜１０００ｎｍの範囲にあることが好ましい。
【０１８９】
また、複合樹脂粒子のガラス転移温度（Ｔｇ）は４８〜７４℃の範囲にあることが好ましく、更に好ましくは５２〜６４℃である。また、複合樹脂粒子の軟化点は９５〜１４０℃の範囲にあることが好ましい。
【０１９０】
本発明のトナーは、樹脂および着色粒子の表面に、塩析／融着法によって樹脂粒子を融着させてなる樹脂層を形成させて得られるものであるが、このことについて以下に説明する。
【０１９１】
〔塩析／融着工程〕
この塩析／融着工程は、前記多段重合工程によって得られた複合樹脂粒子と着色剤粒子とを塩析／融着させる（塩析と融着とを同時に起こさせる）ことによって、不定形（非球形）のトナー粒子を得る工程である。
【０１９２】
本発明でいう塩析／融着とは、塩析（粒子の凝集）と融着（粒子間の界面消失）とが同時に起こること、または、塩析と融着とを同時に起こさせる行為をいう。塩析と融着とを同時に行わせるためには、複合樹脂粒子を構成する樹脂のガラス転移温度（Ｔｇ）以上の温度条件下において粒子（複合樹脂粒子、着色剤粒子）を凝集させる必要がある。
【０１９３】
この塩析／融着工程では、複合樹脂粒子および着色剤粒子とともに、荷電制御剤などの内添剤粒子（数平均一次粒子径が１０〜１０００ｎｍ程度の微粒子）を塩析／融着させてもよい。また、着色剤粒子は、表面改質されていてもよく、表面改質剤としては、従来公知のものを使用することができる。
【０１９４】
〔熟成工程〕
熟成工程は、塩析／融着工程に後続する工程であり、樹脂粒子の融着後も温度を結晶性物質の融点近傍、好ましくは融点±２０℃に保ち、一定の強度で攪拌を継続することにより、結晶性物質を相分離させる工程である。この工程において結晶性物質のフェレ径、形状係数及びこれらの変動係数を制御することが可能である。
【０１９５】
着色剤粒子は、水性媒体中に分散された状態で塩析／融着処理が施される。着色剤粒子が分散される水性媒体は、臨界ミセル濃度（ＣＭＣ）以上の濃度で界面活性剤が溶解されている水溶液が好ましい。
【０１９６】
着色剤粒子の分散処理に使用する分散機は、特に限定されないが、好ましくは、高速回転するローターを備えた攪拌装置「クレアミックス（ＣＬＥＡＲＭＩＸ）」（エム・テクニック（株）製）、超音波分散機、機械的ホモジナイザー、マントンゴーリン、圧力式ホモジナイザー等の加圧分散機、ゲッツマンミル、ダイヤモンドファインミル等の媒体型分散機が挙げられる。
【０１９７】
複合樹脂粒子と着色剤粒子とを塩析／融着させるためには、複合樹脂粒子および着色剤粒子が分散している分散液中に、臨界凝集濃度以上の塩析剤（凝集剤）を添加するとともに、この分散液を、複合樹脂粒子のガラス転移温度（Ｔｇ）以上に加熱することが必要である。
【０１９８】
塩析／融着させるために好適な温度範囲としては、（Ｔｇ＋１０）〜（Ｔｇ＋５０℃）とされ、特に好ましくは（Ｔｇ＋１５）〜（Ｔｇ＋４０℃）である。また、融着を効果的に行なわせるために、水に無限溶解する有機溶媒を添加してもよい。
【０１９９】
また、本発明においては樹脂粒子と着色剤を水系媒体中において塩析、凝集、融着させて着色粒子（本発明では、トナー粒子と呼ぶ）を得た後、前記トナー粒子を水系媒体から分離するときに、水系媒体中に存在している界面活性剤のクラフト点以上の温度で行うことが好ましく、更に好ましくは、クラフト点〜（クラフト点＋２０℃）の温度範囲で行うことが好ましい。
【０２００】
上記のクラフト点とは、界面活性剤を含有した水溶液が白濁化しはじめる温度であり、クラフト点の測定は下記のように行われる。
【０２０１】
《クラフト点の測定》
塩析、凝集、融着する工程で用いる水系媒体すなわち界面活性剤溶液に、実際に使用する量の凝集剤を加えた溶液を調製し、この溶液を１℃で５日間貯蔵した。次いで、この溶液を攪拌しながら透明になるまで徐々に加熱した。溶液が透明になった温度をクラフト点として定義する。
【０２０２】
トナー粒子への過剰帯電を抑え、均一な帯電性を付与するという観点から、特に環境に対して帯電性を安定化し、維持する為に、本発明の静電荷像現像用トナーは、上記に記載の金属元素（形態として、金属、金属イオン等が挙げられる）をトナー中に２５０〜２００００ｐｐｍ含有することが好ましく、更に好ましくは８００〜５０００ｐｐｍである。
【０２０３】
また、本発明においては、凝集剤に用いる２価（３価）の金属元素と後述する凝集停止剤として加える１価の金属元素の合計値が３５０〜３５０００ｐｐｍであることが好ましい。トナー中の金属イオン残存量の測定は、蛍光Ｘ線分析装置「システム３２７０型」〔理学電気工業（株）製〕を用いて、凝集剤として用いられる金属塩の金属種（例えば、塩化カルシウムに由来するカルシウム等）から発する蛍光Ｘ線強度を測定することによって求めることができる。具体的な測定法としては、凝集剤金属塩の含有割合が既知のトナーを複数用意し、各トナー５ｇをペレット化し、凝集剤金属塩の含有割合（質量ｐｐｍ）と、当該金属塩の金属種からの蛍光Ｘ線強度（ピーク強度）との関係（検量線）を測定する。次いで、凝集剤金属塩の含有割合を測定すべきトナー（試料）を同様にペレット化し、凝集剤金属塩の金属種からの蛍光Ｘ線強度を測定し、含有割合すなわち「トナー中の金属イオン残存量」を求めることができる。
【０２０４】
〔濾過・洗浄工程〕
この濾過・洗浄工程では、上記の工程で得られたトナー粒子の分散系から当該トナー粒子を濾別する濾過処理と、濾別されたトナー粒子（ケーキ状の集合物）から界面活性剤や塩析剤などの付着物を除去する洗浄処理とが施される。ここに、濾過処理方法としては、遠心分離法、ヌッチェ等を使用して行う減圧濾過法、フィルタープレス等を使用して行う濾過法など特に限定されるものではない。
【０２０５】
〔乾燥工程〕
この工程は、洗浄処理されたトナー粒子を乾燥処理する工程である。
【０２０６】
この工程で使用される乾燥機としては、スプレードライヤー、真空凍結乾燥機、減圧乾燥機などを挙げることができ、静置棚乾燥機、移動式棚乾燥機、流動層乾燥機、回転式乾燥機、攪拌式乾燥機などを使用することが好ましい。
【０２０７】
乾燥処理されたトナー粒子の水分は、５質量％以下であることが好ましく、更に好ましくは２質量％以下とされる。なお、乾燥処理されたトナー粒子同士が、弱い粒子間引力で凝集している場合には、当該凝集体を解砕処理してもよい。ここに、解砕処理装置としては、ジェットミル、ヘンシェルミキサー、コーヒーミル、フードプロセッサー等の機械式の解砕装置を使用することができる。
【０２０８】
本発明のトナーは、着色剤の不存在下において複合樹脂粒子を形成し、当該複合樹脂粒子の分散液に着色剤粒子の分散液を加え、当該複合樹脂粒子と着色剤粒子とを塩析／融着させることにより調製されることが好ましい。
【０２０９】
このように、複合樹脂粒子の調製を着色剤の存在しない系で行うことにより、複合樹脂粒子を得るための重合反応が阻害されることない。このため、本発明のトナーによれば、優れた耐オフセット性が損なわれることはなく、トナーの蓄積による定着装置の汚染や画像汚れを発生させることはない。
【０２１０】
また、複合樹脂粒子を得るための重合反応が確実に行われる結果、得られるトナー粒子中に単量体やオリゴマーが残留するようなことはなく、当該トナーを使用する画像形成方法の熱定着工程において、異臭を発生させることはない。
【０２１１】
更に、得られるトナー粒子の表面特性は均質であり、帯電量分布もシャープとなるため、鮮鋭性に優れた画像を長期にわたり形成することができる。このようなトナー粒子間における組成・分子量・表面特性が均質であるトナーによれば、接触加熱方式による定着工程を含む画像形成方法において、画像支持体に対する良好な接着性（高い定着強度）を維持しながら、耐オフセット性および巻き付き防止特性の向上を図ることができ、適度の光沢を有する画像を得ることができる。
【０２１２】
次に、トナー製造工程で用いられる各構成因子について、詳細に説明する。
（重合性単量体）
本発明に用いられる樹脂（バインダー）を造るための重合性単量体としては、疎水性単量体を必須の構成成分とし、必要に応じて架橋性単量体が用いられる。また、下記の様に構造中に酸性極性基を有する単量体または塩基性極性基を有する単量体を少なくとも１種類含有するのが望ましい。
【０２１３】
（１）疎水性単量体
単量体成分を構成する疎水性単量体としては、特に限定されるものではなく従来公知の単量体を用いることができる。また、要求される特性を満たすように、１種または２種以上のものを組み合わせて用いることができる。
【０２１４】
具体的には、モノビニル芳香族系単量体、（メタ）アクリル酸エステル系単量体、ビニルエステル系単量体、ビニルエーテル系単量体、モノオレフィン系単量体、ジオレフィン系単量体、ハロゲン化オレフィン系単量体等を用いることができる。
【０２１５】
ビニル芳香族系単量体としては、例えば、スチレン、ｏ−メチルスチレン、ｍ−メチルスチレン、ｐ−メチルスチレン、ｐ−メトキシスチレン、ｐ−フェニルスチレン、ｐ−クロロスチレン、ｐ−エチルスチレン、ｐ−ｎ−ブチルスチレン、ｐ−ｔｅｒｔ−ブチルスチレン、ｐ−ｎ−ヘキシルスチレン、ｐ−ｎ−オクチルスチレン、ｐ−ｎ−ノニルスチレン、ｐ−ｎ−デシルスチレン、ｐ−ｎ−ドデシルスチレン、２，４−ジメチルスチレン、３，４−ジクロロスチレン等のスチレン系単量体およびその誘導体が挙げられる。
【０２１６】
（メタ）アクリル酸エステル系単量体としては、アクリル酸、メタクリル酸、アクリル酸メチル、アクリル酸エチル、アクリル酸ブチル、アクリル酸−２−エチルヘキシル、アクリル酸シクロヘキシル、アクリル酸フェニル、メタクリル酸メチル、メタクリル酸エチル、メタクリル酸ブチル、メタクリル酸ヘキシル、メタクリル酸−２−エチルヘキシル、β−ヒドロキシアクリル酸エチル、γ−アミノアクリル酸プロピル、メタクリル酸ステアリル、メタクリル酸ジメチルアミノエチル、メタクリル酸ジエチルアミノエチル等が挙げられる。
【０２１７】
ビニルエステル系単量体としては、酢酸ビニル、プロピオン酸ビニル、ベンゾエ酸ビニル等が挙げられ、ビニルエーテル系単量体としては、ビニルメチルエーテル、ビニルエチルエーテル、ビニルイソブチルエーテル、ビニルフェニルエーテル等が挙げられる。
【０２１８】
又、モノオレフィン系単量体としては、エチレン、プロピレン、イソブチレン、１−ブテン、１−ペンテン、４−メチル−１−ペンテン等が挙げられ、ジオレフィン系単量体としては、ブタジエン、イソプレン、クロロプレン等が挙げられる。
【０２１９】
（２）架橋性単量体
樹脂粒子の特性を改良するために架橋性単量体を添加しても良い。架橋性単量体としては、例えば、ジビニルベンゼン、ジビニルナフタレン、ジビニルエーテル、ジエチレングリコールメタクリレート、エチレングリコールジメタクリレート、ポリエチレングリコールジメタクリレート、フタル酸ジアリル等の不飽和結合を２個以上有するものが挙げられる。
【０２２０】
（３）酸性極性基を有する単量体
酸性極性基を有する単量体としては、（ａ）カルボキシル基を有するα，β−エチレン性不飽和化合物、及び、（ｂ）スルホン酸基を有するα，β−エチレン性不飽和化合物を挙げることができる。
【０２２１】
カルボキシル基を有するα，β−エチレン性不飽和化合物の例としては、アクリル酸、メタアクリル酸、フマール酸、マレイン酸、イタコン酸、ケイ皮酸、マレイン酸モノブチルエステル、マレイン酸モノオクチルエステル、およびこれらのＮａ、Ｚｎ等の金属塩類等を挙げることができる。
【０２２２】
スルホン酸基を有するα，β−エチレン性不飽和化合物の例としては、スルホン化スチレン、及びそのＮａ塩、アリルスルホコハク酸、アリルスルホコハク酸オクチル、及びこれらのＮａ塩等を挙げることができる。
【０２２３】
（４）塩基性極性基を有するモノマー
塩基性極性基を有するモノマーとしては、（ｉ）アミン基或いは４級アンモニウム基を有する炭素原子数１〜１２、好ましくは２〜８、特に好ましくは２の脂肪族アルコールの（メタ）アクリル酸エステル、（ii）（メタ）アクリル酸アミドあるいは、随意Ｎ上で炭素原子数１〜１８のアルキル基でモノまたはジ置換された（メタ）アクリル酸アミド、（iii）Ｎを環員として有する複素環基で置換されたビニール化合物及び（iv）Ｎ，Ｎ−ジアリル−アルキルアミン或いはその四級アンモニウム塩を例示することができる。中でも、（ｉ）のアミン基或いは四級アンモニウム基を有する脂肪族アルコールの（メタ）アクリル酸エステルが塩基性極性基を有するモノマーとして好ましい。
【０２２４】
（ｉ）のアミン基或いは四級アンモニウム基を有する脂肪族アルコールの（メタ）アクリル酸エステルの例としては、ジメチルアミノエチルアクリレート、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アクリレート、ジエチルアミノエチルメタクリレート、上記４化合物の四級アンモニウム塩、３−ジメチルアミノフェニルアクリレート、２−ヒドロキシ−３−メタクリルオキシプロピルトリメチルアンモニウム塩等を挙げることができる。
【０２２５】
（ii）の（メタ）アクリル酸アミド或いはモノまたはジアルキル置換された（メタ）アクリル酸アミドとしては、アクリルアミド、Ｎ−ブチルアクリルアミド、Ｎ，Ｎ−ジブチルアクリルアミド、ピペリジルアクリルアミド、メタクリルアミド、Ｎ−ブチルメタクリルアミド、Ｎ，Ｎ−ジメチルアクリルアミド、Ｎ−オクタデシルアクリルアミド等を挙げることができる。
【０２２６】
（iii）のＮを環員として有する複素環基で置換されたビニル化合物としては、ビニルピリジン、ビニルピロリドン、ビニル−Ｎ−メチルピリジニウムクロリド、ビニル−Ｎ−エチルピリジニウムクロリド等を挙げることができる。
【０２２７】
（iv）のＮ，Ｎ−ジアリル−アルキルアミンの例としては、Ｎ，Ｎ−ジアリルメチルアンモニウムクロリド、Ｎ，Ｎ−ジアリルエチルアンモニウムクロリド等を挙げることができる。
【０２２８】
（連鎖移動剤）
分子量を調整することを目的として、公知の連鎖移動剤を用いることができる。連鎖移動剤としては、特に限定されるものではないが、例えば、オクチルメルカプタン、ドデシルメルカプタン、ｔｅｒｔ−ドデシルメルカプタン等のメルカプト基を有する化合物が用いられる。特に、メルカプト基を有する化合物は、加熱定着時の臭気を抑制し、分子量分布がシャープであるトナーが得られ、保存性、定着強度、耐オフセット性に優れることから好ましく用いられる。好ましいものとしては、例えば、チオグリコール酸エチル、チオグリコール酸プロピル、チオグリコール酸プロピル、チオグリコール酸ブチル、チオグリコール酸ｔ−ブチル、チオグリコール酸２−エチルヘキシル、チオグリコール酸オクチル、チオグリコール酸デシル、チオグリコール酸ドデシル、エチレングリコールのメルカプト基を有する化合物、ネオペンチルグリコールのメルカプト基を有する化合物、ペンタエリストールのメルカプト基を有する化合物を挙げることができる。このうち、トナー加熱定着時の臭気を抑制する観点で、ｎ−オクチル−３−メルカプトプロピオン酸エステルが、特に好ましい。
【０２２９】
（界面活性剤）
前述の重合性単量体を使用して、特にミニエマルジョン重合を行うためには、界面活性剤を使用して水系媒体中に油滴分散を行うことが好ましい。この際に使用することのできる界面活性剤としては、特に限定されるものでは無いが、下記のイオン性界面活性剤を好適な化合物の例として挙げることができる。
【０２３０】
イオン性界面活性剤としては、例えば、スルホン酸塩（ドデシルベンゼンスルホン酸ナトリウム、アリールアルキルポリエーテルスルホン酸ナトリウム、３，３−ジスルホンジフェニル尿素−４，４−ジアゾ−ビス−アミノ−８−ナフトール−６−スルホン酸ナトリウム、オルト−カルボキシベンゼン−アゾ−ジメチルアニリン、２，２，５，５−テトラメチル−トリフェニルメタン−４，４−ジアゾ−ビス−β−ナフトール−６−スルホン酸ナトリウム等）、硫酸エステル塩（ドデシル硫酸ナトリウム、テトラデシル硫酸ナトリウム、ペンタデシル硫酸ナトリウム、オクチル硫酸ナトリウム等）、脂肪酸塩（オレイン酸ナトリウム、ラウリン酸ナトリウム、カプリン酸ナトリウム、カプリル酸ナトリウム、カプロン酸ナトリウム、ステアリン酸カリウム、オレイン酸カルシウム等）が挙げられる。
【０２３１】
本発明においては、下記一般式（Ａ）、（Ｂ）で表される界面活性剤が特に好ましく用いられる
一般式（Ａ） Ｒ₁（ＯＲ₂）_nＯＳＯ₃Ｍ
一般式（Ｂ） Ｒ₁（ＯＲ₂）_nＳＯ₃Ｍ
式中、Ｒ₁は炭素数６〜２２のアルキル基またはアリールアルキル基を表すが、好ましくは炭素数８〜２０のアルキル基またはアリールアルキル基であり、更に好ましくは炭素数９〜１６のアルキル基またはアリールアルキル基である。
【０２３２】
Ｒ₁で表される炭素数６〜２２のアルキル基としては、例えば、ｎ−ヘキシル基、ｎ−ヘプチル基、ｎ−オクチル基、ｎ−デシル基、ｎ−ウンデシル基、ｎ−ヘキサデシル基、シクロプロピル基、シクロペンチル基、シクロヘキシル基等が挙げられ、Ｒ１で表されるアリールアルキル基としては、ベンジル基、ジフェニルメチル基、シンナミル基、スチリル基、トリチル基、フェネチル基等が挙げられる。
【０２３３】
一般式（１）、（２）において、Ｒ₂は炭素数２〜６のアルキレン基を表すが、好ましくは炭素数２〜３のアルキレン基である。Ｒ₂で表される炭素数２〜６のアルキレン基としては、エチレン基、トリメチレン基、テトラメチレン基、プロピレン基、エチルエチレン基等が挙げられる。
【０２３４】
一般式（１）、（２）において、ｎは１〜１１の整数であるが、好ましくは２〜１０、更に好ましくは２〜５であり、特に好ましくは２〜３である。また、Ｍで表される１価の金属元素としてはナトリウム、カリウム、リチウム等が挙げられる。中でも、ナトリウムが好ましく用いられる。
【０２３５】
以下に、一般式（１）、（２）で表される界面活性剤の具体例を示すが本発明はこれらに限定されない。
【０２３６】
化合物（１０１）：Ｃ₁₀Ｈ₂₁（ＯＣＨ₂ＣＨ₂）₂ＯＳＯ₃Ｎａ
化合物（１０２）：Ｃ₁₀Ｈ₂₁（ＯＣＨ₂ＣＨ₂）₃ＯＳＯ₃Ｎａ
化合物（１０３）：Ｃ₁₀Ｈ₂₁（ＯＣＨ₂ＣＨ₂）₂ＳＯ₃Ｎａ
化合物（１０４）：Ｃ₁₀Ｈ₂₁（ＯＣＨ₂ＣＨ₂）₃ＳＯ₃Ｎａ
化合物（１０５）：Ｃ₈Ｈ₁₇（ＯＣＨ₂ＣＨ（ＣＨ₃））₂ＯＳＯ₃Ｎａ
化合物（１０６）：Ｃ₁₈Ｈ₃₇（ＯＣＨ₂ＣＨ₂）₂ＯＳＯ₃Ｎａ
本発明においては、トナーの帯電保持機能を良好な状態に保ち、高温高湿下でのカブリ発生を抑え、転写性を向上させる観点から、また、低温低湿下での帯電量上昇を抑え、現像量を安定化させる観点から、上記記載の一般式（１）、（２）で表される界面活性剤の静電荷像現像用トナー中の含有量は、１〜１０００ｐｐｍが好ましく、更に好ましくは５〜５００ｐｐｍであり、特に好ましくは７〜１００ｐｐｍである。
【０２３７】
本発明において、トナーに含有させる界面活性剤の量を上記記載範囲とすることで、本発明の静電荷像現像用トナーの帯電性は、環境の影響に左右されることなく、常に、均一で安定な状態で付与され維持されることが可能である。
【０２３８】
また、本発明の静電荷像現像用トナー中に含有される上記記載の一般式（１）、（２）で表される界面活性剤の含有量は以下に示す方法によって算出される。
【０２３９】
トナー１ｇを５０ｍｌのクロロホルムに溶解させ、１００ｍｌのイオン交換水でクロロホルム層より界面活性剤を抽出する。更に抽出を行ったクロロホルム層を１００ｍｌのイオン交換水でもう一度抽出を行い合計２００ｍｌの抽出液（水層）を得、この抽出液を５００ｍｌまで希釈する。
【０２４０】
この希釈液を試験液として、ＪＩＳ ３３６３６項に規定された方法に従い、メチレンブルーで呈色させ、吸光度を測定し、別途作成した検量線より、トナー中の界面活性剤の含有量を測定するものである。
【０２４１】
また、一般式（１）、（２）で表される界面活性剤の構造は、上記の抽出物を¹Ｈ−ＮＭＲを用いて分析し、構造決定した。
【０２４２】
本発明では、水系媒体中で調製した樹脂粒子の分散液から、樹脂粒子を塩析、凝集、融着する工程において、金属塩を凝集剤として好ましく用いることができるが、２価または３価の金属塩を凝集剤として用いることが更に好ましい。その理由は、１価の金属塩よりも２価、３価の金属塩の方が臨界凝集濃度（凝析値あるいは凝析点）が小さいため好ましい。
【０２４３】
また、本発明では、ノニオン性界面活性剤を使用することもでき、具体的には、ポリエチレンオキサイド、ポリプロピレンオキサイド、ポリプロピレンオキサイドとポリエチレンオキサイドの組合せ、ポリエチレングリコールと高級脂肪酸とのエステル、アルキルフェノールポリエチレンオキサイド、高級脂肪酸とポリエチレングリコールのエステル、高級脂肪酸とポリプロピレンオキサイドのエステル、ソルビタンエステル等が挙げられる。
【０２４４】
本発明では、これらの界面活性剤は、主に乳化重合時の乳化剤として使用されるが他の工程または他の目的で使用してもよい。
【０２４５】
（凝集剤）
本発明では、水系媒体中で調製した樹脂粒子の分散液から、樹脂粒子を塩析、凝集、融着する工程において、金属塩を凝集剤として好ましく用いることができるが、２価または３価の金属塩を凝集剤として用いることが更に好ましい。その理由は、１価の金属塩よりも２価、３価の金属塩の方が臨界凝集濃度（凝析値あるいは凝析点）が小さいため好ましい。
【０２４６】
本発明で用いられる凝集剤は、例えばナトリウム、カリウム、リチウム等のアルカリ金属の塩である１価の金属塩、例えばカルシウム、マグネシウム等のアルカリ土類金属の塩やマンガン、銅等の２価の金属塩、鉄やアルミニウム等の３価の金属塩等が挙げられる。
【０２４７】
これら金属塩の具体的な例を以下に示す。１価の金属塩としては、塩化ナトリウム、塩化カリウム、塩化リチウム、２価の金属塩としては、塩化カルシウム、塩化亜鉛、硫酸銅、硫酸マグネシウム、硫酸マンガン等が挙げられ、３価の金属塩としては、塩化アルミニウム、塩化鉄等が挙げられる。これらは、目的に応じて適宜選択されるが臨界凝集濃度の小さい２価や３価の金属塩が好ましい。
【０２４８】
本発明で云う臨界凝集濃度とは、水性分散液中の分散物の安定性に関する指標であり、凝集剤を添加し、凝集が起こるときの凝集剤の添加濃度を示すものである。この臨界凝集濃度は、ラテックス自身及び分散剤により大きく変化する。例えば、岡村誠三他著 高分子化学１７，６０１（１９６０）等に記述されており、これらの記載に従えば、その値を知ることが出来る。又、別の方法として、目的とする粒子分散液に所望の塩を濃度を変えて添加し、その分散液のζ電位を測定し、ζ電位が変化し出す点の塩濃度を臨界凝集濃度とすることも可能である。
【０２４９】
本発明では、金属塩を用いて臨界凝集濃度以上の濃度になるように重合体微粒子分散液を処理する。この時、当然の事ながら、金属塩を直接加えるか、水溶液として加えるかは、その目的に応じて任意に選択される。水溶液として加える場合には、重合体粒子分散液の容量と金属塩水溶液の総容量に対し、添加した金属塩が重合体粒子の臨界凝集濃度以上になる必要がある。
【０２５０】
本発明では、金属塩の濃度は、臨界凝集濃度以上であれば良いが、好ましくは臨界凝集濃度の１．２倍以上、更に好ましくは１．５倍以上添加される。
【０２５１】
（着色剤）
本発明のトナーは、上記の複合樹脂粒子と着色剤粒子とを塩析／融着して得られるものである。本発明のトナーを構成する着色剤（複合樹脂粒子との塩析／融着に供される着色剤粒子）としては、各種の無機顔料、有機顔料、染料を挙げることができる。無機顔料としては、従来公知のものを用いることができる。具体的な無機顔料を以下に例示する。
【０２５２】
黒色の顔料としては、例えば、ファーネスブラック、チャンネルブラック、アセチレンブラック、サーマルブラック、ランプブラック等のカーボンブラック、更にマグネタイト、フェライト等の磁性粉も用いられる。
【０２５３】
これらの無機顔料は所望に応じて単独または複数を選択併用する事が可能である。また顔料の添加量は重合体に対して２〜２０質量％であり、好ましくは３〜１５質量％が選択される。
【０２５４】
磁性トナーとして使用する際には、前述のマグネタイトを添加することができる。この場合には所定の磁気特性を付与する観点から、トナー中に２０〜６０質量％添加することが好ましい。
【０２５５】
有機顔料及び染料も従来公知のものを用いることができ、具体的な有機顔料及び染料を以下に例示する。
【０２５６】
マゼンタまたはレッド用の顔料としては、例えば、Ｃ．Ｉ．ピグメントレッド２、Ｃ．Ｉ．ピグメントレッド３、Ｃ．Ｉ．ピグメントレッド５、Ｃ．Ｉ．ピグメントレッド６、Ｃ．Ｉ．ピグメントレッド７、Ｃ．Ｉ．ピグメントレッド１５、Ｃ．Ｉ．ピグメントレッド１６、Ｃ．Ｉ．ピグメントレッド４８：１、Ｃ．Ｉ．ピグメントレッド５３：１、Ｃ．Ｉ．ピグメントレッド５７：１、Ｃ．Ｉ．ピグメントレッド１２２、Ｃ．Ｉ．ピグメントレッド１２３、Ｃ．Ｉ．ピグメントレッド１３９、Ｃ．Ｉ．ピグメントレッド１４４、Ｃ．Ｉ．ピグメントレッド１４９、Ｃ．Ｉ．ピグメントレッド１６６、Ｃ．Ｉ．ピグメントレッド１７７、Ｃ．Ｉ．ピグメントレッド１７８、Ｃ．Ｉ．ピグメントレッド２２２等が挙げられる。
【０２５７】
オレンジまたはイエロー用の顔料としては、例えば、Ｃ．Ｉ．ピグメントオレンジ３１、Ｃ．Ｉ．ピグメントオレンジ４３、Ｃ．Ｉ．ピグメントイエロー１２、Ｃ．Ｉ．ピグメントイエロー１３、Ｃ．Ｉ．ピグメントイエロー１４、Ｃ．Ｉ．ピグメントイエロー１５、Ｃ．Ｉ．ピグメントイエロー１７、Ｃ．Ｉ．ピグメントイエロー９３、Ｃ．Ｉ．ピグメントイエロー９４、Ｃ．Ｉ．ピグメントイエロー１３８、Ｃ．Ｉ．ピグメントイエロー１８０、Ｃ．Ｉ．ピグメントイエロー１８５、Ｃ．Ｉ．ピグメントイエロー１５５、Ｃ．Ｉ．ピグメントイエロー１５６等が挙げられる。
【０２５８】
グリーンまたはシアン用の顔料としては、例えば、Ｃ．Ｉ．ピグメントブルー１５、Ｃ．Ｉ．ピグメントブルー１５：２、Ｃ．Ｉ．ピグメントブルー１５：３、Ｃ．Ｉ．ピグメントブルー１６、Ｃ．Ｉ．ピグメントブルー６０、Ｃ．Ｉ．ピグメントグリーン７等が挙げられる。
【０２５９】
また、染料としては、例えば、Ｃ．Ｉ．ソルベントレッド１、同４９、同５２、同５８、同６３、同１１１、同１２２、Ｃ．Ｉ．ソルベントイエロー１９、同４４、同７７、同７９、同８１、同８２、同９３、同９８、同１０３、同１０４、同１１２、同１６２、Ｃ．Ｉ．ソルベントブルー２５、同３６、同６０、同７０、同９３、同９５等を用いることができ、またこれらの混合物も用いることができる。
【０２６０】
これらの有機顔料及び染料は、所望に応じて、単独または複数を選択併用することが可能である。また、顔料の添加量は、重合体に対して２〜２０質量％であり、好ましくは３〜１５質量％である。
【０２６１】
本発明のトナーを構成する着色剤（着色剤粒子）は、表面改質されていてもよい。表面改質剤としては、従来公知のものを使用することができ、具体的にはシランカップリング剤、チタンカップリング剤、アルミニウムカップリング剤等を好ましく用いることができる。シランカップリング剤としては、例えば、メチルトリメトキシシラン、フェニルトリメトキシシラン、メチルフェニルジメトキシシラン、ジフェニルジメトキシシラン等のアルコキシシラン、ヘキサメチルジシロキサン等のシロキサン、γ−クロロプロピルトリメトキシシラン、ビニルトリクロロシラン、ビニルトリメトキシシラン、ビニルトリエトキシシラン、γ−メタクリロキシプロピルトリメトキシシラン、γ−グリシドキシプロピルトリメトキシシラン、γ−メルカプトプロピルトリメトキシシラン、γ−アミノプロピルトリエトキシシラン、γ−ウレイドプロピルトリエトキシシラン等が挙げられる。チタンカップリング剤としては、例えば、味の素社製の「プレンアクト」と称する商品名で市販されているＴＴＳ、９Ｓ、３８Ｓ、４１Ｂ、４６Ｂ、５５、１３８Ｓ、２３８Ｓ等、日本曹達社製の市販品Ａ−１、Ｂ−１、ＴＯＴ、ＴＳＴ、ＴＡＡ、ＴＡＴ、ＴＬＡ、ＴＯＧ、ＴＢＳＴＡ、Ａ−１０、ＴＢＴ、Ｂ−２、Ｂ−４、Ｂ−７、Ｂ−１０、ＴＢＳＴＡ−４００、ＴＴＳ、ＴＯＡ−３０、ＴＳＤＭＡ、ＴＴＡＢ、ＴＴＯＰ等が挙げられる。アルミニウムカップリング剤としては、例えば、味の素社製の「プレンアクトＡＬ−Ｍ」等が挙げられる。
【０２６２】
これらの表面改質剤の添加量は、着色剤に対して０．０１〜２０質量％であることが好ましく、更に好ましくは０．１〜５質量％である。また、着色剤粒子の表面改質法としては、着色剤粒子の分散液中に表面改質剤を添加し、この系を加熱して反応させる方法が挙げられる。この様にして表面改質された着色剤粒子は、濾過により採取され、同一の溶媒による洗浄処理と濾過処理が繰り返された後、乾燥処理されて得られるものである。
【０２６３】
本発明の画像形成方法について説明する。
本発明の画像形成方法は、潜像担持体上に潜像を形成する潜像形成工程と、該潜像をトナーを用いて顕像化する現像工程と、前記潜像担持体上に形成したトナー画像を被転写体上に転写する転写工程と、該トナー画像を加熱部材を用いて該被転写体上に加熱定着する定着工程とを有する画像形成方法において、前記トナーが前記本発明のトナーであり、前記加熱部材が弾性層を有することを特徴とする。本発明の画像形成方法によれば、前記本発明のトナーを用いているため、耐オフセット性及びＯＨＰ透明性に優れ、不快なギラツキのない高画質を得ることができる。
【０２６４】
前記加熱部材における弾性層は、画質を向上させる役割を有し、シリコーンゴムやフッ素系ゴム材料等からなる。前記弾性層の厚みは、目的に応じて適宜選択することができるが、０．５〜５．０ｍｍが好ましい。
【０２６５】
前記加熱部材は、離型層を有することが好ましい。該離型層は、トナーを付着させない目的で、トナーに対して離型性の優れた材料、例えば、フッ素系樹脂等で形成することが好ましい。該フッ素系樹脂の具体例としては、例えば、テトラフルオロエチレンとパーフルオロアルキルビニルエーテルとの共重合体、テトラフルオロエチレンとエチレンとの共重合体、テトラフルオロエチレンとヘキサフルオロエチレンとの共重合体が好ましく挙げられる。前記離型層の厚みは、目的に応じて適宜選択することができるが、１０〜６０μｍが好ましい。
【０２６６】
この際、加熱部材に塗布されるシリコーンオイル等の離型性液体は、塗布しないことが好ましく、塗布しても限りなく少ないことが有効である。該離型性液体は、定着ラチチュードに対しては有効であるが、定着される被転写材に転移するため、ベトツキがあり、また、テープを貼れない、マジックで文字を書き加えられない等の問題がある。これはＯＨＰについて顕著である。また、該離型性液体は、定着表面の荒さをスムーズにできないため、ＯＨＰ透明性の低下の要因にもなっている。前記本発明のトナーの構成では、十分な定着ラチチュードを示すため、定着ロールに塗布されるシリコーンオイル等の離型性液体はわずかでよい。例えば、Ａ４用紙１枚当たりにつき１μｌ以下でよい。この程度の範囲にあれば、前述の諸問題は実質上回避することができる。尚、本発明のトナーの構成では、離型性液体を塗布しなくても十分な定着ラチチュードを示すため、省スペース化を図るために離型性液体塗布機構を取り除くこともできる。
【０２６７】
前記加熱部材が、２本のロールにより構成されている場合、被転写体上のトナー像に接する方のロール表面が、もう一方のロール表面よりも大きく凹んでニップを形成することが、前記被転写体のロールへの巻き付きが発生し難く、好ましい。例えば、被転写体上のトナー像に接する方のロールにおける弾性層の肉厚を２ｍｍ、もう一方のロールにおける弾性層の肉厚を１ｍｍにする、あるいは同じ肉厚で弾性層の硬度を、被転写体上のトナー像に接する方のロールを低く設定し荷重をかけることにより達成することができる。この構成により定着ロール通過直後の被転写体の排出方向が、被転写体上のトナー像に接する方のロールから離れる方向となり、巻き付きが発生し難い。
【０２６８】
前記加熱部材が、１本のロールとベルトとにより構成され、被転写体上のトナー像に接する方がロールであることが、ベルトの熱容量が小さいため消費電力の観点から好ましい。該ベルトの材料は、テトラフルオロエチレン、ポリイミド等の耐熱材料が好ましく、該ベルトの層厚は２ｍｍ以下が好ましく、また、表面には加熱部材と同等なフッ素系樹脂で被覆することが好ましい。また、ベルトを介し、ベルト内部から加圧ロール等で被転写体上のトナー像に接するロールへ圧力を与えて凹みを形成させることにより、定着ロール通過直後の被転写体の排出方向が、被転写体上のトナー像に接する方のロールから離れる方向となり、巻き付きが発生し難く好ましい。
【０２６９】
前記加熱部材の表面温度が、前記本発明のトナーに含まれるワックスのＤＳＣ吸熱ピークにおける温度よりも３０℃以上高いことが好ましく、５０℃以上高いことがより好ましい。該表面温度が、該ワックスのＤＳＣ吸熱ピーク温度よりも３０℃以上高くないと、該ワックスの離型効果を十分に発揮できなくなることがある。
【０２７０】
前記加熱部材の温度コントロールセンサとして熱電対等の接触型のタイプを使用する場合、従来の離型性液体を多く塗布するタイプと異なり、本発明の構成では加熱部材の表面が摩耗しやすいため、前記温度コントロールセンサの位置が画像部に存在すると画質欠陥となるため、非画像部に設定することが好ましい。この非画像部とは、用紙の通過しない部分とともに用紙上にトナーが転写されない端部も含む。
【０２７１】
以下、本発明の画像形成方法に用いられる画像形成装置につき図４を用いて説明する。なお、本発明の画像形成方法に用いられる画像形成装置は図４に示されるものに限定されるものではない。
【０２７２】
図４（ａ）は実施の形態の現像器付近の構成を示す概略断面図、（ｂ）はその要部断面図である。図示のように、現像装置３（現像器３ともいう）は、現像スリーブ（現像剤担持体）１４０が感光体ドラム（静電潜像担持体）１と対向するようにして、感光体ドラム１の周面に近接した位置に設けられている。また、現像スリーブ１４０と感光体ドラム１との間には位置決め部材（０．１ｍｍ厚のポリエステルフィルム）１６０が介挿されており、これにより、現像スリーブ１４０と感光体ドラム１とのギャップ（空隙）距離Ｄｓを所定値に設定している。
【０２７３】
現像器３のホッパ１２０内には、本発明に用いられる非磁性一成分トナーが収納されており、スクリューや攪拌羽根等により現像装置３内を搬送されて、現像スリーブ１４０に至る。現像スリーブ１４０に至ったトナーは、規制部材（例：０．１ｍｍ厚のＳＵＳ（ステンレススチール）板）１５０との摩擦により所定の極性に帯電されて現像スリーブ１４０の周面に薄層状に担持される。この薄層の厚みは規制部材１５０の素材や押圧力等で定まるが、本例では、感光体ドラム１の周速度を１００ｍｍ／ｓｅｃ、現像スリーブ１４０の周速度を２００ｍｍ／ｓｅｃ、規制部材１５０が現像スリーブ１４０を押圧する押圧力を１０〜１００Ｎ／ｍとすることにより、１．５層程度（トナー粒子１．５個分程度の厚み）としている。なお、規制部材１５０との摩擦帯電によりトナーが所定の極性に帯電されて現像スリーブ１４０の周面上に薄層状に担持されるプロセスは、例えば、特公昭６３−１５５８０号公報に記載されているように公知であるため説明は省略する。
【０２７４】
現像スリーブ１４０は導電性を有するフレキシブルな素材（例：肉厚１ｍｍのポリアミド樹脂）を用いて円筒状（例：直径１７ｍｍ）に構成されている。現像スリーブ１４０の内部には径が僅かに現像スリーブ１４０よりも小さい（例：直径１６ｍｍ）駆動ローラ１３０が収納されており、該駆動ローラ１３０が矢印方向へ回転すると、該駆動ローラ１３０の外周面と現像スリーブ１４０の内周面との摩擦力で現像スリーブ１４０が駆動されて同方向へ回転するように構成されている。また、上述のように、現像スリーブ１４０はフレキシブルであり、且つ、駆動ローラ１３０よりも僅かに径が大きいため、若干の弛みが存在する。この弛みは、規制部材１５０と不図示のガイドベルトとによって、感光体ドラム１と対向している側に於いて発生するように規制されている。このため、現像スリーブ１４０からの押圧力の一部は上記弛みで吸収され、その結果、現像スリーブ１４０と感光体ドラム１との間に介挿されている位置決め部材１６０に対して現像スリーブ１４０から加わる押圧力は、比較的低圧となる。
【０２７５】
現像スリーブ１４０の周面上に薄層状に担持されたトナーは、現像スリーブ１４０の回転に伴い搬送されて、現像領域Ｄａに至る。現像領域Ｄａとは、現像スリーブ１４０の周面上のトナーが、現像バイアス電源装置から印加される現像バイアス電圧Ｖｂと交番電圧とにより形成される電界の作用で、現像スリーブ１４０の周面から飛翔されてパウダクラウド化され、感光体ドラム１の周面上の静電潜像を現像する領域である。この領域は、現像スリーブ１４０と感光体ドラム１のニップ幅Ｄａ内の領域でもある。現像バイアス電源装置は、現像バイアス電圧Ｖｂの設定値（例：−５００Ｖ程度）を出力する直流電圧電源と、交番電界（例：Ｖｐｐ２．０ｋＶ，周波数２ｋＨｚ）を形成するための交流電源装置とから構成されている。
【０２７６】
交番電界により現像スリーブから飛翔されたトナーがパウダクラウド化されて感光体上の静電潜像を現像するプロセスについては、例えば、電子写真技術の基礎と応用（電子写真学会編・コロナ社）の１５８頁〜１７０頁に記載されているように公知であるため、説明は省略する。なお、Ｖｐｐとは交番電圧波形の振幅の山と谷の差であるピーク・トゥー・ピーク電圧を意味する。
【０２７７】
感光体ドラム１は、本例では、負帯電性の有機感光体で構成される表面を有し、図内矢印方向へ定速回転される光導電性のドラムである。この感光体ドラム１は、不図示の帯電装置により一様な電位（例：−８００Ｖ程度）に帯電された後、レーザ等の光学ヘッドにより露光されて電位を減衰される（例：−１００Ｖ程度）。つまり、静電潜像が形成される。この静電潜像が上記現像領域Ｄａに至ると、上記の電位減衰部分に、前述のようにパウダクラウド化されたトナーが付着して、現像が行われる。
【０２７８】
位置決め部材１６０は、その先端縁部（図では下端部）１６ａが前記現像領域Ｄａ内に位置し、且つ、該現像領域Ｄａの長手方向と平行になるように、現像スリーブ１４０と感光体ドラム１との間の回転方向上流側の位置（図では上半部側の位置）に介挿されており、現像スリーブ１４０と感光体ドラム１から圧接されている。これにより、現像スリーブ１４と感光体ドラム１のギャップ距離Ｄｓが所定値に設定されるとともに、先端縁部１６ａが長手方向に沿って設けられているため画像幅の全域に渡ってギャップ距離Ｄｓが適正値に設定されている。位置決め部材１６０は、本例では前述のように０．１ｍｍ厚のポリエステルフィルムが用いられているが、ポリエステルフィルムに限定されない。トナーの摩擦帯電との兼ね合いを考慮して素材を選択してもよく、例えば、トナーの帯電極性と逆極性の帯電系列材料を用いることにより、規制部材１５０による摩擦帯電を補助もしくは助長するように構成してもよい。また、２層構造として、現像スリーブ１４０と接触する面を導電性の素材で構成してトナーの帯電極性と同極性の電圧を印加することにより、トナーの付着を防止するとともにトナーの帯電を補助するようにしてもよい。
【０２７９】
また、位置決め部材１６０は、本例では、図示のように現像スリーブ１４０と感光体ドラム１の回転の上流側に設けられていて現像領域Ｄａ中の上流側の部分を遮蔽しているが、下流側に設けて現像領域Ｄａ中の下流側の部分を遮蔽してもよい。本例のように上流側に設けた場合には、位置決め部材１６０が回転方向に沿うように設けられるため、現像スリーブ１４０や感光体ドラム１から受ける抵抗が少なくなり、トナーの飛翔に不具合を生じ難いという効果がある。また、現像スリーブ１４０と感光体ドラム１の少なくとも一方がフレキシブルもしくは弾性を有する場合でも、ギャップ距離Ｄｓを適正値に設定できる効果がある。
【０２８０】
次に、位置決め部材１６０の先端縁部１６ａの位置と、現像スリーブ１４０と感光体ドラム１間のギャップ距離Ｄｓと、トナー付着量の関係を説明する。現像スリーブ１４０の表面からのトナーの飛翔とパウダクラウド化は、主に、ギャップ距離Ｄｓと、現像領域の回転方向の幅Ｄａと、現像バイアス電圧Ｖｂとによって定まる。また、交番電界を形成する場合であれば、印加電圧波形の振幅差電圧Ｖｐ−ｐも寄与する。飛翔方式の現像装置を構成する場合、電源側の精度を向上させることは比較的容易であるが、ギャップ距離Ｄｓを安定して確保することは困難である。このため、本例では、位置決め部材１６０を用いている。
【０２８１】
ギャップ距離Ｄｓは上述のように位置決め部材１６０によって容易に適正値に設定できるのであるが、この位置決め部材１６０の存在によって現像領域の一部（図示の例では上側の部分）が遮蔽されてしまう。このため、感光体ドラム１上でのトナー付着量が低下して現像濃度の低下という不具合を生ずる。十分な印字画像濃度を得るためには０．７ｍｇ／ｃｍ²以上のトナー付着量があればよく、１．５ｍｍ以上の現像ニップ幅Ｄａを確保することで、十分なトナー付着量を得ることができる。
【０２８２】
このため、位置決め部材１６０の先端縁部１６ａの位置を、現像ニップ幅Ｄａが１．５ｍｍ以上となる範囲内に設定する必要がある。
【０２８３】
上述の例を種々に変形することが可能である。例えば、交番電界を形成するための振幅電圧差Ｖｐｐとして１００〜３０００Ｖ程度、その周波数として１００〜１０ｋＨｚ程度、波形として三角波、矩形波を用いることもできる。また、位置決め部材１６０の厚みとして０．０１〜０．５ｍｍ程度を用い、上述の交番電界と組み合わせて用いることもできる。非磁性のトナーに代えて磁性トナーを用いることもできる。また、フレキシブル現像スリーブに代えて現像ローラを用いるとともに、感光体を弾性を有するように構成することもできる。また、位置決め部材１６０を非画像印字領域中に脱着することで、現像同時清掃装置として使用することもできる。
【０２８４】
図５は、カラー電子写真画像形成装置の一例を示す概略構成図である。
カラー電子写真画像形成装置の本体内には第１、第２、第３及び第４画像形成部Ｐａ、Ｐｂ、Ｐｃ及びＰｄが並列設置される。各画像形成部は同様の構成とされ、各々異なった色の可視像（トナー像）を形成する。
【０２８５】
画像形成部Ｐａ、Ｐｂ、Ｐｃ及びＰｄは、それぞれ専用の静電潜像担持体（電子写真感光体ドラム）１ａ、１ｂ、１ｃ及び１ｄを具備する。各画像形成部Ｐａ、Ｐｂ、Ｐｃ及びＰｄにて形成された電子写真感光体ドラム（感光体ドラムと略すことがある）１ａ、１ｂ、１ｃ及び１ｄ上の画像は、各画像形成部に隣接して移動する記録材担持体１８上に担持し搬送される記録材（転写材、画像支持体）上に転写される。更に、記録材上の画像は、定着部（定着器）１０にて加熱及び加圧して定着され、記録材はトレイ６１へと排出される。
【０２８６】
次に、各画像形成部における潜像形成部について説明する。感光体ドラム１ａ、１ｂ、１ｃ、１ｄの外周には、各々除電露光ランプ２１ａ、２１ｂ、２１ｃ、２１ｄ、ドラム帯電器２ａ、２ｂ、２ｃ、２ｄ、像露光手段としてのレーザビーム露光装置１７、電位センサ２２ａ、２２ｂ、２２ｃ、２２ｄが設けられている。除電露光ランプ２１ａ、２１ｂ、２１ｃ、２１ｄにより除電された感光体ドラム１ａ、１ｂ、１ｃ、１ｄは、ドラム帯電器２ａ、２ｂ、２ｃ、２ｄにより一様に帯電され、次いで、レーザビーム露光装置１７により露光されることにより、感光体ドラム１ａ、１ｂ、１ｃ、１ｄの上には、画像信号に応じた色分解された静電潜像が形成される。本発明の画像形成装置は、像露光手段としては、上述のレーザビーム露光装置１７の他に、ＬＥＤアレー露光装置などのように、基本画像単位（画素）においてオフ以外の光量レベルが複数の光を照射可能な、周知の多値露光手段を好適に採用し得る。
【０２８７】
前記感光体ドラム上の静電潜像は、現像手段にて現像され可視像とされる。つまり、現像手段は、それぞれシアン色、マゼンタ色、イエロー色、ブラック色の現像剤を所定量充填された現像器３ａ、３ｂ、３ｃ、３ｄを備えており、上記感光体ドラム１ａ、１ｂ、１ｃ、１ｄに形成された静電潜像を現像し、可視画像（トナー像）とする。
【０２８８】
次に、転写部について説明する。記録材カセット６０中に保持された記録材は、レジストローラーを経て記録材担持体１８へと送給される。
【０２８９】
この記録材担持体１８が回転し始めると、記録材がレジストローラーから記録材担持体１８上へと搬送される。このとき画像書き出し信号がＯＮとなり、適正なタイミングにより第１の電子写真感光体ドラム１ａ上に画像形成を行う。
【０２９０】
第１の電子写真感光体ドラム１ａの下方には、転写帯電器４ａ及び転写押圧部材４１ａが設けていて、転写押圧部材４１ａにて感光体ドラムの方へと均一な押力を付与し、且つ、転写帯電器４ａが電界を付与することにより感光体ドラム１ａ上のトナー像を記録材上へと転写させる。このとき、記録材は、記録材担持体１８上に静電吸着力で保持され、第２の画像形成部Ｐｂへと記録材は搬送され、次の転写が行なわれる。以下、上記と同様な方法により第３、第４の画像形成部Ｐｃ、Ｐｄによって形成されたトナー像が転写された記録材は、分離帯電器（分離極）９によって除電され、静電吸着力の減衰によって記録材担持体１８から離脱し、定着部（定着器）１０へと搬送される。
【０２９１】
定着部１０は、定着ローラ７１、加圧ローラ７２、ローラ７１、７２をそれぞれクリーニングする耐熱性クリーニング部材７３、７４、各ローラ７１、７２を加熱するヒータ７５、７６、ジメチルシリコーンなどの離型剤オイルを定着ローラ７１に塗布するオイル塗布ローラ７７、そのオイルを供給するためのオイル溜め７８、定着温度制御用のサーミスタ７９から構成されている。
【０２９２】
転写後、感光体ドラムｌａ、ｌｂ、ｌｃ、ｌｄ上に残留したトナー等は、感光体クリーニング部５ａ、５ｂ、５ｃ、５ｄにより除去され、引き続き行われる次の潜像形成に備えられる。又、画像支持体８上に残留したトナー等は、ベルト除電器１２によって除電され静電吸着力を取り除かれた後、本例では不織布を備えたクリーニング装置６２にて除去される。クリーニング装置６２としては回転するファーブラシとか、ブレードとか、これらを併用した装置等も用いられる。
【０２９３】
また、本発明に使用される好適な定着方法としては、いわゆる接触加熱方式を図７、図８を用いて説明する。
【０２９４】
図７、図８は、各々、本発明に用いられる定着器の一態様を示す概略断面図である。
【０２９５】
本発明においては、特に、接触加熱方式として、熱圧定着方式、さらには熱ロール定着方式および固定配置された加熱体を内包した回動する加圧部材により定着する圧接加熱定着方式をあげることができる。
【０２９６】
図７、図８で示される熱ロール定着方式では、多くの場合表面にテトラフルオロエチレンやポリテトラフルオロエチレン−パーフルオロアルコキシビニルエーテル共重合体類等を被覆した鉄やアルミニウム等で構成される金属シリンダー内部に熱源を有する上ローラーとシリコーンゴム等で形成された下ローラーとから形成されている。熱源としては、線状のヒータを有し、上ローラーの表面温度を１２０〜２００℃程度に加熱するものが代表例である。定着部に於いては上ローラーと下ローラー間に圧力を加え、下ローラーを変形させ、いわゆるニップを形成する。ニップ幅としては１〜１０ｍｍ、好ましくは１．５〜７ｍｍである。定着線速は４０ｍｍ／ｓｅｃ〜６００ｍｍ／ｓｅｃが好ましい。
【０２９７】
定着クリーニングの機構を付与して使用してもよい。この方式としてはシリコーンオイルを定着の上ローラーあるいはフィルムに供給する方式やシリコーンオイルを含浸したパッド、ローラー、ウェッブ等でクリーニングする方法が使用できる。
【０２９８】
次に、本発明で用いられる固定配置された加熱体を内包した回動する加圧部材により定着する方式について説明する。
【０２９９】
この定着方式は、固定配置された加熱体と、該加熱体に対向圧接し、且つフィルムを介して転写材を加熱体に密着させる加圧部材とにより圧接加熱定着する方式である。
【０３００】
この圧接加熱定着器は、加熱体が従来の加熱ローラーに比べて熱容量が小さく、転写材の通過方向と直角方向にライン状の加熱部を有するものであり、通常加熱部の最高温度は１００〜３００℃である。
【０３０１】
なお、圧接加熱定着とは、通常よく用いられるごとく加熱部材と加圧部材の間を、未定着トナーをした転写材を通す方式等、加熱源に未定着トナー像を押し当てて定着する方法である。こうすることにより加熱が迅速に行われるため、定着の高速化が可能となるが、温度制御が難しく、加熱源表面部分等の未定着トナーを直接圧接される部分に、トナーが付着残留したいわゆるトナーオフセットが起こりやすく、また転写材が定着器に巻き付きを起こす等の故障も起こしやすいという問題点もある。
【０３０２】
この定着方式では、装置に固定支持された低熱容量のライン状加熱体は、厚さにして０．２〜５．０ｍｍ、さらに好ましくは０．５〜３．５ｍｍで幅１０〜１５ｍｍ、長手長２４０〜４００ｍｍのアルミナ基板に抵抗材料を１．０〜２．５ｍｍに塗布したもので両端より通電される。
【０３０３】
通電はＤＣ１００Ｖの周期１５〜２５ｍｓｅｃのパルス波形で、温度センサにより制御された温度・エネルギー放出量に応じたパルス幅に変化させてあたえる。低熱容量ライン状加熱体において、温度センサで検出された温度Ｔ１の場合、抵抗材料に対向するフィルムの表面温度Ｔ２はＴ１よりも低い温度となる。ここでＴ１は１２０〜２２０℃が好ましく、Ｔ２の温度はＴ１の温度と比較して０．５〜１０℃低いことが好ましい。また、フィルムがトナー表面より剥離する部分におけるフィルム材表面温度Ｔ３はＴ２とほぼ同等である。フィルムは、この様にエネルギー制御・温度制御された加熱体に当接して図９（ａ）の中央矢印方向に移動する。これら定着用フィルムとして用いられるものは、厚みが１０〜３５μｍの耐熱フィルム、例えばポリエステル、ポリパーフルオロアルコキシビニルエーテル、ポリイミド、ポリエーテルイミドに、多くの場合はテフロン（Ｒ）等のフッ素樹脂に導電材を添加し離型剤層を、５〜１５μｍ被覆させたエンドレスフィルムである。
【０３０４】
フィルムの駆動には、駆動ローラーと従動ローラーにより駆動力とテンションをかけられて矢印方向へシワ・ヨレがなく搬送される。定着器としての線速は４０〜６００ｍｍ／ｓｅｃが好ましい。
【０３０５】
加圧ローラーはシリコーンゴム等の離型性の高いゴム弾性層を有し、フィルム材を介して加熱体に圧着され、圧接回転する。
【０３０６】
また、上記にはエンドレスフィルムを用いた例を説明したが、図９（ｂ）の様にフィルムシートの送り出し軸と巻き取り軸を使用し、有端のフィルム材を使用してもよい。さらには内部に駆動ローラー等を有しない単なる円筒状のものでもよい。
【０３０７】
上記定着器にはクリーニング機構を付与して使用してもよい。クリーニング方式としては、各種シリコーンオイルを定着用フィルムに供給する方式や各種シリコーンオイルを含浸させたパッド、ローラー、ウェッブ等でクリーニングする方式が用いられる。
【０３０８】
なお、シリコーンオイルとしては、ポリジメチルシロキサン、ポリメチルフェニルシロキサン、ポリジフェニルシロキサン等を使用することが出来る。さらに、フッ素を含有するシロキサンも好適に使用することが出来る。
【０３０９】
次に図９にこの定着器の構成断面図の例を示す。
図９（ａ）において、８４は装置に固定支持された低熱容量ライン状加熱体であって、一例として高さが１．０ｍｍ、幅が１０ｍｍ、長手長が２４０ｍｍのアルミナ基板８５に抵抗材料８６を幅１．０ｍｍに塗工したものであり、長手方向両端部より通電される。
【０３１０】
通電は例えばＤＣ１００Ｖで通常は周期２０ｍｓｅｃのパルス状波形でなされ、検温素子８７からの信号によりコントロールされ所定温度に保たれる。このためエネルギー放出量に応じてパルス幅を変化させるが、その範囲は例えば０．５〜５ｍｓｅｃである。
【０３１１】
このように制御された加熱体８４に移動するフィルム８８を介して未定着トナー像９３を担持した転写材９４を当接させてトナーを熱定着する。
【０３１２】
ここで用いられるフィルム８８は、駆動ローラー８９と従動ローラー９０によりテンションをかけられた状態でシワの発生なく移動する。９５はシリコーンゴム等で形成されたゴム弾性層を有する加圧ローラーであり、総圧０．４〜２．０Ｎでフィルムを介して加熱体を加圧している。転写材９４上の未定着トナー像９３は、入口ガイド９６により定着部に導かれ、加熱により定着像を得る。
【０３１３】
以上はエンドレスベルトで説明したが、図９（ｂ）のごとく、フィルムシート繰り出し軸９１および巻き取り軸９２を使用し、定着用のフィルムは有端のものでもよい。
【０３１４】
【実施例】
以下、実施例を挙げて本発明を詳細に説明するが、本発明の態様はこれに限定されない。なお、文中「部」とは「質量部」を表す。
【０３１５】
実施例１
《樹脂粒子の製造例》
（樹脂粒子Ｓ１の製造）
温度計、還流冷却器、撹拌機およびモノマーチャージ器を備えたセパラブルフラスコに脱イオン水を４３０部を入れて、窒素ガスで酸素を置換した後７０℃に昇温し、過硫酸カリウム（ＫＰＳ）５部を入れ撹拌を行った。
【０３１６】
上記と同一の装置を備えたセパラブルフラスコを用意し、ビニル重合性単量体として、メチルメタクリレート（ＭＭＡ）４４部、ｎ−ブチルアクリレート４４部、重合性単量体Ａとして、化合物（１−１）（２，２，２−トリフロオロエチルメタクリレート）を１００部、酸性極性基を有する重合性単量体Ｂとして、メタクリル酸１２部、連鎖移動剤して、ｎ−オクチル−３−メルカプトプロピオン酸エステル１部を脱イオン水４８０部、アニオン系界面活性剤（ドデシルベンゼンスルフォン酸ナトリウム：ＳＤＳ）９部で乳化したもの５％をシードとして、過硫酸カリウムの入ったセパラブルフラスコに加え２０分間重合した。
【０３１７】
更に、残りの乳化物を５時間にわたって連続的にフラスコ中に滴下した。それから更に、７５℃で３時間反応させた後、５０℃に冷却し、イオン交換水で５倍に希釈したのちアンモニア水でｐＨ８に調整し、樹脂粒子Ｓ１を得た。
【０３１８】
（樹脂粒子Ｓ２〜Ｓ５、およびＳ８の製造）
樹脂粒子Ｓ１の製造において、重合性単量体Ａ、重合性単量体Ｂ、ビニル重合性単量体を表１に記載のように変更した以外は、同様にして樹脂粒子Ｓ２〜Ｓ５、およびＳ８を各々、製造した。
【０３１９】
（樹脂粒子Ｓ６の製造）
温度計、還流冷却器、攪拌機およびモノマーチャージ器を備えたセパラブルフラスコに脱イオン水９９８部を入れて、窒素ガスで酸素を置換した後７２℃に昇温し、過硫酸カリウム５部を入れ攪拌を行った。
【０３２０】
上記と同一の装置を備えたセパラブルフラスコを用意し、ビニル重合性単量体として、メチルメタクリレート（ＭＭＡ）４４部、ｎ−ブチルアクリレート４４部、重合性単量体Ａとして、化合物（１−１）２，２，２−トリフロオロエチルメタクリレート１００部、重合性単量体Ｂとして、メタクリル酸１２部、連鎖移動剤としてｎ−オクチル−３−メルカプトプロピオン酸エステル１部を脱イオン水１９１部、ＳＤＳ２．２部で乳化したものの５％をシードとして、過硫酸カリウムの入ったセパラブルフラスコに加え２０分間重合した。更に残りの乳化物を１．５〜２時間にわたって連続的にフラスコ中に滴下し、コア部とした。
【０３２１】
その後１時間反応させ、コア部と同様に、ビニル重合性単量体として、メチルメタクリレート（ＭＭＡ）４４部、ｎ−ブチルアクリレート４４部、重合性単量体Ｂとして、メタクリル酸１２部、連鎖移動剤してｎ−オクチル−３−メルカプトプロピオン酸エステル１部で乳化したものを１〜２時間にわたって上記の３リットルセパラブルフラスコ中に連続的に滴下し、シェル部とした。
【０３２２】
それから更に７５℃で２時間反応させた後、５０℃に冷却しアンモニア水でｐＨ８に調整し、コアシェル構造を有する樹脂粒子Ｓ６を得た。
【０３２３】
（樹脂粒子Ｓ７の製造）
温度計、還流冷却器、攪拌機およびモノマーチャージ器を備えたセパラブルフラスコに脱イオン水９９８部を入れて、窒素ガスで酸素を置換した後７２℃に昇温し、過硫酸カリウム５部を入れ攪拌を行った。
【０３２４】
上記と同一の装置を備えたセパラブルフラスコを用意し、ビニル重合性単量体として、メチルメタクリレート（ＭＭＡ）４４部、ｎ−ブチルアクリレート４４部、重合性単量体Ｂとして、メタクリル酸１２部、連鎖移動剤してｎ−オクチル−３−メルカプトプロピオン酸エステル１部を脱イオン水１９１部、ＳＤＳ２．２部で乳化したものの５％をシードとして、上記過硫酸カリウムの入ったセパラブルフラスコに加え２０分間重合した。更に残りの乳化物を１．５〜２時間にわたって連続的にフラスコ中に滴下し、コア部とした。
【０３２５】
その後１時間反応させ、コア部と同様に、ビニル重合性単量体として、メチルメタクリレート（ＭＭＡ）４４部、ｎ−ブチルアクリレート４４部、重合性単量体Ａとして、化合物（１−１）（２，２，２−トリフロオロエチルメタクリレート）１００部、重合性単量体Ｂとして、メタクリル酸１２部、連鎖移動剤としてｎ−オクチル−３−メルカプトプロピオン酸エステル１部で乳化したものを１〜２時間にわたって上記過硫酸カリウムの入ったフラスコ中に連続的に滴下し、シェル部とした。
【０３２６】
それから更に７５℃で２時間反応させた後５０℃に冷却しアンモニア水でｐＨ８に調整し、コアシェル構造を有する樹脂粒子Ｓ７を得た。
【０３２７】
得られた樹脂粒子Ｓ１〜Ｓ８の構成、物性等の一覧を表１に示す。
【０３２８】
【表１】

【０３２９】
《ラテックスの調製》
（ラテックス１ＨＭＬの調製）
（１）核粒子の調製（第一段重合）：
攪拌装置、温度センサー、冷却管、窒素導入装置を取り付けた５０００ｍｌのセパラブルフラスコに下記に示すアニオン系界面活性剤７．０８ｇをイオン交換水３０１０ｇに溶解させた界面活性剤溶液（水系媒体）を仕込み、窒素気流下２３０ｒｐｍの攪拌速度で攪拌しながら、フラスコ内の温度を８０℃に昇温させた。
【０３３０】
（１０１）Ｃ₁₀Ｈ₂₁（ＯＣＨ₂ＣＨ₂）₂ＯＳＯ₃Ｎａ
この界面活性剤溶液に、重合開始剤（過硫酸カリウム）９．２ｇをイオン交換水２００ｇに溶解させた開始剤溶液を添加し、温度を７５℃とした後、スチレン７０．１ｇ、ｎ−ブチルアクリレート１９．９ｇ、メタクリル酸１０．９ｇからなる単量体混合液を１時間かけて滴下し、この系を７５℃にて２時間にわたり加熱、攪拌することにより重合（第一段重合）を行い、ラテックス（高分子量樹脂からなる樹脂粒子の分散液）を調製した。これを「ラテックス（１Ｈ）」とする。
【０３３１】
（２）中間層の形成（第二段重合）；
攪拌装置を取り付けたフラスコ内において、スチレン１０５．６ｇ、ｎ−ブチルアクリレート３０．０ｇ、メタクリル酸６．２ｇ、ｎ−オクチル−３−メルカプトプロピオン酸エステル５．６ｇからなる単量体混合液に、結晶性物質として、上記１９）で表される化合物（以下、「例示化合物１９」という。）９８．０ｇを添加し、９０℃に加温し溶解させて単量体溶液を調製した。
【０３３２】
一方、アニオン系界面活性剤（上記式（１０１））１．６ｇをイオン交換水２７００ｍｌに溶解させた界面活性剤溶液を９８℃に加熱し、この界面活性剤溶液に、核粒子の分散液である前記ラテックス（１Ｈ）を固形分換算で２８ｇ添加した後、循環経路を有する機械式分散機「クレアミックス（ＣＬＥＡＲＭＩＸ）」（エム・テクニック（株）製）により、前記例示化合物１９）の単量体溶液を８時間混合分散させ、乳化粒子（油滴）を含む分散液（乳化液）を調製した。
【０３３３】
次いで、この分散液（乳化液）に、重合開始剤（ＫＰＳ）５．１ｇをイオン交換水２４０ｍｌに溶解させた開始剤溶液と、イオン交換水７５０ｍｌとを添加し、この系を９８℃にて１２時間にわたり加熱攪拌することにより重合（第二段重合）を行い、ラテックス（高分子量樹脂からなる樹脂粒子の表面が中間分子量樹脂により被覆された構造の複合樹脂粒子の分散液）を得た。これを「ラテックス（１ＨＭ）」とする。
【０３３４】
前記ラテックス（１ＨＭ）を乾燥し、走査型電子顕微鏡で観察したところ、ラテックスに取り囲まれなかった例示化合物１９）を主成分とする粒子（４００ｎｍ〜１０００ｎｍ）が観察された。
【０３３５】
（３）外層の形成（第三段重合）：
上記の様にして得られたラテックス（１ＨＭ）に、重合開始剤（ＫＰＳ）７．４ｇをイオン交換水２００ｍｌに溶解させた開始剤溶液を添加し、８０℃の温度条件下に、スチレン３００ｇ、ｎ−ブチルアクリレート９５ｇ、メタクリル酸１５．３ｇ、ｎ−オクチル−３−メルカプトプロピオン酸エステル１０．４ｇからなる単量体混合液を１時間かけて滴下した。滴下終了後、２時間にわたり加熱攪拌することにより重合（第三段重合）を行った後、２８℃まで冷却しラテックス（高分子量樹脂からなる中心部と、中間分子量樹脂からなる中間層と、低分子量樹脂からなる外層とを有し、前記中間層に例示化合物１９）が含有されている複合樹脂粒子の分散液を得た。このラテックスを「ラテックス（１ＨＭＬ）」とする。
【０３３６】
《着色粒子の調製》
（着色粒子１〜８の調製）
このラテックス（１ＨＭＬ）を構成する複合樹脂粒子は、１３８，０００、８０，０００および１３，０００にピーク分子量を有するものであり、また、この複合樹脂粒子の重量平均粒径は１２２ｎｍであった。
【０３３７】
ＳＤＳ５９．０ｇをイオン交換水１６００ｍｌに攪拌溶解し、この溶液を攪拌しながら、Ｃ．Ｉ．Ｐｉｇｍｅｎｔ ｒｅｄ １２２ ４２０．０ｇを徐々に添加し、次いで「クレアミックス」（エム・テクニック（株）製）を用いて分散処理することにより、着色剤粒子の分散液（以下「着色剤分散液１」という。）を調製した。この着色剤分散液における着色剤粒子の粒子径を、電気泳動光散乱光度計「ＥＬＳ−８００」（大塚電子社製）を用いて測定したところ、重量平均粒径で８９ｎｍであった。
【０３３８】
ラテックス１ＨＭＬ４２０．７ｇ（固形分換算）と、イオン交換水９００ｇと、１６６ｇの着色剤分散液１とを、温度センサー、冷却管、窒素導入装置、攪拌装置を取り付けた反応容器（四つ口フラスコ）に入れ攪拌した。容器内の温度を３０℃に調製した後、この溶液に５モル／リットルの水酸化ナトリウム水溶液を加えてｐＨを８〜１０．０に調整した。
【０３３９】
次いで、塩化マグネシウム・６水和物１２．１ｇをイオン交換水１０００ｍｌに溶解した水溶液を、攪拌下、３０℃にて１０分間かけて添加した。３分間放置した後に昇温を開始し、この系を６〜６０分間かけて９０℃まで昇温し、会合粒子の生成を行った。その状態で、「コールターカウンター ＴＡ−II」にて会合粒子の粒径を測定し、個数平均粒径が５μｍになった時点で、塩化ナトリウム４０．２ｇをイオン交換水１０００ｍｌに溶解した水溶液を添加して粒子成長をいったん停止し、着色粒子１を得た。
【０３４０】
また、前記凝集工程のｐＨ、熟成処理工程の温度、熟成時間、攪拌強度を制御することにより、結晶性物質、着色剤分散状態、形状および形状係数の変動係数を制御し、更に、液中分級により、トナー粒径および粒度分布の変動係数を任意に調整して、着色粒子２〜８を得た。
【０３４１】
《トナーの製造例》
（トナー１〜８の製造）
上記で得られた着色粒子１〜８に、樹脂粒子の質量（ｓ）と着色粒子の質量（Ｍｐ）との質量比（（ｓ）／（ｓ＋Ｍｐ）×１００）％が表４に記載の数値になるように調整しながら、樹脂粒子Ｓ１〜Ｓ８の分散液を各々、添加し、更に熟成処理として液温度９８℃にて２時間にわたり加熱攪拌し、塩化ナトリウム４０．２ｇをイオン交換水１０００ｍｌに溶解した水溶液を添加して粒子の熟成を成長をいったん停止し液温度９８℃にて１〜４時間にわたり加熱攪拌することにより、粒子の融着を継続させた（熟成工程）。
【０３４２】
その後、３０℃まで冷却し、塩酸を添加してｐＨを２．０に調整し、攪拌を停止した。生成した会合粒子を濾過し、４５℃のイオン交換水で繰り返し洗浄を行い、その後、４０℃の温風で乾燥し、疎水性シリカ０．８質量部、疎水性酸化チタン１．０質量部を添加し、１０リットルのヘンシェルミキサーの回転翼の周速を３０ｍ／ｓに設定し２５分間混合しトナー１〜８を得た。
【０３４３】
（比較用トナー１の製造）
また、トナー１の製造において、樹脂粒子Ｓ１の分散液を添加しない以外は、同様にして比較用トナー１を得た。
【０３４４】
なお、上記記載のトナーの製造時において、上記記載の着色粒子は、外部添加剤の添加によってその形状や粒径は全く変化しない。
【０３４５】
（比較用トナー２の製造）
樹脂粒子Ｓ１の分散液をスプレードライ法で乾燥し、樹脂粒子Ｓ１粉末を得た。
【０３４６】
（処方１）
スチレンアクリル樹脂 １００部
Ｃ．Ｉ．ｐｉｇｍｅｎｔ．ｒｅｄ １２２ １０部
樹脂粒子Ｓ１粉末 ２部
例示化合物１９） ８部
上記の組成１をヘンシェルミキサーで予備混合し、２軸押し出し混練し、ジェット式粉砕機で粉砕、気流式分級器で分級し、ついで疎水性シリカ０．８質量部、疎水性酸化チタン１．０質量部を添加し、ヘンシェルミキサーの回転翼の周速を３０ｍ／ｓに設定し２５分間混合し比較用トナー２を得た。
【０３４７】
（比較用トナー３の製造）
反応容器にトルエン１５０部を入れ還流温度まで昇温した。これにスチレン７５部、１Ｈ，１Ｈ−ペルフルオロ−ｎ−オクチルアクリレート２５質量部、及びｔｅｒｔ−ブチルパーオキシベンゾエート２部の混合液を滴下後、トルエン還流下、７時間で溶液重合を完了した。トルエンを減圧下留去し、化合物（Ａ）を得た。
【０３４８】
高速撹拌装置ＴＫ式ホモミキサー（特殊機化工業社製）を備えた２リットルの四つ口フラスコ中に、イオン交換水６００部と０．ｌｍｏｌ／リットル−Ｎａ₃ＰＯ₄水溶液５００部を投入し、回転数を１２０００ｒｐｍに調整し、７０℃に加温せしめた。ここに、１．０ｍｏｌ／リットル−ＣａＣｌ₂水溶液７０部を添加し、微小な難水溶性分散安定剤（リン酸カルシウム塩）を含む水系分散媒体を調製した。
【０３４９】
一方、分散質として
スチレン ８２部
２−エチルヘキシルアクリレート １８部
Ｃ．Ｉ．ｐｉｇｍｅｎｔ．ｒｅｄ１２２ １０部
例示化合物１９） ８部
化合物（Ａ） ２部
上記混合物を、アトライター（三井金属社製）を用い３時間分散させた後、２，２’−アゾビス（２，４−ジメチルバレロニトリル）３部を添加し重合性単量体組成物を調製した。
【０３５０】
次に、前記水系分散媒体中に該重合性単量体組成物を投入し、内温７０℃の窒素雰囲気下で、高速撹拌機の回転数を１２０００ｒｐｍに維持しつつ、１０分間撹拌し、該重合性単量体組成物を造粒した。その後、撹拌機をプロペラ撹拌羽根に換え５０ｒｐｍで撹拌しながら同温度で１０時間保持して重合を完了した。重合終了後、懸濁液を冷却し、次いで、希塩酸を添加し分散安定剤を除去せしめた。さらに水洗浄を数回繰り返した後、乾燥させ、ついで疎水性シリカ０．８質量部、疎水性酸化チタン１．０質量部を添加し、ヘンシェルミキサーの回転翼の周速を３０ｍ／ｓに設定し２５分間混合し比較用トナー３を得た。
【０３５１】
（比較用トナー４の製造）
比較用トナー１の１００部に樹脂粒子Ｓ１粉末２部を添加し、ヘンシェルミキサーで１０分間混合して、比較用トナー４を得た。
【０３５２】
上記で製造したトナー１〜８、比較用トナー１〜４の各々の物性データ（個数平均粒径、形状係数、形状係数の変動係数、角がない着色粒子の割合、個数分布の変動係数、ｍ１とｍ２の和）を表２に示す。
【０３５３】
【表２】

【０３５４】
【表３】

【０３５５】
【表４】

【０３５６】
表２に記載のトナー１〜８と着色粒子１〜８の各物性データを比較すると、物性データは同一である。その理由は、本発明に係る着色粒子の製造においては、樹脂粒子と着色剤とを塩析／融着段階および形状制御工程時にモニタリングを行い、攪拌回転数、および加熱時間等の反応制御により、形状および形状係数の変動係数を制御し、粒径および粒度分布の変動係数の調整を行う。
【０３５７】
このようにして得られた着色粒子に外部添加剤を添加してトナー粒子を製造するわけで、外添剤は単にトナー粒子の表面に固着するのみで着色粒子に物理的変化を与えないから、得られたトナー粒子の物理的特性（形状および粒径等）は着色粒子の物理的特性と同一である。
【０３５８】
《感光体Ｐ１の製造》
長さ３８０ｍｍ、直径６０ｍｍの円筒状導電性支持体上に下記の塗布液を塗布し、感光体Ｐ１を作製した。
【０３５９】
〈下引き層〉
チタンキレート化合物（ＴＣ−７５０：松本製薬社製） ３０ｇ
シランカップリング剤（ＫＢＭ−５０３：信越化学社製） １７ｇ
２−プロパノール １５０ｍｌ
上記塗布液を用いて円筒状導電性支持体上に、膜厚０．５μｍとなるよう塗布した。
【０３６０】

上記の材料を混合し、サンドミルを用いて１０時間分散し、電荷発生層塗布液を調製した。この塗布液を前記下引き層の上に浸漬塗布法で塗布し、膜厚０．２μｍの電荷発生層を形成した。
【０３６１】

上記材料を混合し、溶解して電荷輸送層塗布液を調製した。この塗布液を前記電荷発生層の上に浸漬塗布法で塗布して乾燥膜厚２０μｍの電荷輸送層を形成した。
【０３６２】
〈保護層〉
メチルトリメトキシシラン １５０ｇ
ジメチルジメトキシシラン ３０ｇ
反応性電荷輸送性化合物（例示化合物Ｂ−１） １５ｇ
ポリフッ化ビニリデン粒子（体積平均粒径０．２μｍ） １０ｇ
酸化防止剤（例示化合物２−１） ０．７５ｇ
２−プロパノール ７５ｇ
３％酢酸 ５ｇ
上記の材料を混合し、樹脂層用の塗布液を調製した。この塗布液を前記電荷輸送層の上に円形量規制型塗布装置により厚さ２μｍの樹脂層を形成し、１２０℃、１時間の加熱硬化を行い、シロキサン樹脂層を形成し、感光体Ｐ１を作製した。
【０３６３】
【化５】

【０３６４】
【化６】

【０３６５】
【化７】

【０３６６】
次いで、図５に記載の画像形成プロセスを有するデジタル複写機（コロナ帯電、レーザ露光、反転現像、静電転写、爪分離、クリーニングブレードを有する）に、感光体Ｐ１及び上記記載のトナーをそのまま現像剤として搭載し評価した。上記デジタル複写機は以下の条件に設定し評価を行った。
【０３６７】
（帯電条件）
帯電器；スコロトロン帯電器、初期帯電電位を−７５０Ｖに調整
（露光条件）
露光部電位を−５０Ｖにする露光量に設定。
【０３６８】
（現像条件）
ＤＣバイアス；−５５０Ｖ
転写極；コロナ帯電方式
また、定着装置としては、図６の装置を用いた。尚、線速は１２０ｍｍ／ｓｅｃであり、定着装置のクリーニング機構及びシリコンオイル供給機構は装着していない。定着の温度は加熱ローラーの表面温度で制御し、１６５℃の設定温度とした。
【０３６９】
複写条件は、高温高湿環境（３０℃、８０％ＲＨ）にて連続５０万コピー行い、以下の評価項目の評価を行った。
【０３７０】
評価は、画素率が７％の文字画像、人物顔写真画像、ベタ白画像、ベタ黒画像がそれぞれ１／４等分にあるオリジナル画像をＡ４中性紙での複写を行い、下記に示す評価を行った。
【０３７１】
《評価項目》
（ハーフトーンの均一性）
前述の連続５０万コピー後のトナー搬送性変動によるハーフトーン画像の均一性（ムラのなさ）を評価した。下記のように４段階に目視評価した。
【０３７２】
Ａ：ムラの無い均一な画像
Ｂ：スジ状の極めて薄いムラが存在
Ｃ：スジ状の薄いムラが数本存在するが実用上問題ないレベル
Ｄ：スジ状のはっきりしたムラが数本以上存在
評価ランクは、Ａ〜Ｃを合格、Ｄを不合格とした。
【０３７３】
（カブリ）
ベタ白画像を使用し、初期と５万枚後におけるカブリの発生を目視で評価した。評価は３ランクで行った。
【０３７４】
◎：カブリ発生なし
○：時々、カブリ発生有（実用可）
×：連続してカブリ発生
（耐オフセット性）
Ａ４サイズの転写紙に１０００枚連続印字した後、白紙を印字し、オフセットによる白紙への汚れの発生状況とヒートローラー表面のトナー汚れを目視にて評価した。なお、評価に使用する転写紙としては上質紙２００ｇ／ｍ²の厚紙を使用し、紙進行方向（熱ローラー周方向）に平行な、幅０．３ｍｍ、長さ１５０ｍｍの線画像を形成した。
【０３７５】
◎：画像オフセット、ヒートローラー上のトナー汚れ共に全く見られない
○：画像オフセット発生はないが、ヒートローラー上にトナー汚れがある
×：画像オフセットが確認される。
【０３７６】
評価ランクは、◎、○は合格、×は不合格である。
（感光体フィルミング）
前述の連続５０万コピー後の感光体表面を目視にて観察することにより、フィルミングの有無を判定した。
【０３７７】
得られた評価結果を表５に示す。
【０３７８】
【表５】

【０３７９】
表５から、比較の試料と比べて、本発明の試料は、ハーフトーンの均一性に優れ、低カブリであり、耐オフセット性が良好であり、且つ、感光体のトナーフィルミング性も極めて良好であることが明らかである。
【０３８０】
【発明の効果】
本発明により、ハーフトーンの均一性に優れ、低カブリであり、耐オフセット性が良好であり、且つ、感光体のフィルミング発生のない静電荷像現像用トナー、前記トナーの製造方法及び、前記トナーを用いた画像形成方法を提供することが出来た。
【図面の簡単な説明】
【図１】角なしまたは角ありトナーを説明する模式図である。
【図２】本発明に係る海島構造を有するトナー粒子の一例を説明する模式図である。
【図３】本発明に係る海島構造を有するトナー粒子をボロノイ多角形によって分割した模式図である。
【図４】本発明に適用される画像形成装置の一例を示す断面図である。
【図５】カラー電子写真画像形成装置の一例を示す概略断面図。
【図６】本発明で用いられる定着器の一態様を示す概略断面図である。
【図７】本発明で用いられる定着器の別の一態様を示す概略断面図である。
【図８】本発明で用いられる定着器の別の一態様を示す概略断面図である。
【図９】本発明で用いられる定着器の別の一態様を示す概略断面図である。
【符号の説明】
１、１ａ、１ｂ、１ｃ、１ｄ 静電潜像担持体（電子写真感光体ドラム、感光体ドラム）
２ａ、２ｂ、２ｃ、２ｄ ドラム帯電器
３、３ａ、３ｂ、３ｃ、３ｄ 現像器
４ａ、４ｂ、４ｃ、４ｄ 転写帯電器
４１ａ、４１ｂ、４１ｃ、４１ｄ 転写押圧部材
５ａ、５ｂ、５ｃ、５ｄ 感光体クリーニング部
１０ 定着部（定着器）
１６ａ 先端縁部
１７ レーザビーム露光装置
２１ａ、２１ｂ、２１ｃ、２１ｄ 除電露光ランプ
２２ａ、２２ｂ、２２ｃ、２２ｄ 電位センサ
１６０ 位置決め部材
Ｄａ 現像ニップ幅
Ｐａ、Ｐｂ、Ｐｃ、Ｐｄ 画像形成部
８ 画像保持体
１１ 加熱ロールの芯金
１２、２０ 加熱ロール
１２ａ 加熱ロールの被覆層
１３ 加熱部材
２１ 加圧ロールの芯金
２２ 加圧ロールの被覆層
３７ 発熱部材
３８ 離型保護層
Ｔ トナー画像
４０ 加熱部材
４１、２１１、２２１ 芯金
４２、２１２ 弾性層（シリコーン樹脂層）
４３、２１３、２２２ 離型層（フッ素樹脂層）
４４、２１４、２２３ ヒータ
４５ 温度センサ
５０ エンドレスベルト
５１〜５３ 指示ローラ
５４ ベースプレート
５５ 押圧補助パッド
５６ 押圧パッド
７１、７２ 加熱ローラ
７３、７４ 耐熱クリーニング部材
７５、７６ ヒータ
７７ オイル塗布ローラ
７８ オイル溜め
７９ サーミスタ
２１０ 加熱ローラ
２２０ 加圧ローラ[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electrostatic charge image developing toner, a method for producing the toner, and an image forming method using the toner.
[0002]
[Prior art]
Conventionally, as a non-magnetic one-component development method, for example, methods described in JP-A Nos. 63-212946, 63-271374, and No. 277453 are known. This method includes a toner conveying member (also referred to as a toner carrier), a toner layer regulating member and a toner replenishing auxiliary member, and the toner replenishing auxiliary member and the toner conveying member, and the toner layer regulating member and the toner conveying member are in contact with each other. In this system, the latent image is developed by supplying a thin non-magnetic toner to the surface of the electrostatic latent image forming body using a developing device having the above configuration. In this method, the nonmagnetic toner is charged by frictional charging between the nonmagnetic toner and the toner conveying member or the toner layer regulating member.
[0003]
When this method is used, there is a problem that if the toner is used for a long time, the toner fluidity changes, and toner conveyance unevenness easily occurs, and as a result, unevenness of the image easily occurs. Further, fog is likely to occur during long-term use, particularly under high temperature and high humidity, and this solution is required. One of the reasons for this phenomenon is that the toner is likely to be fused to the member for conveying the toner and the member for regulating the toner layer, and as a result, the triboelectric chargeability is lowered. It is considered that the charge amount of the magnetic toner decreases.
[0004]
Therefore, as a technique for improving the charging characteristics and environmental characteristics of the toner as described above, for example, as described in Japanese Patent Application Laid-Open No. 2000-310882, the number of fluorine atoms calculated from the X-ray photoelectron spectroscopy analysis of the toner The carbon atom number ratio is 0.002 to 0.300, the content of the component of 1000 or less in the molecular weight distribution is 0 to 10.0% by mass, and the circle equivalent number average diameter of the dry toner is 2 A toner having an average circularity of 0.920 to 0.995 and a circularity standard deviation of less than 0.040 is disclosed.
[0005]
However, in the toner described above, a polymerizable monomer containing a bond between a carbon atom and a fluorine atom is suspension-polymerized with a styrene monomer or the like, and the fluorine atom does not exist only on the toner surface. Therefore, the stability of the charge on the toner surface is not good, and there is a problem in terms of sharpness of image quality, and it is difficult in the manufacturing method to give the toner surface a sufficient fluorine concentration.
[0006]
JP 2000-305311 discloses a low molecular weight selected from polytetrafluoroethylene, tetrafluoroethylene-containing copolymer, fluoropolyether, and perfluoroalkyl group-containing compound having a specific average dispersed particle size and melt viscosity. An electrophotographic toner containing fine particles of a fluorine-based compound is disclosed.
[0007]
However, the toner described above is obtained by externally adding and mixing fluororesin particles to a toner produced by an emulsion polymerization method. Since the fluororesin particles are not sufficiently fixed to the toner particles, the detached fluororesin particles are removed from the photoreceptor. There is a problem that the fixing heating member is easily contaminated.
[0008]
[Problems to be solved by the invention]
An object of the present invention is to provide a toner for developing an electrostatic image having excellent halftone uniformity, low fog, good offset resistance, and no filming of a photoreceptor, a method for producing the toner, and It is another object of the present invention to provide an image forming method using the toner.
[0009]
[Means for Solving the Problems]
  The object of the present invention is as follows.4Achieved by.
[0010]
  1. Polymerizable monomer having silicon atom or fluorine atomA andPolymerizable monomer B having acidic polar groupHaving a polymer formed by polymerization withAfter the resin particles are fused to the surface of the colored particles containing the binder resin and the colorant by the salting-out / fusion method, toner particles are produced through a process of adding the hydrophobized metal oxide particles.And the polymer concentration of the polymerizable monomer A in the resin particles is uniform or continuously or discontinuously changes from the resin particle surface to the inside.An electrostatic charge image developing toner.
[0011]
2. 2. The electrostatic image developing toner according to 1 above, wherein the polymerizable monomer A is represented by the general formula (1).
[0012]
3. 2. The electrostatic image developing toner according to 1 above, wherein the polymerizable monomer A is represented by the general formula (2).
[0013]
4). The resin particles include 20% by mass to 80% by mass of the polymerization component A of the polymerizable monomer A, and 2% by mass to 20% by mass of the polymerization component B of the polymerizable monomer B. 4. The electrostatic image developing toner according to any one of 1 to 3 above.
[0014]
5. In any one of the above 1 to 4, wherein the resin particles have a volume average particle size of 30 nm to 400 nm, a softening point of 80 ° C to 170 ° C, and a Tg (glass transition temperature) of 35 ° C to 80 ° C. The toner for developing an electrostatic image according to the description.
[0015]
6). 1 to 5 above, wherein the mass ratio ((s) / (s + Mp) × 100)% of the mass (s) of the resin particles and the mass (Mp) of the colored particles is 0.2% to 12%. The toner for developing an electrostatic image according to any one of the above.
[0016]
7. 7. The electrostatic image developing toner according to any one of 1 to 6, wherein the toner has a crushing strength index of 0.1 to 0.8.
[0017]
8). The resin particles are prepared by emulsion polymerization or miniemulsion polymerization, and at the time of the polymerization reaction, at least one compound selected from thioglycerin or the compound represented by the general formula (3) is used as a chain transfer agent. 8. The toner for developing an electrostatic charge image according to any one of 1 to 7 above, which is produced through a process.
[0019]
  9.The toner contains a crystalline compound, and one or more endothermic peaks in differential thermal analysis resulting from the crystalline compound exist at 60 ° C. to 120 ° C., and the endothermic amount of the endothermic peak is 4 J / g to 30 J. / G.8The toner for developing an electrostatic image according to any one of the above.
[0020]
  10.Resin particles having a polymer having a polymerization component A of a polymerizable monomer A having a silicon atom or a fluorine atom and a polymerization component B of a polymerizable monomer B having an acidic polar group, a binder resin and a colorant A process of preparing toner particles by adding metal oxide particles hydrophobized to the surface of the colored particles, which have been fused by the salting-out / fusing method.In addition, the polymer concentration of the polymerizable monomer A in the resin particles is uniform or continuously or discontinuously changes from the resin particle surface to the inside.A method for producing a toner for developing an electrostatic charge image.
[0021]
  11.1 to9In manufacturing the electrostatic image developing toner according to any one of the above,10A toner for developing an electrostatic image, characterized by using the production method described in 1.
[0022]
  12A developing roller, and a toner supply member that supplies toner for developing an electrostatic charge image on the developing roller. A nonmagnetic toner is supplied from the toner supplying member to the developing roller, and a toner layer formed on the developing roller is formed. In the image forming method using a one-component developing device that performs development using the non-magnetic toner,9An image forming method using the electrostatic image developing toner according to any one of the above.
[0023]
  13.A latent image forming step for forming a latent image on the latent image carrier, a developing step for visualizing the latent image with toner, and a toner image formed on the latent image carrier on the transferred material In the image forming method, comprising: a transfer step of transferring; and a fixing step of heating and fixing the toner image on the transfer target member using a heating member and a pressure member.9An image forming method according to any one of the above, wherein the toner for developing an electrostatic charge image and the heating member has an elastic layer.
[0024]
  14The heating member or the pressure member is at least one of a belt.13The image forming method described in 1.
[0025]
Hereinafter, the present invention will be described in detail.
The resin particles according to the present invention have a polymerization component A of a polymerizable monomer A having a silicon atom or a fluorine atom, and a polymerization component B of a polymerizable monomer B having an acidic polar group.
[0026]
The polymerizable monomer A having a silicon atom or a fluorine atom according to the present invention will be described.
[0027]
As the polymerizable monomer A according to the present invention, monomers represented by the general formula (1) and the general formula (2) are preferably used.
[0028]
In the general formula (1), R²As the alkyl group having at least one fluorine atom represented by-(CH₂)_nAn alkyl group represented by -Rf is preferably used. Among these, n is preferably an integer of 1 to 10, more preferably 2 to 4. Rf is an alkyl group having at least one fluorine atom, and the number of carbon atoms constituting Rf is preferably 1 to 21, more preferably a linear or branched chain having 6 to 10 carbon atoms. A fluoroalkyl group or a perfluoroalkyl group is preferably used.
[0029]
In the general formula (1), R²As the alkyl group having at least one silicon atom represented by the formula:₂)_nAn alkyl group represented by -Rsi is preferably used. Among these, n is preferably an integer of 1 to 10, more preferably 2 to 4. Rsi represents a group having at least one silicon atom. Among them, a trimethoxysilyl group, a triethoxysilyl group, a monoethoxydimethylsilyl group, a methylethoxysilyl group and the like are preferably used.
[0030]
In the general formula (2), R, R^FiveExamples of the substituent having 1 to 13 carbon atoms represented by the following are branched or straight chain alkyl groups (for example, methyl group, ethyl group, propyl group, butyl group, pentyl group, iso-pentyl group, 2 -Ethyl-hexyl group, octyl group, decyl group, etc.), alkenyl group having 3 to 10 carbon atoms (for example, 2-propenyl group, 3-butenyl group, 1-methyl-3-propenyl group, 3-pentenyl group, 1-methyl-3-butenyl group, 4-hexenyl group, etc.), aralkyl groups having 7 to 10 carbon atoms (for example, benzyl group, phenethyl group, etc.) and the like.
[0031]
In the general formula (2), R^ThreeExamples of the alkyl group having 1 to 8 carbon atoms represented by general formula 1 may be branched or straight chain, but are methyl, ethyl, propyl, butyl, pentyl, iso-pentyl, 2-ethyl- A hexyl group, an octyl group, etc. are mentioned.
[0032]
Hereinafter, although the specific example of the polymerizable monomer (A) represented by the said General formula (1) or the said General formula (2) is shown, this invention is not limited to these.
[0033]
(1-1) CH₂= C (CH_ThreeCO₂CH₂CF_Three
(1-2) CH₂= C (CH_ThreeCO₂CH₂(CF₂)₂H
(1-3) CH₂= C (CH_ThreeCO₂CH₂CF₂CF_Three
(1-4) CH₂= CHCO₂CH₂CF_Three
(1-5) CH₂= CHCO₂CH₂(CF₂)₂H
(1-6) CH₂= CHCO₂CH₂CF₂CF_Three
(1-7) β- (perfluorooctylethyl) acrylate
(1-8) β- (Perfluorooctylethyl) methacrylate
(1-9) β- (perfluoroisononylethyl) acrylate
(1-10) β- (Perfluoroisononylethyl) methacrylate
(2-1) CH₂= CHCO₂CH₂CH₂-Si (OCH_Three)_Three
(2-2) CH₂= C (CH_ThreeCO₂(CH₂)_Three-Si (OCH_Three)_Three
(2-3) CH₂= CHCO₂CH₂CH₂-Si (OCH₂CH_Three)_Three
(2-4) CH₂= C (CH_ThreeCO₂(CH₂)_Three-Si (OCH_Three)_Three
(2-5) CH₂= CHCO₂CH₂CH₂-Si (OCH₂CH_Three)_Three
(2-6) CH₂= CHCO₂(CH₂)_Three-Si (OCH₂CH_Three)_Three
(2-7) CH₂= C (CH_ThreeCO₂(CH₂)_Four-Si (OCH_Three)_Three
(2-8) CH₂= CHCO₂(CH₂)_Four-Si (OCH_Three)_Three
(2-9) CH₂= C (CH_ThreeCO₂(CH₂)_Four-Si (OCH₂CH_Three)_Three
(2-10) CH₂= CHCO₂(CH₂)_Four-Si (OCH₂CH_Three)_Three
(2-11) CH₂= CHCO₂(CH₂)_Four-Si (CH_Three)₂(OCH₂CH_Three) (2-12) (CH₂= CHCO₂CH₂CH₂)₂-Si (CH_Three) (OC₂H_Five)
Moreover, in this invention, these can be used 1 type or in mixture of 2 or more types.
[0034]
The polymerizable monomer B having an acidic polar group according to the present invention will be described.
Examples of the polymerizable monomer B having an acidic polar group include an α, β-ethylenically unsaturated compound having a carboxyl group and an α, β-ethylenically unsaturated compound having a sulfo group.
[0035]
Examples of α, β-ethylenically unsaturated compounds having a carboxyl group include acrylic acid, methacrylic acid, fumaric acid, maleic acid, itaconic acid, cinnamic acid, maleic acid monobutyl ester, maleic acid monooctyl ester, And metal salts such as Na and Zn.
[0036]
Examples of the α, β-ethylenically unsaturated compound having a sulfo group include sulfonated styrene and its Na salt, allylsulfosuccinic acid, octyl allylsulfosuccinate, and Na salts thereof.
[0037]
Of these, methacrylic acid and acrylic acid are particularly preferably used. Moreover, the said compound can be used 1 type or in mixture of 2 or more types.
[0038]
The resin particles according to the present invention preferably contain a polymerization component C of other vinyl polymerizable monomer (C).
[0039]
Examples of the vinyl polymerizable monomer (C) according to the present invention include styrene monomers and (meth) acrylic acid ester monomers.
[0040]
Examples of the styrene monomer include styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, p-ethylstyrene, and pn. -Butyl styrene, p-tert-butyl styrene, pn-hexyl styrene, pn-octyl styrene, pn-nonyl styrene, pn-decyl styrene, pn-dodecyl styrene, 2,4- Examples thereof include styrene monomers such as dimethylstyrene and 3,4-dichlorostyrene and derivatives thereof.
[0041]
Examples of (meth) acrylic acid ester monomers include methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate, and methacrylic acid. Examples include butyl, hexyl methacrylate, 2-ethylhexyl methacrylate, ethyl β-hydroxyacrylate, propyl γ-aminoacrylate, stearyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, and the like.
[0042]
Examples of vinyl ester monomers include vinyl acetate, vinyl propionate, vinyl benzoate, and examples of vinyl ether monomers include vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether, vinyl phenyl ether, and the like. It is done.
[0043]
Of these, butyl acrylate and methyl methacrylate are particularly preferred.
Moreover, these can be used 1 type or in mixture of 2 or more types.
[0044]
The resin particles according to the present invention are obtained by fusing resin particles to the surface of colored particles containing a binder resin and a colorant by a salting-out / fusing method, and toner fluidity together with metal oxide particles that have been hydrophobized. Further, since the transportability is stabilized and the fusion is performed without peeling from or leaving the colored particles, the effects described in the present invention can be obtained.
[0045]
In the resin particles according to the present invention, the constituent ratio of the polymerizable component of the polymerizable monomer A, the polymerizable component of the polymerizable monomer B, and the polymerizable component of the other vinyl polymerizable monomer (C) is as follows: From the viewpoint of preferably exhibiting the effects described in the present invention, the polymerization component A of the polymerizable monomer A, the polymerization component B of the polymerizable monomer B, and the polymerization component C of the other vinyl polymerizable monomer (C). Based on the total mass, the polymerization component A is 20% by mass to 80% by mass, more preferably 25% by mass to 70% by mass, and the polymerization component B is 2% by mass to 20% by mass. % Is preferable, and more preferably 3% by mass to 12% by mass.
[0046]
Further, as described in claim 9, the concentration of the polymer A including the polymerization component of the polymerizable monomer A, which is a constituent component of the resin particle, may increase from the resin particle surface to the inside. Conversely, it may be lowered from the resin particle surface to the inside.
[0047]
In producing toner particles, it is particularly preferable that the concentration of the polymer A increases from the resin particle surface to the inside from the viewpoint of enhancing the adhesion of the resin particles to the colored particles.
[0048]
The resin particles in which the concentration of the polymer A, which is a polymerization component of the polymerizable monomer A, varies, specifically, a polymerization initiator in a dispersion obtained by mixing the polymerizable monomers A, B, and C at a certain ratio. Is added to start polymerization to produce a seed, and then the ratio of A, B, and C described above is changed with respect to the seed and added dropwise to complete the polymerization.
[0049]
As an example, after forming a core part of resin particles by adding a polymerization initiator solution to a polymerizable monomer dispersion containing A and B, a polymerizable monomer that does not contain A or is not a main component is used. It can manufacture by dripping and forming a shell part.
[0050]
Here, the polymer A which is a polymer component of the polymerizable monomer A may be a homopolymer (also referred to as a single polymer) of the polymerizable monomer A, and may be a copolymer of other polymerizable monomers. It may be combined.
[0051]
Further, the resin particles according to the present invention preferably have a discontinuous layer such as a core-shell structure. Here, the resin constituting the core resin layer or the shell resin layer is a polymerizable single component as a constituent component. It is preferable that the polymerization component of the monomer A is contained in an amount of 20% by mass to 80% by mass and the polymerization component of the polymerizable monomer B is contained in an amount of 2% by mass to 20% by mass.
[0052]
The concentration of the polymer A containing the polymerization component of the polymerizable monomer A, which is a constituent component of the resin particle as described above, is a resin particle whose concentration increases from the surface to the inside of the resin particle, or conversely low. The composition analysis of the resin particles and the resin particles having a discontinuous layer such as a core-shell structure is performed by performing X-ray photoelectron spectroscopy (also called ESCA or XPS) from the particle surface to the inside of the particle while etching from the particle surface. ) To perform measurement.
[0053]
The resin particles according to the present invention preferably have a volume average particle size of 30 nm to 400 nm, a softening point of 80 ° C. to 170 ° C., and a Tg (glass transition temperature) of 35 to 80 ° C., more preferably a volume average. The particle size is 70 nm to 120 nm, the softening point is 90 ° C. to 120 ° C., and the Tg (glass transition temperature) is 40 ° C. to 60 ° C.
[0054]
By adjusting the volume average particle diameter, softening point, and Tg (glass transition temperature) of the resin particles according to the present invention within the above ranges, the effects described in the present invention can be obtained, and a clear image can be obtained. It can be formed continuously from the beginning, and the durability of the developing member can be improved.
[0055]
The volume average particle diameter according to the present invention can be measured using a Coulter Counter TA-II, Coulter Multisizer, SLAD1000 (a laser diffraction particle diameter measuring apparatus manufactured by Shimadzu Corporation), or the like.
[0056]
The glass transition temperature (Tg) is measured by a differential calorimetric analysis method, for example, using a DSC curve. Here, it measured using DSC-7 (made by Perkin Elmer). As the measurement conditions, the temperature rise / cool condition is left at 0 ° C. for 1 minute, and then the temperature is raised to 200 ° C. at 10 ° C./min (first temperature rise process). Next, after standing at 200 ° C. for 1 minute, it is cooled to 0 ° C. under the condition of 10 ° C./min (first cooling process). Next, after standing at 0 ° C. for 1 minute, the temperature is raised to 200 ° C. under a condition of 10 ° C./min (second temperature raising process). The value in the onset method measured in the second temperature raising process, that is, the intersection of the peak base line and the peak maximum slope line was defined as the glass transition temperature.
[0057]
The softening point according to the present invention can be measured with a flow tester. After a pellet having a load of 200 N, a die diameter of 1 mm, a diameter of 10 mm, and a height of 12 mm is left at 80 ° C. for 300 seconds, it is measured by a 5 mm offset method at a temperature rising rate of 6 ° C./min.
[0058]
Further, these resins preferably have a molecular weight measured by gel permeation chromatography of 1,000 to 100,000 in terms of number average molecular weight (Mn) and 2000 to 1,000,000 in terms of weight average molecular weight (Mw). Further, the molecular weight distribution is preferably such that Mw / Mn is 1.5 to 100, particularly 1.8 to 70.
[0059]
The production of the resin particles according to the present invention is preferably produced by an emulsion polymerization method or a mini-emulsion polymerization method, more preferably by using a chain transfer agent represented by the general formula (3) at the time of polymerization. The molecular weight and molecular weight distribution of the resin described above can be adjusted to a preferable range.
[0060]
Here, the emulsion polymerization method or miniemulsion polymerization method used for the production of the resin particles according to the present invention will be described.
[0061]
The emulsion polymerization method used in the present invention is a homogenizer or the like in the presence of an emulsifier (also referred to as a surfactant) having a monomer (also referred to as a monomer) at a concentration equal to or higher than a critical micelle formation concentration (hereinafter abbreviated as CMC). This is a method of emulsifying and dispersing by the mechanical dispersion means, then adding mainly a water-soluble polymerization initiator, polymerizing to form resin fine particles, and then producing resin particles of a desired size by association.
[0062]
The miniemulsion polymerization method used in the present invention is one form of an emulsion polymerization method and emulsifies with an emulsifier concentration of CMC or less. The polymerization initiator used at this time may be either water-soluble or oil-soluble. For example, an oil-soluble polymerization initiator or a functional compound is allowed to coexist with a polymerizable monomer, and the machine is used in the presence of an emulsifier having a concentration of CMC or lower. By dispersing and polymerizing the polymer particles, molecular diffusion of the functional additive and the like in the monomer particles is suppressed, and the polymerization proceeds only in the monomer oil droplets. It is particularly preferable because resin particles reliably contained therein can be obtained.
[0063]
Specifically, in each of the above polymerization methods, a monomer solution in which a chain transfer agent and, if necessary, a release agent are dissolved is dispersed in an aqueous medium, and then the molecular weight of the chain transfer agent in each polymerization method. After adjustment is made and resin particles containing a release agent or the like are prepared as necessary, the resin particles are applied to the surface of the colored particles containing a binder resin and a colorant by a salting-out / fusion method. The toner for electrostatic image development of the present invention is prepared by preparing toner particles through a step of adding metal oxide particles that have been subjected to hydrophobization treatment after being used and fused.
[0064]
The chain transfer agent represented by the general formula (3) used when producing the resin particles of the present invention will be described.
[0065]
In the general formula (3), R⁶Examples of the divalent hydrocarbon group having 1 to 10 carbon atoms represented by the following include an alkylene group, an alkenylene group, an alkynylene group, and the like. Specifically, an ethylene group, a propylene group, a butylene group, a trimethylene group, Examples include a tetramethylene group, a pentamethylene group, an octamethylene group, a hexamethylene group, an ethylethylene group, a propenylene group, and a vinylene group.
[0066]
These substituents may be unsubstituted or may further have a substituent.
In the general formula (3), R⁷As the hydrocarbon group having 2 to 15 carbon atoms represented by, for example, a branched or straight chain alkyl group (for example, methyl group, ethyl group, propyl group, butyl group, pentyl group, iso-pentyl group, 2 -Ethyl-hexyl group, octyl group, decyl group, etc.), alkenyl group (for example, 2-propenyl group, 3-butenyl group, 1-methyl-3-propenyl group, 3-pentenyl group, 1-methyl-3-butenyl) Group, 4-hexenyl group, etc.), aralkyl group (for example, benzyl group, phenethyl group, etc.).
[0067]
Preferred examples of the compound represented by the general formula (3) include thioglycolic acid esters and 3-mercaptopropionic acid esters. Specific examples of thioglycolic acid esters include ethyl thioglycolate, butyl thioglycolate, t-butyl thioglycolate, 2-ethylhexyl thioglycolate, octyl thioglycolate, isooctyl thioglycolate, decyl thioglycolate Thioglycolate dodecyl, ethylene glycol thioglycolate, neopentyl glycol thioglycolate, trimethylolpropane thioglycolate, pentaerythritol thioglycolate, sorbitol thioglycolate Examples of 3-mercaptopropionic acid esters include ethyl ester, octyl ester, decyl ester, dodecyl ester, pentaerythritol tetrakisester , Ethylene glycol 3-mercaptopropionate, neopentyl glycol 3-mercaptopropionate, trimethylolpropane 3-mercaptopropionate, pentaerythritol 3-mercaptopropionate, sorbitol 3-mercaptopropionate Examples include esters.
[0068]
Among the chain transfer agents, 3-mercaptopropionate is more preferably used, but n-octyl-3-mercaptopropionate is particularly preferably used.
[0069]
As a usage-amount of the chain transfer agent represented by the said General formula (3), 0.01 mass%-5 mass% of a polymerizable monomer are preferable, More preferably, 0.03 mass%-3 mass% It is.
[0070]
The resin particles according to the present invention are preferably prepared by the emulsion polymerization method and the mini-emulsion polymerization method described above, but the polymerization initiator used for initiating the polymerization reaction is preferably a water-soluble initiator, for example, Persulfates (for example, potassium persulfate, ammonium persulfate, etc.), azo compounds (for example, 4,4′-azobis-4-cyanovaleric acid and its salts, 2,2′-azobis (2-amidinopropane) salts, etc. ), Peroxide compounds and the like. Furthermore, the radical polymerization initiator can be combined with a reducing agent as required to form a redox initiator. By using a redox initiator, the polymerization activity can be increased, the polymerization temperature can be lowered, and the polymerization time can be shortened.
[0071]
The polymerization temperature is not particularly limited as long as it is equal to or higher than the lowest radical generation temperature of the polymerization initiator, but it is, for example, in the range of 50 ° C to 90 ° C. However, it is also possible to polymerize at room temperature or higher by using a polymerization initiator that is started at room temperature in combination with hydrogen peroxide / reducing agent (ascorbic acid or the like).
[0072]
The reaction temperature varies depending on the monomer used, the type of polymerization initiator, and the like, but a temperature range of 30 to 80 ° C. is usually preferable. Moreover, although reaction time is until the time of a monomer component lose | disappearing, 3 to 20 hours are preferable normally. In addition, pH which superposes | polymerizes is performed in a weakly acidic atmosphere, and 4-6 are preferable. The solid content is 25% or more, preferably 35% or more.
[0073]
The electrostatic image developing toner (hereinafter also simply referred to as toner) according to the present invention will be described.
[0074]
In the toner of the present invention, the above-mentioned resin particles are fused to the surface of colored particles containing a binder resin and a colorant by a salting-out / fusing method, and then hydrophobized metal oxide particles are added. It is characterized by being manufactured through the process of performing.
[0075]
The metal oxide particles according to the present invention will be described.
Examples of the constituent material of the metal oxide particles according to the present invention include silicon oxide, titanium oxide, aluminum oxide, zinc oxide, zirconium oxide, cerium oxide, tungsten oxide, antimony oxide, copper oxide, tellurium oxide, and manganese oxide. However, among these, titanium oxide is preferably used.
[0076]
In addition, as the hydrophobic treatment of the metal oxide particles described above, a coating treatment with a metal oxide such as aluminum, silicon, or zinc, or a hydrophobic treatment with an organic substance such as various coupling agents or fatty acid compounds is performed. It is preferable.
[0077]
A silane coupling agent, which is an example of a coupling agent, is used for improving the degree of hydrophobicity, environment dependency, and fluidity, and may be water-soluble.
[0078]
Such silane coupling agents include chemical structural formula R_nSiX_4-n(In the formula, n is an integer of 0 to 3, R represents an organic group such as a hydrogen atom, an alkyl group and an alkenyl group, and X represents a hydrolytic group such as a chlorine atom, a methoxy group and an ethoxy group.) And any type of chlorosilane, alkoxysilane, silazane, and special silylating agent can be used, and alkoxysilane is particularly preferable. Examples of the alkoxysilane include vinyltrimethoxysilane, propyltrimethoxysilane, i-butyltrimethoxysilane, n-butyltrimethoxysilane, n-hexyltrimethoxysilane, n-octyltrimethoxysilane, and n-dodecyltrimethoxy. Silane, phenyltrimethoxysilane, 3-glycoxypropyltrimethoxysilane and the like can be mentioned, and those having 2 to 10 carbon atoms in the hydrocarbon group are preferable. Of these, i-butyltrimethoxysilane and n-butyltrimethoxysilane are particularly preferable.
[0079]
Moreover, the said processing amount is 10-100 mass% with respect to 100 mass% of a metal oxide, Preferably it is the range of 20-70 mass%.
[0080]
Further, from the viewpoint of improving transferability, reducing separation from toner particles, and preventing contamination of the charging member and the transfer member, the number average particle size of the metal oxide particles according to the present invention is 35 to 140 nm. However, those having a range of 50 to 110 nm are preferably used. Here, the number average particle size of the metal oxide particles can be measured using a Coulter Counter TA-II, Coulter Multisizer, SLAD1000 (a laser diffraction particle size measuring device manufactured by Shimadzu Corporation) or the like.
[0081]
The toner of the present invention has a crushing strength index defined as follows of 0.1 in order to obtain effects such as low fog, offset resistance, filming of the photoreceptor, and no increase in the minimum fixing temperature. It is preferable that it is -0.8, More preferably, it is 0.2-0.5.
[0082]
Here, in the present invention, the “crushing strength index” is an index indicating the ease of crushing of toner particles, and represents an index obtained by the following method.
[0083]
(Measurement method of crushing strength index of toner)
30 g of toner (sample) and 100 g of glass beads “GB503M” (manufactured by Toshiba Barotini Co., Ltd., particle size: 2 mm) are placed in a 2 liter polyethylene pot, mixed and stirred for 60 seconds by a turbuler mixer, and then a 330 mesh test sieve. Separate and remove the glass beads. Then, before and after mixing and stirring, the number ratio (%) of small particles of 2 to 4 μm in all toner particles is measured, and calculated by the following formula.
[0084]
Crushing strength index = (N−N₀) / 60
In the formula, N is the number% of small particles of 2 to 4 μm after mixing and stirring.₀Is the number% of small particles of 2 to 4 μm before mixing and stirring.
[0085]
The “number% of small particles” is a value measured using a Coulter Multisizer. Specifically, a Coulter Multisizer is used, and an interface (manufactured by Nikkaki Co., Ltd.) that outputs a particle size distribution is connected to a personal computer. The aperture in the Coulter Multisizer was 100 μm, and the volume distribution of toner of 2 μm or more (for example, 2 to 40 μm) was measured and calculated.
[0086]
Next, the shape of the toner of the present invention will be described in detail.
The toner particles used in the present invention preferably have a variation coefficient of shape factor of 16% or less, more preferably the number in the number particle size distribution, in order to obtain developability, fine line reproducibility, and stable cleaning properties. The coefficient of variation is 27% or less.
[0087]
The shape factor of the toner of the present invention will be described. In the toner of the present invention, the proportion of toner particles having a shape factor in the range of 1.2 to 1.6 is 65 number% or more, the variation coefficient of the shape factor is 16% or less, and the number in the number particle size distribution. The coefficient of variation is 27% or less. Here, the shape factor of the toner of the present invention is represented by the following formula, and indicates the degree of roundness of the toner particles.
[0088]
Shape factor = ((maximum diameter / 2)²× π) / projection area
Here, the maximum diameter refers to the width of a particle that maximizes the interval between the parallel lines when the projected image of the toner particles on the plane is sandwiched between two parallel lines. The projected area refers to the area of the projected image of the toner particles on the plane. In the present invention, this shape factor is obtained by taking a photograph in which the toner particles are magnified 2000 times with a scanning electron microscope, and then using “SCANNING IMAGE ANALYZER” (manufactured by JEOL Ltd.) based on this photograph. It was measured by performing analysis. At this time, the shape factor of the present invention was measured by the above formula using 100 toner particles.
[0089]
The variation coefficient of the shape factor of the toner particles will be described.
“Variation coefficient of shape factor”, which is a variable indicating the uniform shape of toner particles, is calculated from the following equation.
[0090]
Variation coefficient of toner shape factor = (S1 / K) × 100 (%)
In the formula, S1 represents the standard deviation of the shape factor of 100 toner particles, and K represents the average value of the shape factor.
[0091]
As a basic condition for achieving high image quality, the toner particle shape coefficient variation coefficient of the present invention is preferably 16% or less. However, in order to promote higher image quality, the shape factor variation The coefficient is preferably 14% or less.
[0092]
In order to uniformly control the shape factor of the toner and the variation coefficient of the shape factor without variation of lots, the resin particles (polymer particles) constituting the toner of the present invention are prepared (polymerized), and the resin particles are fused. In the step of controlling the shape, an appropriate process end time is determined while monitoring the characteristics of the toner particles (colored particles) being formed.
[0093]
The number particle size distribution and the number variation coefficient of the toner of the present invention will be described.
The number particle size distribution and the number variation coefficient of the toner according to the present invention are measured by a Coulter Counter TA-II or Coulter Multisizer (manufactured by Coulter Inc.). In the present invention, a Coulter multisizer was used, and an interface (manufactured by Nikka Kisha Co., Ltd.) for outputting the particle size distribution and a personal computer were connected. The aperture used in the Coulter Multisizer was 100 μm, and the volume diameter and number diameter of 2 μm or more were measured to calculate the particle size distribution and average particle size. The number particle size distribution represents the relative frequency of toner particles with respect to the particle size, and the number average particle size represents a cumulative 50% diameter in the number particle size distribution, that is, Dn50.
[0094]
The number variation coefficient in the toner number particle size distribution is calculated from the following equation.
Number variation coefficient = [S / Dn] × 100 (%)
In the formula, S represents the standard deviation in the number particle size distribution, and Dn represents the number average particle size (μm).
[0095]
The number variation coefficient of the toner of the present invention is preferably 27% or less, and more preferably 25% or less. By adjusting the number variation coefficient to 27% or less, voids in the transferred toner layer are reduced, fixing properties are improved, and offset is less likely to occur. In addition, it is possible to obtain preferable effects such as sharp charge amount distribution, high transfer efficiency, and improved image quality.
[0096]
Although the method for controlling the number variation coefficient is not particularly limited, for example, a method of classifying toner particles by wind force can be used, but classification in liquid is effective for reducing the number variation coefficient. . Examples of the method of classifying in the liquid include a method of using a centrifuge and controlling the number of rotations to separate and collect toner particles according to the difference in sedimentation speed caused by the difference in toner particle diameter.
[0097]
In addition, as a result of investigations by focusing on the minute shape of each toner particle, the present inventors have changed the shape of the corner of the toner particle to become round inside the developing device. It was found that the burial of the agent was promoted, and the change in charge amount, fluidity, and transport stability were reduced. When the toner particles are charged by frictional charging, it is presumed that the external additive tends to be buried particularly at the corners, and the toner particles are likely to be non-uniformly charged. That is, by using toner composed of toner particles in which the number of toner particles having no corners is 50% by number or more and the number variation coefficient in the number particle size distribution is controlled to 27% or less, developability and fine line reproduction are also achieved. It has been found that a high-quality image can be formed over a long period of time.
[0098]
Further, it has been found that even when the toner is made to have a specific shape, the external additive is not buried and the charge amount distribution becomes sharp. That is, even when toner having a shape factor of 1.2 to 1.6 in which the proportion of toner particles is 65% by number or more and the variation coefficient of the shape factor is 16% or less, developability, fine line It has been found that images with excellent reproducibility and high image quality can be formed over a long period of time.
[0099]
Regarding the toner of the present invention, toner particles having no corners will be described. Here, the toner particles having no corners refer to toner particles that do not substantially have protrusions that concentrate electric charges or protrusions that easily wear due to stress, that is, as shown in FIG. When the major axis of the toner particle T is L, the circle C having a radius (L / 10) rolls inward while touching the inner line at one point with respect to the peripheral line of the toner particle T. A case where the toner does not substantially protrude outside the toner T is referred to as “toner particles having no corners”. “A case where the protrusion does not substantially protrude” refers to a case where the protrusion having the protruding circle is one or less.
[0100]
The “major diameter of toner particles” refers to the width of a particle that maximizes the interval between the parallel lines when the projected image of the toner particles on a plane is sandwiched between two parallel lines. FIGS. 1B and 1C show projected images of toner particles having corners, respectively.
[0101]
The measurement of toner without corners was performed as follows. First, an enlarged photograph of the toner particles is taken with a scanning electron microscope, and further enlarged to obtain a 15,000-fold photographic image. The photographic image is then measured for the presence or absence of the corners. This measurement was performed on 1000 toner particles.
[0102]
In the toner of the present invention, the proportion of toner particles having no corners is preferably 50% by number or more, and more preferably 70% by number or more. When the ratio of toner particles having no corners is 50% by number or more, generation of fine particles is less likely to occur due to stress with the developer conveying member and the like, and so-called contamination on the surface of the developer conveying member is suppressed. The charge amount distribution becomes sharp, the chargeability is stable, and the effect that a good image quality can be formed over a long period of time is amplified.
[0103]
A method for obtaining toner having no corners is not particularly limited. For example, as described above as a method for controlling the shape factor, a method in which toner particles are sprayed into a hot air stream, a method in which toner particles are repeatedly applied with mechanical energy by impact force in a gas phase, or a toner is dissolved. It can be obtained by adding in a solvent that does not, and applying a swirling flow.
[0104]
Further, the toner according to the present invention has a natural logarithm lnD on the horizontal axis when the particle diameter of the toner particles is D (μm), and the horizontal axis is divided into a plurality of classes at intervals of 0.23. In the histogram showing the particle size distribution, the sum (M1) of the relative frequency (m1) of the toner particles included in the most frequent class and the relative frequency (m2) of the toner particles included in the most frequent class after the most frequent class. ) Is preferably 70% or more.
[0105]
When the sum (M) of the relative frequency (m1) and the relative frequency (m2) is 70% or more, the dispersion of the particle size distribution of the toner particles becomes narrow. Therefore, selective development can be performed by using the toner in the image forming process. Can be reliably suppressed.
[0106]
In the present invention, the histogram showing the particle size distribution based on the number is a natural logarithm lnD (D: particle size of individual toner particles) having a plurality of classes (0 to 0.23: 0.23) at intervals of 0.23. 0.46: 0.46-0.69: 0.69-0.92: 0.92-1.15: 1.15-1.38: 1.38-1.61: 1.61-1. 84: 1.84 to 2.07: 2.07 to 2.30: 2.30 to 2.53: 2.53 to 2.76, and so on). This histogram was created by transferring the particle size data of the sample measured by the Coulter Multisizer to the computer via the I / O unit according to the following conditions and using the particle size distribution analysis program in the computer. is there.
[0107]
〔Measurement condition〕
1: Aperture: 100 μm
2: Sample preparation method: Electrolytic solution [ISOTON II (manufactured by Coulter Scientific Japan)] A suitable amount of a surfactant (neutral detergent) is added to 50 to 100 ml and stirred, and 10 to 20 mg of a measurement sample is added thereto. This system is prepared by dispersing for 1 minute with an ultrasonic disperser.
[0108]
Next, the particle diameter of the toner of the present invention will be described. The toner used in the present invention has a number average particle diameter of 2 to 9 [mu] m, preferably 4.0 to 8.5 [mu] m, and more preferably 4.5 to 8 [mu] m. This particle size can be controlled by the concentration of the flocculant (salting-out agent), the amount of organic solvent added, the fusing time, and the polymer composition in the toner production method.
[0109]
When the number average particle size is 2 to 9 μm, the transfer efficiency is increased, the image quality of halftone is improved, and the image quality of fine lines and dots is improved. Calculation of the particle size distribution of the toner and measurement of the number average particle size are performed using a Coulter Counter TA-II, Coulter Multisizer (both manufactured by Coulter), SLAD1100 (a laser diffraction particle size measuring device manufactured by Shimadzu Corporation), and the like. Can be measured. In the present invention, a Coulter Multisizer is used to measure and calculate an interface (manufactured by Nikkaki Co., Ltd.) that outputs a particle size distribution and a personal computer.
[0110]
The toner particles according to the present invention preferably have a sea-island structure.
The toner particles having a sea-island structure means that regions having different luminance can be confirmed in the toner particles in a cross-sectional photograph of the toner particles taken with a transmission electron microscope. That is, the toner particles according to the present invention can be obtained by the transmission electron microscope in the form of granular islands (crystalline substance phase and colorant phase) having different luminance in the continuous phase (the phase of the binder resin forms the sea). Phase) and the like.
[0111]
Further, from the observation result of the electron microscope, factors specifying the sea-island structure in the toner particles such as the number of islands in one toner particle, the shape factor of the island, and the ferret horizontal diameter of the island can be obtained as numerical values.
[0112]
Here, the luminance in the transmission electron micrograph is the electron generated due to the difference in the crystalline state of each element constituting the toner particles, that is, the binder resin, the colorant, and other crystalline substances used as additives. This is caused by visualizing the difference in the line transmittance. Generally, the colorant is photographed at low brightness because the electron beam transmittance is lower than that of the binder resin, and the crystalline substance is closer to the brightness than the binder resin. Tend to be filmed.
[0113]
In an electron micrograph, low luminance means that the luminance signal of a pixel (pixel) is in 0 to 99 gradations when divided into 256 gradations, and medium luminance is in the range of 80 to 160 gradations, High brightness refers to one having 127 to 255 gradations, but in the present invention, it is only necessary to be relative, that is, to be able to discriminate the constituent elements of the toner particles described above by a photograph, and is not necessarily limited to the above range. It is not something. For example, when an island of a crystalline substance is placed in an environment at 80 to 120 ° C. for observation with a transmission electron microscope, it flows out and is observed as a void, so that it can be easily distinguished from an island of a colorant. .
[0114]
In this way, in the present invention, each component in the toner particles is identified based on the brightness, so that it is possible to visually determine and identify the sea as an ocean and the island as an island by an electron micrograph. The luminance information is converted into image information that can be visually identified by an image analysis device installed in the electron microscope device.
[0115]
In the toner of the present invention, toner particles having a sea-island structure are preferable, and toner particles having a region where no island is present in the region along the outer periphery of the toner particle are preferably used. The toner particles having the sea-island structure as described above will be specifically described with reference to the schematic cross-sectional view of the toner particles shown in FIG.
[0116]
In the schematic cross-sectional view of FIG. 2, the region indicated by the length a and the depth b along the outer periphery of the toner particle cross-section is a region not including an island.
[0117]
In the toner particle according to the present invention, a toner particle having a region which does not include an island part having a depth of 100 to 200 nm and a length of 500 to 6000 nm in the region along the outer periphery of the toner particle cross section is preferably used.
[0118]
In this way, by not allowing islands to exist in specific areas along the outer periphery of the toner particles, it is possible to effectively prevent the islands from spilling from the toner particles, and further, crystalline substances added to the toner particles and coloring It is presumed that the agent can be appropriately dispersed in the particles and the crystalline substance can be effectively leached during pressure fixing.
[0119]
The toner particles according to the present invention preferably have a sea-island structure from the result of observation with a transmission electron microscope, but the crystalline substance added to the toner particles (for example, the release agent described above) is crystalline. Island of substance is formed, and the colorant is formed of island of colorant. Thus, it is preferable that a plurality of types of islands are formed for each kind of additive. The characteristics described so far are those of the same type, that is, between the islands of the crystalline material or between the islands of the colorant and not between different islands.
[0120]
The islands with different additives, that is, the islands of the crystalline material and the islands of the colorant are different in brightness, so that they can be easily identified in the electron micrograph, and the image analysis device for calculating the above-mentioned characteristics is erroneous. It is set so that the characteristic value between different islands is not calculated. Regarding the islands in the toner particles of the present invention, the islands of the crystalline substance are specified by the ferret diameter, the shape factor of the islands, the number of islands present per toner particle, and the islands of the colorant are This is specified by the area of the Voronoi polygon described later.
[0121]
The transmission electron microscope apparatus capable of observing the structure of the toner particles of the present invention is usually sufficiently observed by a model well known among those skilled in the art. For example, “LEM-2000 type (manufactured by Topcon Corporation)”, etc. Is used. In the present invention, values obtained from the results of transmission electron micrographs such as the number of island portions in the toner particles characterized by the present invention from the projection surface of 1000 or more toner particles at a magnification of 10,000 times. It is calculated.
[0122]
In the present invention, a photographing method using a transmission electron microscope is performed by a generally known method performed when measuring toner particles. That is, as a specific method for measuring the tomographic plane of the toner, the toner may be sufficiently dispersed in a room temperature curable epoxy resin, then embedded and cured, or dispersed in a styrene fine powder having a particle size of about 100 nm. After pressure forming, the block obtained was dyed with ruthenium tetroxide or osmium tetroxide if necessary, and then a flaky sample was cut out and transmitted using a microtome with diamond teeth The tomographic morphology of the toner was photographed using an electron microscope (TEM). The shape of the crystalline substance region in the toner particles is visually confirmed from the photograph, and an image taken by an image processing apparatus “Luzex F” (manufactured by Nireco Corporation) provided in the electron microscope apparatus. By calculating the information, the value of the Voronoi polygon of the island portion in the toner particle is obtained.
[0123]
By the above method, the structure such as the sea-island structure of the toner particles according to the present invention is specified.
[0124]
In the present invention, the crystalline substance constituting the island portion is an organic compound having a melting point, and is preferably a hydrocarbon compound containing an ester group in its compound structure. The melting point of the crystalline substance in the toner particles of the present invention is preferably a temperature lower than the softening point of the toner, specifically 130 ° C. or less. The organic compound preferably has an ester group in its structure, and includes a crystalline polyester compound.
[0125]
In the toner of the present invention, a method for confirming that the crystalline substance constituting the island portion has a melting point includes DSC. Some having crystallinity can be confirmed by means such as an X-ray diffractometer.
[0126]
In addition, the crystalline substance contained in the toner of the present invention includes those that exhibit a function as a release agent during image formation.
[0127]
In the toner of the present invention, the crystalline material preferably has a melting point of 50 to 130 ° C. in order to lower its melt viscosity and improve adhesion to a transfer material such as paper and offset resistance. More preferably, it is 60 degreeC-120 degreeC.
[0128]
Here, the melting point of the crystalline substance is a value measured by a differential calorimeter (DSC). Specifically, the temperature is raised from 0 ° C. to 200 ° C. under the condition of 10 ° C./min (first temperature rise). The temperature showing the maximum peak of the endothermic peak measured during the process is defined as the melting point. This melting point coincides with the “endothermic peak (P1) in the first temperature rising process by DSC” described later.
[0129]
As a specific measuring device of the melting point, DSC-7 manufactured by PerkinElmer, Inc. can be exemplified. The specific method for measuring the melting point with a differential calorimeter (DSC) is as follows. As the temperature rise / cooling condition, the sample was left at 0 ° C. for 1 minute, then heated to 200 ° C. at 10 ° C./min. The temperature showing the maximum endothermic peak measured at this time is defined as an endothermic peak P1 in the first temperature raising process. Then, after standing at 200 ° C. for 1 minute, the temperature is lowered under the condition of 10 ° C./min, and the temperature showing the maximum exothermic peak measured at that time is defined as the exothermic peak P2 in the first cooling process.
[0130]
The crystalline substance used in the toner of the present invention preferably has an endothermic peak (P1) in the first temperature rising process by DSC at 60 ° C. to 120 ° C., particularly 65 ° C. to 100 ° C. The endothermic amount of P1 is preferably 4 J to 30 J / g.
[0131]
By including a crystalline substance having the above thermal characteristics, it is possible to exhibit an excellent offset prevention effect (wide fixing temperature range) and an excellent fixing property (high fixing rate). In order to exert the effect of the present invention, it is preferable that the binder resin and the crystalline substance are present in a phase-separated state.
[0132]
That is, the crystalline substance dissolves sharply, and as a result, the melt viscosity of the entire toner can be lowered, and the fixability can be improved. Further, since they are phase-separated from each other, it is possible to suppress a decrease in elastic modulus on the high temperature side, so that the offset resistance is not impaired.
[0133]
The toner used in the present invention is preferably a toner in which resin particles containing a crystalline substance are fused in an aqueous medium and the crystalline substance is appropriately aggregated by an aging process to form a sea-island structure. . As described above, the resin particles containing the crystalline substance in the resin particles are salted out / fused in the aqueous medium with the colorant particles, whereby a toner in which the crystalline substance is finely dispersed can be obtained. Here, the aging step refers to a step in which stirring is continued in the range of the melting point of the crystalline substance ± 20 ° C. even after the resin particles are fused.
[0134]
In the toner of the present invention, low molecular weight polypropylene (number average molecular weight = 1500 to 9000), low molecular weight polyethylene and the like are preferable as the crystalline substance having a releasing function, and particularly preferable is an ester compound represented by the following formula: It is.
[0135]
R₁-(OCO-R₂)_n
In the formula, n is an integer of 1 to 4, preferably 2 to 4, more preferably 3 to 4, and particularly preferably 4. R₁, R₂Each represents a hydrocarbon group which may have a substituent. R₁Has 1 to 40 carbon atoms, preferably 1 to 20 carbon atoms, more preferably 2 to 5 carbon atoms. R₂Has 1 to 40 carbon atoms, preferably 16 to 30 carbon atoms, more preferably 18 to 26 carbon atoms.
[0136]
Next, the example of a typical compound is shown below.
[0137]
[Chemical 3]

[0138]
[Formula 4]

[0139]
In the present invention, crystalline polyester can also be used as the crystalline substance. As the crystalline polyester, aliphatic diol and aliphatic dicarboxylic acid (including acid anhydride and acid chloride) are used. Polyester obtained by reaction is preferred.
[0140]
Examples of the diol used to obtain the crystalline polyester include ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, and 1,4-butenediol. , Neopentyl glycol, 1,5-pentane glycol, 1,6-hexanediol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, bisphenol A, bisphenol Z, hydrogenated bisphenol A and the like.
[0141]
Dicarboxylic acids used to obtain crystalline polyesters include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, speric acid, azelaic acid, sebacic acid, maleic acid, fumaric acid, citraconic acid , Itaconic acid, glutamic acid, n-dodecyl succinic acid, n-dodecenyl succinic acid, isododecyl succinic acid, isododecenyl succinic acid, n-octyl succinic acid, n-octenyl succinic acid, acid anhydrides or acid chlorides thereof Can be mentioned.
[0142]
Particularly preferred crystalline polyesters include polyesters obtained by reacting 1,4-cyclohexanedimethanol and adipic acid, polyesters obtained by reacting 1,6-hexanediol and sebacic acid, ethylene glycol and succinic acid. And polyester obtained by reacting ethylene glycol and sebacic acid, polyester obtained by reacting 1,4-butanediol and succinic acid, among these, Most preferred is a polyester obtained by reacting 1,4-cyclohexanedimethanol and adipic acid.
[0143]
The amount of the compound added is 1 to 30% by mass, preferably 2 to 20% by mass, and more preferably 3 to 15% by mass with respect to the whole toner.
[0144]
As the toner particles of the present invention, particles having a sea-island structure in which a colorant or the like constitutes a separated phase in the binder resin phase are preferably used. The occupancy state of the island portion in the sea-island structure of toner particles is indicated by the area of a Voronoi polygon obtained by Voronoi division.
[0145]
Further, since the effects described in the present invention, such as an improvement in transfer rate, uniformity of halftone, and elimination of fine dot dust, are obtained, the toner particles according to the present invention are defined as follows. It is preferable that the average value of the area of the Voronoi polygon (also referred to as a Voronoi polyhedron) falls within a specific range. Here, the Voronoi polygon will be described.
[0146]
The area of the Voronoi polygon according to the present invention indicates the occupation state of the island portion in the toner particles. A Voronoi polygon or Voronoi polyhedron is, for example, a perpendicular bisector of adjacent points when many points are dispersed in space or on a plane, as described in the Iwanami Physical and Chemical Dictionary, By creating a perpendicular bisector, the entire space is divided into polyhedrons, or the entire plane is divided into polygons. The polyhedrons formed in this way are called Voronoi polyhedrons, and polygons are called Voronoi polygons. And the division of the plane is called Voronoi division.
[0147]
FIG. 3 shows an example of toner particles according to the present invention divided by Voronoi polygons (Voronoi polyhedron).
[0148]
That is, in the present invention, focusing on the center of gravity of the islands present in the toner particles, polygons are formed by vertical bisectors formed by connecting the centers of gravity of adjacent islands, and the areas of these polygons are transmitted through the transmission area. Calculation is performed by an image analysis apparatus installed in the electron microscope apparatus based on a photograph taken by a scanning electron microscope.
[0149]
Here, the large area of the Voronoi polygon means that the distance between the centroids of adjacent islands is separated, that is, the sparse state of the occupied state of the island part in the particle It shows the thing. A small Voronoi polygon has a short distance between the centroids of adjacent islands, that is, the islands in the particles are densely occupied.
[0150]
In the present invention, about the Voronoi polygon of the island part in a toner particle, it measured about 1000 toners, and calculated the average value of the area of a Voronoi polygon.
[0151]
In addition, when the Voronoi polygon is generally defined mathematically, it is defined by the following formula.
[0152]
《Voronoi Polygon Area》
The set of Voronoi polygons V (i) for N independent points P (i) (1 ≦ i ≦ N) in the two-dimensional space R2 or the three-dimensional space R3 is
V (i) = {X || X · P (i) | <| X · P (j) |
for all i to j}
In the equation, X and P are position vectors, and || represents a distance in Euclidean space.
[0153]
V (i) defined in this way is assumed to form a Voronoi polygon in R2 and a Voronoi polyhedron in R3, and when V (i) and V (j) are adjacent, the boundary of the Voronoi polygon is It is defined as a part of a perpendicular bisector of a line segment connecting P (i) and point P (j). The Euclidean space is as defined and described in the Mathematical Science Dictionary.
[0154]
Further, the center of gravity of the toner particles of the present invention and the center of gravity of each island in the toner particles are obtained by the moment of the image, and are automatically calculated by the image analysis apparatus installed in the transmission electron microscope apparatus. Here, the barycentric coordinates of the toner particles are obtained by multiplying the brightness value of a minute area at an arbitrary point of the toner particles by the coordinate value of the arbitrary point. Then, the product of the brightness and the coordinate value is obtained for all coordinates existing in the entire toner particles, and the sum of the products is the brightness of the toner particles (the sum of the brightness values at the respective coordinate points obtained as described above). It is required by dividing. Similarly, for the center of gravity of the island, the center of gravity of the island is also calculated by obtaining the luminance at an arbitrary coordinate point in the island. As described above, the center-of-gravity coordinates of the toner particles of the present invention and the center-of-gravity coordinates of each island present in the toner particles are calculated based on the luminance at each arbitrary point, that is, from the brightness of the image.
[0155]
In the present invention, the average value of the area of the Voronoi polygon formed by the perpendicular bisector between the centroids of adjacent islands in the toner particles is 20,000 to 120,000 nm.²It is preferable that the coefficient of variation of the average value of the area is 25% or less. In the present invention, the coefficient of variation of the area of the Voronoi polygon is calculated by the following equation.
[0156]
The coefficient of variation of the area of the Voronoi polygon = {S4 / K4} × 100 (%)
In the formula, S4 represents the standard deviation of the area of the Voronoi polygon in the island portion present in the toner particles, and K4 represents the average value of the area of the Voronoi polygon.
[0157]
Further, the average value of Voronoi polygons of adjacent islands in the toner particles according to the present invention is more preferably 40,000 to 100,000 nm.²And the coefficient of variation is 20% or less.
[0158]
The average value of the area of the Voronoi polygon formed by the perpendicular bisector between the centroids of adjacent islands in the toner particles according to the present invention is 20,000 to 120,000 nm.²However, if it is out of this range, the occupancy of the islands in the toner particles becomes unfavorable. For example, a colorant present as an island in the particles is effective in the toner particles. This is not preferable because it is difficult to find the effect of the present invention.
[0159]
The variation coefficient of the average value of the area of the Voronoi polygon formed from the adjacent islands in the toner particles according to the present invention is to specify the variation in the area of the Voronoi polygon, that is, the island portion in the toner particles The variation of the occupied state is specified, and the variation coefficient of the average value of the area of the Voronoi polygon is preferably 25% or less, more preferably 20% or less. When the coefficient of variation is 0%, that is, in a state where there is no variation in the average value of the Voronoi polygon area, in other words, in a state where there is no variation in the occupied state of the islands in the toner particles, all the toner particles There is no need for the occupancy to be the same.
[0160]
In the present invention, the area of the Voronoi polygon formed by the islands existing within the specific range from the center of gravity of the toner particles is smaller than the area of the Voronoi polygon formed by the islands existing outside the range. Preferably there is. That is, in the present invention, the average value of the areas of Voronoi polygons formed by islands existing within a radius of 1000 nm from the gravity center of the toner particles is the average value of the areas of Voronoi polygons formed by islands existing within a radius of 1000 nm. This means that in the toner particles, it is preferable that the dispersed state of the islands is sparse at some distance from the center of gravity of the toner particles. By satisfying this condition, in the toner according to the present invention, the effects achieved by the present invention can be more effectively obtained by appropriately dispersing the islands in the toner particles.
[0161]
Further, in the present invention, the islands are appropriately dispersed, the islands are appropriately spaced from each other, the islands are not unevenly distributed in the toner particles, and the colorant is effectively added to the toner particles. Polygon area is 160,000nm²It is preferable that 5 to 30 islands exist in one toner particle.
[0162]
(Molecular weight distribution of resin particles and toner)
The toner of the present invention preferably has a molecular weight distribution peak or shoulder at 100,000 to 1,000,000 and 1,000 to 50,000, and further has a molecular weight distribution peak or shoulder of 100. It is preferable that it exists in 1,000-1,000,000, 25,000-150,000, and 1,000-50,000.
[0163]
The molecular weight of the resin particles is both a high molecular weight component having a peak or shoulder in the region of 100,000 to 1,000,000 and a low molecular weight component having a peak or shoulder in the region of 1,000 to less than 50,000. Is preferable, and it is more preferable to use an intermediate molecular weight resin having a peak or shoulder at a portion of 15,000 to 100,000.
[0164]
As a method for measuring the molecular weight of the toner or resin described above, GPC (gel permeation chromatography) using THF (tetrahydrofuran) as a solvent is preferable. That is, 1.0 ml of THF is added to 0.5 to 5 mg of a measurement sample, more specifically 1 mg, and the mixture is sufficiently dissolved by stirring at room temperature using a magnetic stirrer or the like. Subsequently, after processing with a membrane filter having a pore size of 0.45 to 0.50 μm, the solution is injected into GPC. The measurement conditions of GPC are measured by stabilizing the column at 40 ° C., flowing THF at a flow rate of 1.0 ml / min, and injecting about 100 μl of a sample having a concentration of 1 mg / ml. The column is preferably used in combination with a commercially available polystyrene gel column. For example, Shodex GPC KF-801, 802, 803, 804, 805, 806, 807 made by Showa Denko KK, TSKgel G1000H, G2000H, G3000H, G4000H, G5000H, G6000H, G7000H, TSK guard column manufactured by Tosoh Corporation Combinations can be mentioned. As a detector, a refractive index detector (IR detector) or a UV detector may be used. In the measurement of the molecular weight of a sample, the molecular weight distribution of the sample is calculated using a calibration curve created using monodisperse polystyrene standard particles. About 10 points may be used as polystyrene for preparing a calibration curve.
[0165]
(Developer)
The toner of the present invention may be used as a one-component developer or a two-component developer, but is particularly preferably used as a non-magnetic one-component developer.
[0166]
When the toner of the present invention contains a fluorine atom as the component a, a peak is present at 689.0 to 692.0 eV in measurement by X-ray photoelectron spectroscopy (referred to as ESCA or XPS) in order to sufficiently bring out the effects of the present invention. Furthermore, it is preferable that the ratio of the number of fluorine atoms and the number of carbon atoms calculated from the peak intensity is 0.001 to 0.004. Particularly preferably, a peak exists at 690.5 to 691.0 eV, and the ratio of the number of fluorine atoms to the number of carbon atoms calculated from the peak intensity is 0.001 to 0.002.
[0167]
Further, the toner of the present invention exhibits a high fixability and contains a crystalline compound in order to avoid the offset phenomenon as described in JP-A-8-328295, and is attributed to the crystalline compound. It is preferable that at least one endothermic peak in the differential thermal analysis is present at 60 to 120 ° C., and the endothermic amount is 4 J to 30 J / g.
[0168]
Next, a method for producing the toner of the present invention will be described.
The toner of the present invention is obtained by polymerizing at least a polymerizable monomer in an aqueous medium. In this production method, resin particles are prepared by polymerizing a polymerizable monomer by a suspension polymerization method. Alternatively, the emulsion resin of the required additives is added (in an aqueous medium), and the monomer is emulsion polymerized or miniemulsion polymerized to prepare fine resin particles, and charged as necessary. After adding the controllable resin particles, an organic solvent, an aggregating agent such as a salt, and the like are added to produce the resin particles by agglomeration and fusion.
[0169]
《Shape and manufacturing method》
<Emulsion polymerization method>
Further, as a method for producing the toner of the present invention, a method in which resin particles are prepared by salting out / fusion in an aqueous medium can also be mentioned. The method is not particularly limited, and examples thereof include methods disclosed in JP-A-5-265252, JP-A-6-329947, and JP-A-9-15904. That is, a method of salting out, agglomerating, and fusing a plurality of fine particles composed of resin particles and colorants, or a constituent material such as resin particles and a colorant, and in particular using an emulsifier in water Then, a coagulant with a critical coagulation concentration or higher is added for salting out, and at the same time, the formed polymer is heated and fused at a temperature higher than the glass transition temperature of the polymer itself to gradually grow the particle size while forming fused particles. When the desired particle size is reached, a large amount of water is added to stop particle size growth, and the shape is controlled by smoothing the particle surface while heating and stirring, and the particles are heated in a fluidized state while containing water. By drying, the toner of the present invention can be formed. Here, a solvent that is infinitely soluble in water, such as alcohol, may be added simultaneously with the flocculant.
[0170]
In the method for producing a toner of the present invention, the composite resin fine particles and the colorant particles formed through the step of polymerizing the polymerizable monomer after at least dissolving the crystalline substance in the polymerizable monomer are salted out / It is obtained by fusing. The toner of the present invention dissolves a crystalline substance in a polymerizable monomer, but it may be dissolved and dissolved or melted and dissolved.
[0171]
The toner production method of the present invention is to salt out / fuse the composite resin fine particles obtained by the multistage polymerization method and the colorant particles. The multistage polymerization method will be described below.
[0172]
<< Method for producing composite resin particles obtained by multistage polymerization process >>
The toner manufacturing method of the present invention comprises the following steps.
[0173]
1: multistage polymerization process,
2: a salting-out / fusion process in which toner particles are obtained by salting-out / fusion of composite resin particles and colorant particles;
3: A filtration / washing step of filtering out the toner particles from the dispersion system of the toner particles and removing the surfactant from the toner particles;
4: a drying process for drying the washed toner particles;
5: Step of adding an external additive to the dried toner particles
Consists of
[0174]
Hereinafter, each step will be described in detail.
[Multistage polymerization process]
The multi-stage polymerization step is a polymerization method performed for expanding the molecular weight distribution of the resin particles so as to obtain a toner in which offset generation is prevented. That is, in order to form phases having different molecular weight distribution in one resin particle, the polymerization reaction is performed in multiple stages, and the obtained resin particle has a molecular weight gradient from the center of the particle toward the surface layer. It is intended to be formed. For example, a method of forming a low molecular weight surface layer by first obtaining a high molecular weight resin particle dispersion and then newly adding a polymerizable monomer and a chain transfer agent is employed.
[0175]
In the present invention, it is preferable to employ a multi-stage polymerization method of three-stage polymerization or more from the viewpoint of production stability and crushing strength of the resulting toner. Hereinafter, the two-stage polymerization method and the three-stage polymerization method, which are representative examples of the multistage polymerization method, will be described. The toner obtained by such a multistage polymerization reaction preferably has a lower molecular weight as the surface layer from the viewpoint of crushing strength.
[0176]
<Two-stage polymerization method>
The two-stage polymerization method is a method for producing composite resin particles composed of a central portion (core) formed from a high molecular weight resin containing a crystalline substance and an outer layer (shell) formed from a low molecular weight resin. is there.
[0177]
This method will be described in detail. First, a crystalline substance is dissolved in a monomer to prepare a monomer solution, and the monomer solution is added to oil droplets in an aqueous medium (for example, a surfactant aqueous solution). After the dispersion, this system is polymerized (first stage polymerization) to prepare a dispersion of high molecular weight resin particles containing a crystalline substance.
[0178]
Next, a polymerization initiator and a monomer for obtaining a low molecular weight resin are added to the dispersion of the resin particles, and the monomer is polymerized in the presence of the resin particles (second-stage polymerization). Thus, a coating layer made of a low molecular weight resin (monomer polymer) is formed on the surface of the resin particles.
[0179]
<Three-stage polymerization method>
The three-stage polymerization method produces composite resin particles composed of a central part (core) formed from a high molecular weight resin, an intermediate layer containing a crystalline substance, and an outer layer (shell) formed from a low molecular weight resin. Is the method. The toner of the present invention exists as the composite resin particles as described above.
[0180]
This method will be specifically described. First, a dispersion of resin particles obtained by a polymerization process (first-stage polymerization) according to a conventional method is added to an aqueous medium (for example, an aqueous solution of a surfactant). In the aqueous medium, a monomer solution obtained by dissolving a crystalline substance in a monomer is dispersed in oil droplets, and then this system is polymerized (second-stage polymerization) to obtain resin particles (cores). A coating layer (intermediate layer) made of a resin (monomer polymer) containing a crystalline substance is formed on the surface of the particles, and a dispersion of composite resin particles (high molecular weight resin / intermediate molecular weight resin) is formed. Prepare.
[0181]
Next, a polymerization initiator and a monomer for obtaining a low molecular weight resin are added to the obtained dispersion of composite resin particles, and the monomer is polymerized in the presence of the composite resin particles (third-stage polymerization). ), A coating layer made of a low molecular weight resin (monomer polymer) is formed on the surface of the composite resin particles. In the above method, the incorporation of the intermediate layer is preferable because the crystalline substance can be finely and uniformly dispersed.
[0182]
One feature of the toner production method according to the present invention is that the polymerizable monomer is polymerized in an aqueous medium. That is, when forming resin particles (core particles) or a coating layer (intermediate layer) containing a crystalline substance, the crystalline substance is dissolved in the monomer, and the resulting monomer solution is oiled in an aqueous medium. It is a method of obtaining latex particles by dispersing in drops and adding a polymerization initiator to this system for polymerization treatment.
[0183]
The aqueous medium as used in the field of this invention means the medium which consists of 50-100 mass% of water and 0-50 mass% of water-soluble organic solvents. Examples of the water-soluble organic solvent include methanol, ethanol, isopropanol, butanol, acetone, methyl ethyl ketone, tetrahydrofuran, and the like, and an alcohol-based organic solvent that does not dissolve the obtained resin is preferable.
[0184]
As a suitable polymerization method for forming resin particles or a coating layer containing a crystalline substance, the crystalline substance is a monomer in an aqueous medium in which a surfactant having a concentration equal to or lower than the critical micelle concentration is dissolved. The monomer solution dissolved in is dispersed in oil droplets using mechanical energy to prepare a dispersion, and a water-soluble polymerization initiator is added to the resulting dispersion to cause radical polymerization in the oil droplets. A method (hereinafter referred to as “mini-emulsion method” in the present invention), and the effects of the present invention can be exhibited more preferably. In the above method, an oil-soluble polymerization initiator may be used instead of or together with the water-soluble polymerization initiator.
[0185]
According to the mini-emulsion method that mechanically forms oil droplets, unlike the usual emulsion polymerization method, the crystalline substance dissolved in the oil phase has little detachment and is sufficient in the formed resin particles or coating layer. Any amount of crystalline material can be introduced.
[0186]
Here, the disperser for dispersing oil droplets by mechanical energy is not particularly limited. For example, the stirring device “CLEARMIX” (M technique (M Co., Ltd.), ultrasonic disperser, mechanical homogenizer, manton gorin, pressure homogenizer, and the like. The dispersed particle diameter is 10 nm to 1000 nm, preferably 50 nm to 1000 nm, and more preferably 30 nm to 300 nm. Here, by giving a distribution to the dispersed particle diameter, the phase separation structure of the crystalline substance in the toner particles, that is, the ferret diameter, the shape factor, and the coefficient of variation thereof may be controlled.
[0187]
In addition, as other polymerization methods for forming resin particles or a coating layer containing a crystalline substance, known methods such as an emulsion polymerization method, a suspension polymerization method, and a seed polymerization method can be employed. These polymerization methods can also be employed to obtain resin particles (core particles) or coating layers constituting the composite resin particles that do not contain a crystalline substance.
[0188]
The particle diameter of the composite resin particles obtained in this polymerization step is in the range of 10 nm to 1000 nm in terms of mass average particle diameter measured using an electrophoretic light scattering photometer “ELS-800” (manufactured by Otsuka Electronics Co., Ltd.). Is preferred.
[0189]
Moreover, it is preferable that the glass transition temperature (Tg) of a composite resin particle exists in the range of 48-74 degreeC, More preferably, it is 52-64 degreeC. The softening point of the composite resin particles is preferably in the range of 95 to 140 ° C.
[0190]
The toner of the present invention is obtained by forming a resin layer formed by fusing resin particles on the surface of the resin and colored particles by a salting-out / fusing method. This will be described below.
[0191]
[Salting out / fusion process]
This salting-out / fusion step is carried out by salting out / bonding the composite resin particles and the colorant particles obtained in the multi-stage polymerization step (to cause salting-out and fusion at the same time) to form an irregular shape ( This is a step of obtaining non-spherical toner particles.
[0192]
In the present invention, salting out / fusion means that salting out (aggregation of particles) and fusion (disappearance of the interface between particles) occur simultaneously, or act of causing salting out and fusion at the same time. . In order to perform salting-out and fusion at the same time, it is necessary to agglomerate particles (composite resin particles, colorant particles) under a temperature condition higher than the glass transition temperature (Tg) of the resin constituting the composite resin particles. .
[0193]
In this salting-out / fusion process, internal additive particles such as charge control agents (fine particles having a number average primary particle size of about 10 to 1000 nm) may be salted out / fused together with the composite resin particles and the colorant particles. Good. The colorant particles may be surface-modified, and conventionally known ones can be used as the surface modifier.
[0194]
[Aging process]
The aging step is a step subsequent to the salting-out / fusion step, and after the resin particles are fused, the temperature is kept near the melting point of the crystalline substance, preferably the melting point ± 20 ° C., and stirring is continued at a constant strength. This is a step of phase-separating the crystalline substance. In this step, it is possible to control the ferret diameter, shape factor, and variation coefficient of the crystalline substance.
[0195]
The colorant particles are subjected to a salting out / fusion process in a state of being dispersed in an aqueous medium. The aqueous medium in which the colorant particles are dispersed is preferably an aqueous solution in which the surfactant is dissolved at a concentration equal to or higher than the critical micelle concentration (CMC).
[0196]
The disperser used for the dispersion treatment of the colorant particles is not particularly limited, but preferably a stirring device “CLEARMIX” (manufactured by M Technique Co., Ltd.) equipped with a rotor rotating at high speed, ultrasonic dispersion And pressure dispersers such as a mechanical homogenizer, manton gourin, and pressure homogenizer, and medium dispersers such as a Getzman mill and a diamond fine mill.
[0197]
In order to salt out / fuse the composite resin particles and the colorant particles, a salting-out agent (flocculating agent) having a critical aggregation concentration or more is added to the dispersion in which the composite resin particles and the colorant particles are dispersed. In addition, it is necessary to heat the dispersion to a temperature higher than the glass transition temperature (Tg) of the composite resin particles.
[0198]
The temperature range suitable for salting out / fusion is (Tg + 10) to (Tg + 50 ° C.), particularly preferably (Tg + 15) to (Tg + 40 ° C.). In addition, an organic solvent that is infinitely soluble in water may be added in order to effectively perform fusion.
[0199]
In the present invention, resin particles and a colorant are salted out, aggregated, and fused in an aqueous medium to obtain colored particles (referred to as toner particles in the present invention), and then the toner particles are separated from the aqueous medium. When performing, it is preferable to carry out at the temperature more than the craft point of the surfactant which exists in an aqueous medium, More preferably, it is preferable to carry out in the temperature range of a craft point-(craft point +20 degreeC).
[0200]
The Kraft point is a temperature at which an aqueous solution containing a surfactant starts to become cloudy, and the Kraft point is measured as follows.
[0201]
<Measurement of craft point>
A solution was prepared by adding the actual amount of the flocculant to the aqueous medium, that is, the surfactant solution used in the salting out, agglomeration and fusion processes, and this solution was stored at 1 ° C. for 5 days. The solution was then gradually heated with stirring until clear. The temperature at which the solution becomes clear is defined as the Kraft point.
[0202]
The toner for developing an electrostatic charge image of the present invention is described above in order to stabilize and maintain the chargeability particularly with respect to the environment from the viewpoint of suppressing excessive charge to the toner particles and imparting uniform chargeability. It is preferable to contain 250 to 20000 ppm, more preferably 800 to 5000 ppm in the toner.
[0203]
Moreover, in this invention, it is preferable that the total value of the bivalent (trivalent) metal element used for a coagulant | flocculant and the monovalent | monohydric metal element added as an aggregation terminator mentioned later is 350-35000 ppm. The residual amount of metal ions in the toner can be measured by using a fluorescent X-ray analyzer “System 3270” (manufactured by Rigaku Denki Kogyo Co., Ltd.) and using a metal species of a metal salt used as a flocculant (for example, calcium chloride). It can be determined by measuring the intensity of the fluorescent X-ray emitted from the derived calcium or the like. As a specific measurement method, a plurality of toners having a known content ratio of the flocculant metal salt are prepared, each toner 5g is pelletized, the content ratio (mass ppm) of the flocculant metal salt, and the metal type of the metal salt The relationship (calibration curve) with the fluorescent X-ray intensity (peak intensity) is measured. Next, the toner (sample) whose content of the flocculant metal salt is to be measured is similarly pelletized, and the fluorescent X-ray intensity from the metal species of the flocculant metal salt is measured. Amount "can be determined.
[0204]
[Filtering and washing process]
In this filtration / washing step, a filtration treatment for filtering the toner particles from the toner particle dispersion obtained in the above step, and a surfactant or salt from the filtered toner particles (cake-like aggregate). A cleaning process for removing deposits such as a depositing agent is performed. Here, the filtration method is not particularly limited, such as a centrifugal separation method, a vacuum filtration method using Nutsche or the like, a filtration method using a filter press or the like.
[0205]
[Drying process]
This step is a step of drying the washed toner particles.
[0206]
Examples of dryers used in this process include spray dryers, vacuum freeze dryers, vacuum dryers, etc., stationary shelf dryers, mobile shelf dryers, fluidized bed dryers, rotary dryers It is preferable to use a stirring dryer or the like.
[0207]
The water content of the dried toner particles is preferably 5% by mass or less, and more preferably 2% by mass or less. In addition, when the toner particles that have been dried are aggregated due to weak interparticle attraction, the aggregate may be crushed. Here, as the crushing treatment apparatus, a mechanical crushing apparatus such as a jet mill, a Henschel mixer, a coffee mill, or a food processor can be used.
[0208]
The toner of the present invention forms composite resin particles in the absence of a colorant, adds a dispersion of the colorant particles to the dispersion of the composite resin particles, and saltes out the composite resin particles and the colorant particles. It is preferably prepared by fusing.
[0209]
Thus, the polymerization reaction for obtaining the composite resin particles is not inhibited by preparing the composite resin particles in a system in which no colorant is present. Therefore, according to the toner of the present invention, the excellent offset resistance is not impaired, and the fixing device is not contaminated or the image is not stained due to the accumulation of toner.
[0210]
In addition, as a result of the polymerization reaction for obtaining the composite resin particles being reliably performed, no monomer or oligomer remains in the obtained toner particles, and the heat fixing step of the image forming method using the toner In this case, no off-flavor is generated.
[0211]
Further, since the surface characteristics of the obtained toner particles are uniform and the charge amount distribution is sharp, an image having excellent sharpness can be formed over a long period of time. According to such a toner having a uniform composition, molecular weight, and surface characteristics between toner particles, an image forming method including a fixing process using a contact heating method maintains good adhesion (high fixing strength) to an image support. However, it is possible to improve the anti-offset property and the anti-winding property, and an image having an appropriate gloss can be obtained.
[0212]
Next, each component used in the toner manufacturing process will be described in detail.
(Polymerizable monomer)
As a polymerizable monomer for producing the resin (binder) used in the present invention, a hydrophobic monomer is an essential constituent, and a crosslinkable monomer is used as necessary. Further, it is desirable to contain at least one monomer having an acidic polar group or a monomer having a basic polar group in the structure as described below.
[0213]
(1) Hydrophobic monomer
The hydrophobic monomer constituting the monomer component is not particularly limited, and conventionally known monomers can be used. Moreover, it can be used combining 1 type (s) or 2 or more types so that the required characteristic may be satisfy | filled.
[0214]
Specifically, monovinyl aromatic monomers, (meth) acrylic acid ester monomers, vinyl ester monomers, vinyl ether monomers, monoolefin monomers, diolefin monomers , Halogenated olefin monomers and the like can be used.
[0215]
Examples of vinyl aromatic monomers include styrene, o-methyl styrene, m-methyl styrene, p-methyl styrene, p-methoxy styrene, p-phenyl styrene, p-chloro styrene, p-ethyl styrene, p. -N-butyl styrene, p-tert-butyl styrene, pn-hexyl styrene, pn-octyl styrene, pn-nonyl styrene, pn-decyl styrene, pn-dodecyl styrene, 2, Examples thereof include styrene monomers such as 4-dimethylstyrene and 3,4-dichlorostyrene and derivatives thereof.
[0216]
Examples of (meth) acrylic acid ester monomers include acrylic acid, methacrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, phenyl acrylate, methyl methacrylate, Examples include ethyl methacrylate, butyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, ethyl β-hydroxyacrylate, propyl γ-aminoacrylate, stearyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, etc. It is done.
[0217]
Examples of vinyl ester monomers include vinyl acetate, vinyl propionate, vinyl benzoate, and examples of vinyl ether monomers include vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether, vinyl phenyl ether, and the like. It is done.
[0218]
Examples of the monoolefin monomer include ethylene, propylene, isobutylene, 1-butene, 1-pentene, 4-methyl-1-pentene, and the diolefin monomer includes butadiene, isoprene, Examples include chloroprene.
[0219]
(2) Crosslinkable monomer
In order to improve the characteristics of the resin particles, a crosslinkable monomer may be added. Examples of the crosslinkable monomer include those having two or more unsaturated bonds such as divinylbenzene, divinylnaphthalene, divinyl ether, diethylene glycol methacrylate, ethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, and diallyl phthalate.
[0220]
(3) Monomers having acidic polar groups
Examples of the monomer having an acidic polar group include (a) an α, β-ethylenically unsaturated compound having a carboxyl group and (b) an α, β-ethylenically unsaturated compound having a sulfonic acid group. Can do.
[0221]
Examples of α, β-ethylenically unsaturated compounds having a carboxyl group include acrylic acid, methacrylic acid, fumaric acid, maleic acid, itaconic acid, cinnamic acid, maleic acid monobutyl ester, maleic acid monooctyl ester, And metal salts such as Na and Zn.
[0222]
Examples of the α, β-ethylenically unsaturated compound having a sulfonic acid group include sulfonated styrene and its Na salt, allylsulfosuccinic acid, octyl allylsulfosuccinate, and Na salts thereof.
[0223]
(4) Monomers having basic polar groups
As the monomer having a basic polar group, (i) a (meth) acrylic acid ester of an aliphatic alcohol having 1 to 12, preferably 2 to 8 and particularly preferably 2 having an amine group or a quaternary ammonium group. , (Ii) (meth) acrylic acid amide or (meth) acrylic acid amide mono- or disubstituted with an alkyl group having 1 to 18 carbon atoms optionally on N, (iii) a heterocyclic ring having N as a ring member Examples thereof include vinyl compounds substituted with a group and (iv) N, N-diallyl-alkylamine or a quaternary ammonium salt thereof. Of these, (meth) acrylic acid esters of aliphatic alcohols having an amine group or quaternary ammonium group (i) are preferred as monomers having a basic polar group.
[0224]
Examples of (meth) acrylic acid esters of aliphatic alcohols having an amine group or quaternary ammonium group (i) include dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, diethylaminoethyl acrylate, diethylaminoethyl methacrylate, and the above four compounds. A quaternary ammonium salt, 3-dimethylaminophenyl acrylate, 2-hydroxy-3-methacryloxypropyltrimethylammonium salt, etc. can be mentioned.
[0225]
Examples of (ii) (meth) acrylic acid amide or mono- or dialkyl-substituted (meth) acrylic acid amide include acrylamide, N-butylacrylamide, N, N-dibutylacrylamide, piperidylacrylamide, methacrylamide, and N-butylmethacrylate. Examples thereof include amide, N, N-dimethylacrylamide, N-octadecylacrylamide and the like.
[0226]
Examples of the vinyl compound substituted with a heterocyclic group having N as a ring member in (iii) include vinylpyridine, vinylpyrrolidone, vinyl-N-methylpyridinium chloride, vinyl-N-ethylpyridinium chloride and the like.
[0227]
Examples of (iv) N, N-diallyl-alkylamine include N, N-diallylmethylammonium chloride and N, N-diallylethylammonium chloride.
[0228]
(Chain transfer agent)
A known chain transfer agent can be used for the purpose of adjusting the molecular weight. Although it does not specifically limit as a chain transfer agent, For example, the compound which has mercapto groups, such as an octyl mercaptan, a dodecyl mercaptan, a tert- dodecyl mercaptan, is used. In particular, a compound having a mercapto group is preferably used because it suppresses odor during heat-fixing, gives a toner having a sharp molecular weight distribution, and is excellent in storage stability, fixing strength, and offset resistance. Preferred examples include ethyl thioglycolate, propyl thioglycolate, propyl thioglycolate, butyl thioglycolate, t-butyl thioglycolate, 2-ethylhexyl thioglycolate, octyl thioglycolate, decyl thioglycolate , A compound having a mercapto group of ethylene glycol, a compound having a mercapto group of neopentyl glycol, and a compound having a mercapto group of pentaerythritol. Among these, n-octyl-3-mercaptopropionic acid ester is particularly preferable from the viewpoint of suppressing odor during toner heat fixing.
[0229]
(Surfactant)
In particular, in order to perform miniemulsion polymerization using the above-described polymerizable monomer, it is preferable to disperse oil droplets in an aqueous medium using a surfactant. The surfactant that can be used in this case is not particularly limited, and the following ionic surfactants can be given as examples of suitable compounds.
[0230]
Examples of the ionic surfactant include sulfonates (sodium dodecylbenzenesulfonate, sodium arylalkylpolyethersulfonate, 3,3-disulfonediphenylurea-4,4-diazo-bis-amino-8-naphthol- 6-sulfonate sodium, ortho-carboxybenzene-azo-dimethylaniline, 2,2,5,5-tetramethyl-triphenylmethane-4,4-diazo-bis-β-naphthol-6-sulfonate sodium, etc.) , Sulfate esters (sodium dodecyl sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, etc.), fatty acid salts (sodium oleate, sodium laurate, sodium caprate, sodium caprylate, sodium caproate, steari Potassium, calcium oleate and the like).
[0231]
In the present invention, surfactants represented by the following general formulas (A) and (B) are particularly preferably used.
Formula (A) R₁(OR₂)_nOSO_ThreeM
Formula (B) R₁(OR₂)_nSO_ThreeM
Where R₁Represents an alkyl group or arylalkyl group having 6 to 22 carbon atoms, preferably an alkyl group or arylalkyl group having 8 to 20 carbon atoms, more preferably an alkyl group or arylalkyl group having 9 to 16 carbon atoms. is there.
[0232]
R₁Examples of the alkyl group having 6 to 22 carbon atoms represented by: n-hexyl group, n-heptyl group, n-octyl group, n-decyl group, n-undecyl group, n-hexadecyl group, cyclopropyl group , A cyclopentyl group, a cyclohexyl group, and the like, and examples of the arylalkyl group represented by R1 include a benzyl group, a diphenylmethyl group, a cinnamyl group, a styryl group, a trityl group, and a phenethyl group.
[0233]
In the general formulas (1) and (2), R₂Represents an alkylene group having 2 to 6 carbon atoms, preferably an alkylene group having 2 to 3 carbon atoms. R₂Examples of the alkylene group having 2 to 6 carbon atoms represented by: ethylene group, trimethylene group, tetramethylene group, propylene group, ethylethylene group and the like.
[0234]
In general formula (1), (2), n is an integer of 1-11, Preferably it is 2-10, More preferably, it is 2-5, Most preferably, it is 2-3. Examples of the monovalent metal element represented by M include sodium, potassium, and lithium. Of these, sodium is preferably used.
[0235]
Specific examples of the surfactants represented by the general formulas (1) and (2) are shown below, but the present invention is not limited thereto.
[0236]
Compound (101): C_TenH_{twenty one}(OCH₂CH₂)₂OSO_ThreeNa
Compound (102): C_TenH_{twenty one}(OCH₂CH₂)_ThreeOSO_ThreeNa
Compound (103): C_TenH_{twenty one}(OCH₂CH₂)₂SO_ThreeNa
Compound (104): C_TenH_{twenty one}(OCH₂CH₂)_ThreeSO_ThreeNa
Compound (105): C₈H₁₇(OCH₂CH (CH_Three))₂OSO_ThreeNa
Compound (106): C₁₈H₃₇(OCH₂CH₂)₂OSO_ThreeNa
In the present invention, from the viewpoint of maintaining the charge holding function of the toner in a good state, suppressing fog generation under high temperature and high humidity, and improving transferability, and suppressing the increase in charge amount under low temperature and low humidity, From the viewpoint of stabilizing the amount, the content of the surfactant represented by the general formulas (1) and (2) in the toner for developing an electrostatic charge image is preferably 1 to 1000 ppm, more preferably 5 It is -500 ppm, Most preferably, it is 7-100 ppm.
[0237]
In the present invention, by setting the amount of the surfactant to be contained in the toner within the above described range, the chargeability of the electrostatic image developing toner of the present invention is always uniform without being influenced by environmental influences. It can be applied and maintained in a stable state.
[0238]
Further, the content of the surfactant represented by the above general formulas (1) and (2) contained in the toner for developing an electrostatic charge image of the present invention is calculated by the following method.
[0239]
1 g of toner is dissolved in 50 ml of chloroform, and the surfactant is extracted from the chloroform layer with 100 ml of ion exchange water. Further, the extracted chloroform layer is extracted once again with 100 ml of ion-exchanged water to obtain a total of 200 ml of extract (water layer), and this extract is diluted to 500 ml.
[0240]
Using this diluted solution as a test solution, in accordance with the method defined in JIS 33636, color was developed with methylene blue, the absorbance was measured, and the surfactant content in the toner was measured from a separately prepared calibration curve. is there.
[0241]
Moreover, the structure of the surfactant represented by the general formulas (1) and (2)¹The structure was analyzed by H-NMR.
[0242]
In the present invention, a metal salt can be preferably used as an aggregating agent in a step of salting out, agglomerating, and fusing resin particles from a dispersion of resin particles prepared in an aqueous medium. More preferably, a metal salt is used as the flocculant. The reason is that a divalent or trivalent metal salt is preferable to a monovalent metal salt because the critical aggregation concentration (coagulation value or coagulation point) is smaller.
[0243]
In the present invention, a nonionic surfactant can also be used. Specifically, polyethylene oxide, polypropylene oxide, a combination of polypropylene oxide and polyethylene oxide, ester of polyethylene glycol and higher fatty acid, alkylphenol polyethylene oxide, Examples include higher fatty acid and polyethylene glycol esters, higher fatty acid and polypropylene oxide esters, and sorbitan esters.
[0244]
In the present invention, these surfactants are mainly used as an emulsifier during emulsion polymerization, but may be used for other steps or for other purposes.
[0245]
(Flocculant)
In the present invention, a metal salt can be preferably used as an aggregating agent in a step of salting out, agglomerating, and fusing resin particles from a dispersion of resin particles prepared in an aqueous medium. More preferably, a metal salt is used as the flocculant. The reason is that a divalent or trivalent metal salt is preferable to a monovalent metal salt because the critical aggregation concentration (coagulation value or coagulation point) is smaller.
[0246]
The flocculant used in the present invention is a monovalent metal salt which is a salt of an alkali metal such as sodium, potassium or lithium, for example, a salt of an alkaline earth metal such as calcium or magnesium, or a divalent such as manganese or copper. Examples thereof include metal salts and trivalent metal salts such as iron and aluminum.
[0247]
Specific examples of these metal salts are shown below. Examples of the monovalent metal salt include sodium chloride, potassium chloride, lithium chloride, and examples of the divalent metal salt include calcium chloride, zinc chloride, copper sulfate, magnesium sulfate, manganese sulfate, and the like. Examples thereof include aluminum chloride and iron chloride. These are appropriately selected according to the purpose, but divalent or trivalent metal salts having a small critical aggregation concentration are preferable.
[0248]
The critical flocculation concentration referred to in the present invention is an index relating to the stability of the dispersion in the aqueous dispersion, and indicates the concentration of the flocculating agent added when the flocculating agent is added. This critical coagulation concentration varies greatly depending on the latex itself and the dispersant. For example, it is described in Seizo Okamura et al., Polymer Chemistry 17,601 (1960), etc., and the value can be known by following these descriptions. As another method, a desired salt is added to the target particle dispersion at a different concentration, the ζ potential of the dispersion is measured, and the salt concentration at the point where the ζ potential begins to change is defined as the critical aggregation concentration. It is also possible to do.
[0249]
In the present invention, the polymer fine particle dispersion is treated with a metal salt so as to have a concentration equal to or higher than the critical aggregation concentration. At this time, as a matter of course, whether the metal salt is added directly or as an aqueous solution is arbitrarily selected according to the purpose. When added as an aqueous solution, the added metal salt must be equal to or higher than the critical aggregation concentration of the polymer particles with respect to the volume of the polymer particle dispersion and the total volume of the metal salt aqueous solution.
[0250]
In the present invention, the metal salt concentration may be not less than the critical aggregation concentration, but is preferably 1.2 times or more, more preferably 1.5 times or more the critical aggregation concentration.
[0251]
(Coloring agent)
The toner of the present invention is obtained by salting out / fusion-bonding the composite resin particles and the colorant particles. Examples of the colorant constituting the toner of the present invention (colorant particles used for salting out / fusion with composite resin particles) include various inorganic pigments, organic pigments, and dyes. A conventionally well-known thing can be used as an inorganic pigment. Specific inorganic pigments are exemplified below.
[0252]
Examples of the black pigment include carbon black such as furnace black, channel black, acetylene black, thermal black, and lamp black, and magnetic powder such as magnetite and ferrite.
[0253]
These inorganic pigments can be used alone or in combination as required. Moreover, the addition amount of a pigment is 2-20 mass% with respect to a polymer, Preferably 3-15 mass% is selected.
[0254]
When used as a magnetic toner, the above-mentioned magnetite can be added. In this case, it is preferable to add 20 to 60% by mass in the toner from the viewpoint of imparting predetermined magnetic properties.
[0255]
Conventionally known organic pigments and dyes can also be used, and specific organic pigments and dyes are exemplified below.
[0256]
Examples of the magenta or red pigment include C.I. I. Pigment red 2, C.I. I. Pigment red 3, C.I. I. Pigment red 5, C.I. I. Pigment red 6, C.I. I. Pigment red 7, C.I. I. Pigment red 15, C.I. I. Pigment red 16, C.I. I. Pigment red 48: 1, C.I. I. Pigment red 53: 1, C.I. I. Pigment red 57: 1, C.I. I. Pigment red 122, C.I. I. Pigment red 123, C.I. I. Pigment red 139, C.I. I. Pigment red 144, C.I. I. Pigment red 149, C.I. I. Pigment red 166, C.I. I. Pigment red 177, C.I. I. Pigment red 178, C.I. I. And CI Pigment Red 222.
[0257]
Examples of the pigment for orange or yellow include C.I. I. Pigment orange 31, C.I. I. Pigment orange 43, C.I. I. Pigment yellow 12, C.I. I. Pigment yellow 13, C.I. I. Pigment yellow 14, C.I. I. Pigment yellow 15, C.I. I. Pigment yellow 17, C.I. I. Pigment yellow 93, C.I. I. Pigment yellow 94, C.I. I. Pigment yellow 138, C.I. I. Pigment yellow 180, C.I. I. Pigment yellow 185, C.I. I. Pigment yellow 155, C.I. I. And CI Pigment Yellow 156.
[0258]
Examples of the pigment for green or cyan include C.I. I. Pigment blue 15, C.I. I. Pigment blue 15: 2, C.I. I. Pigment blue 15: 3, C.I. I. Pigment blue 16, C.I. I. Pigment blue 60, C.I. I. And CI Pigment Green 7.
[0259]
Examples of the dye include C.I. I. Solvent Red 1, 49, 52, 58, 63, 111, 122, C.I. I. Solvent Yellow 19, 44, 77, 79, 81, 82, 93, 98, 103, 104, 112, 162, C.I. I. Solvent Blue 25, 36, 60, 70, 93, 95, etc. can be used, and mixtures thereof can also be used.
[0260]
These organic pigments and dyes can be used alone or in combination as required. Moreover, the addition amount of a pigment is 2-20 mass% with respect to a polymer, Preferably it is 3-15 mass%.
[0261]
The colorant (colorant particles) constituting the toner of the present invention may be surface-modified. A conventionally well-known thing can be used as a surface modifier, Specifically, a silane coupling agent, a titanium coupling agent, an aluminum coupling agent etc. can be used preferably. Examples of the silane coupling agent include alkoxysilanes such as methyltrimethoxysilane, phenyltrimethoxysilane, methylphenyldimethoxysilane, and diphenyldimethoxysilane, siloxanes such as hexamethyldisiloxane, γ-chloropropyltrimethoxysilane, vinyltrimethyl. Chlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-ureido Examples thereof include propyltriethoxysilane. Examples of titanium coupling agents include TTS, 9S, 38S, 41B, 46B, 55, 138S, and 238S, which are commercially available under the trade name “Plenact” manufactured by Ajinomoto Co., Inc. -1, B-1, TOT, TST, TAA, TAT, TLA, TOG, TBSTA, A-10, TBT, B-2, B-4, B-7, B-10, TBSTA-400, TTS, TOA -30, TSDMA, TTAB, TTOP and the like. Examples of the aluminum coupling agent include “Plenact AL-M” manufactured by Ajinomoto Co., Inc.
[0262]
The addition amount of these surface modifiers is preferably 0.01 to 20% by mass, more preferably 0.1 to 5% by mass with respect to the colorant. Examples of the surface modification method for the colorant particles include a method in which a surface modifier is added to the dispersion of the colorant particles and this system is heated and reacted. The colorant particles whose surface has been modified in this manner are obtained by filtration, and after drying and filtering with the same solvent are repeated, drying is performed.
[0263]
The image forming method of the present invention will be described.
In the image forming method of the present invention, a latent image forming step for forming a latent image on the latent image carrier, a developing step for developing the latent image with toner, and a latent image carrier formed on the latent image carrier. An image forming method comprising: a transfer step of transferring a toner image onto a transfer member; and a fixing step of heating and fixing the toner image on the transfer member using a heating member, wherein the toner is the toner of the present invention. The heating member has an elastic layer. According to the image forming method of the present invention, since the toner of the present invention is used, it is possible to obtain a high image quality that is excellent in offset resistance and OHP transparency and is free from unpleasant glare.
[0264]
The elastic layer in the heating member has a role of improving the image quality, and is made of silicone rubber, fluorine-based rubber material, or the like. The thickness of the elastic layer can be appropriately selected according to the purpose, but is preferably 0.5 to 5.0 mm.
[0265]
The heating member preferably has a release layer. The release layer is preferably formed of a material excellent in releasability with respect to the toner, for example, a fluorine resin, for the purpose of preventing the toner from adhering. Specific examples of the fluororesin include, for example, a copolymer of tetrafluoroethylene and perfluoroalkyl vinyl ether, a copolymer of tetrafluoroethylene and ethylene, and a copolymer of tetrafluoroethylene and hexafluoroethylene. Preferably mentioned. The thickness of the release layer can be appropriately selected according to the purpose, but is preferably 10 to 60 μm.
[0266]
At this time, it is preferable not to apply a releasable liquid such as silicone oil applied to the heating member. The releasable liquid is effective for fixing latitude, but is transferred to the transfer material to be fixed, so that there is stickiness, tape cannot be pasted, characters cannot be written by magic, etc. There's a problem. This is remarkable for OHP. In addition, since the releasable liquid cannot smooth the fixing surface, it also causes a decrease in OHP transparency. In the toner configuration of the present invention, a sufficient amount of releasing liquid such as silicone oil applied to the fixing roll is sufficient in order to exhibit a sufficient fixing latitude. For example, it may be 1 μl or less per A4 sheet. If it is in this range, the above-mentioned problems can be substantially avoided. In the toner configuration of the present invention, a sufficient fixing latitude is exhibited even without applying a releasable liquid, and therefore the releasable liquid application mechanism can be removed in order to save space.
[0267]
When the heating member is composed of two rolls, the surface of the roll that comes into contact with the toner image on the transfer object is more greatly recessed than the other roll surface to form a nip. It is preferable that winding of the transfer body around the roll hardly occurs. For example, the thickness of the elastic layer in the roll in contact with the toner image on the transfer medium is 2 mm, the thickness of the elastic layer in the other roll is 1 mm, or the hardness of the elastic layer is the same thickness. This can be achieved by setting the roll in contact with the toner image on the transfer body low and applying a load. With this configuration, the discharge direction of the transfer medium immediately after passing through the fixing roll becomes a direction away from the roll in contact with the toner image on the transfer medium, so that winding does not easily occur.
[0268]
It is preferable from the viewpoint of power consumption that the heating member is composed of a single roll and a belt, and that the roll is in contact with the toner image on the transfer medium, since the heat capacity of the belt is small. The belt material is preferably a heat-resistant material such as tetrafluoroethylene or polyimide, and the belt layer thickness is preferably 2 mm or less, and the surface is preferably coated with a fluorine resin equivalent to the heating member. Further, by applying pressure from the inside of the belt to the roll in contact with the toner image on the transfer medium via the belt to form a dent, the discharge direction of the transfer medium immediately after passing through the fixing roll is adjusted. The direction is away from the roll in contact with the toner image on the transfer body, and winding is less likely to occur.
[0269]
The surface temperature of the heating member is preferably 30 ° C. or more higher than the temperature at the DSC endothermic peak of the wax contained in the toner of the present invention, and more preferably 50 ° C. or more. If the surface temperature is not higher by 30 ° C. or more than the DSC endothermic peak temperature of the wax, the wax release effect may not be fully exhibited.
[0270]
When using a contact type, such as a thermocouple, as the temperature control sensor of the heating member, the surface of the heating member is easily worn in the configuration of the present invention, unlike the conventional type in which a large amount of releasable liquid is applied. If the position of the temperature control sensor is present in the image area, image quality defects occur, so it is preferable to set the temperature control sensor in the non-image area. The non-image portion includes a portion where the paper does not pass and an end portion where the toner is not transferred onto the paper.
[0271]
Hereinafter, an image forming apparatus used in the image forming method of the present invention will be described with reference to FIG. The image forming apparatus used in the image forming method of the present invention is not limited to the one shown in FIG.
[0272]
FIG. 4A is a schematic cross-sectional view showing the configuration in the vicinity of the developing device of the embodiment, and FIG. As shown in the figure, the developing device 3 (also referred to as the developing device 3) is configured such that the developing sleeve (developer carrier) 140 faces the photosensitive drum (electrostatic latent image carrier) 1 so as to face the photosensitive drum 1. It is provided in the position close | similar to the surrounding surface. Further, a positioning member (0.1 mm thick polyester film) 160 is interposed between the developing sleeve 140 and the photosensitive drum 1, and thereby, a gap (gap) between the developing sleeve 140 and the photosensitive drum 1. ) The distance Ds is set to a predetermined value.
[0273]
In the hopper 120 of the developing device 3, the non-magnetic one-component toner used in the present invention is stored, and is conveyed through the developing device 3 by a screw, a stirring blade or the like, and reaches the developing sleeve 140. The toner reaching the developing sleeve 140 is charged to a predetermined polarity by friction with a regulating member (eg, 0.1 mm thick SUS (stainless steel) plate) 150 and is carried in a thin layer on the peripheral surface of the developing sleeve 140. The The thickness of the thin layer is determined by the material and pressing force of the regulating member 150. In this example, the circumferential speed of the photosensitive drum 1 is 100 mm / sec, the circumferential speed of the developing sleeve 140 is 200 mm / sec, and the regulating member 150 is By setting the pressing force for pressing the developing sleeve 140 to 10 to 100 N / m, the thickness is about 1.5 layers (thickness about 1.5 toner particles). A process in which the toner is charged to a predetermined polarity by frictional charging with the regulating member 150 and is carried on the peripheral surface of the developing sleeve 140 in a thin layer is described in, for example, Japanese Patent Publication No. 63-15580. Since it is publicly known, the description is omitted.
[0274]
The developing sleeve 140 is formed into a cylindrical shape (for example, a diameter of 17 mm) using a flexible conductive material (for example, a polyamide resin having a thickness of 1 mm). Inside the developing sleeve 140 is housed a driving roller 130 whose diameter is slightly smaller than the developing sleeve 140 (for example, 16 mm in diameter), and when the driving roller 130 rotates in the direction of the arrow, the outer peripheral surface of the driving roller 130 The developing sleeve 140 is driven by the frictional force between the developing sleeve 140 and the inner peripheral surface of the developing sleeve 140 and rotates in the same direction. Further, as described above, since the developing sleeve 140 is flexible and slightly larger in diameter than the driving roller 130, there is a slight slack. This slack is regulated by the regulating member 150 and a guide belt (not shown) so as to occur on the side facing the photosensitive drum 1. Therefore, a part of the pressing force from the developing sleeve 140 is absorbed by the slack, and as a result, from the developing sleeve 140 to the positioning member 160 inserted between the developing sleeve 140 and the photosensitive drum 1. The applied pressing force is relatively low.
[0275]
The toner carried in a thin layer on the peripheral surface of the developing sleeve 140 is conveyed along with the rotation of the developing sleeve 140 and reaches the developing area Da. The developing area Da is a toner on the peripheral surface of the developing sleeve 140 that flies from the peripheral surface of the developing sleeve 140 by the action of an electric field formed by the developing bias voltage Vb and the alternating voltage applied from the developing bias power supply device. This is an area where the powder cloud is formed and the electrostatic latent image on the peripheral surface of the photosensitive drum 1 is developed. This region is also a region within the nip width Da between the developing sleeve 140 and the photosensitive drum 1. The development bias power supply device includes a DC voltage power supply that outputs a set value (eg, about −500 V) of the development bias voltage Vb, and an AC power supply device that forms an alternating electric field (eg, Vpp 2.0 kV, frequency 2 kHz). It is configured.
[0276]
Regarding the process of developing the electrostatic latent image on the photosensitive member by converting the toner flying from the developing sleeve by the alternating electric field into a powder cloud, see, for example, the basics and applications of electrophotographic technology (Electrophotographic Society, Corona). Since it is publicly known as described on pages 158 to 170, description thereof is omitted. Vpp means a peak-to-peak voltage that is the difference between the peak and valley of the amplitude of the alternating voltage waveform.
[0277]
In this example, the photoconductor drum 1 is a photoconductive drum having a surface composed of a negatively chargeable organic photoconductor and rotating at a constant speed in the direction of the arrow in the figure. The photosensitive drum 1 is charged to a uniform potential (eg, about −800 V) by a charging device (not shown), and then exposed to an optical head such as a laser to attenuate the potential (eg, about −100 V). ). That is, an electrostatic latent image is formed. When the electrostatic latent image reaches the development area Da, the toner that has been turned into a powder cloud as described above adheres to the potential decay portion and development is performed.
[0278]
The positioning member 160 includes a developing sleeve 140 and the photosensitive drum 1 such that a front end edge portion (lower end portion in the drawing) 16a is positioned in the developing area Da and parallel to the longitudinal direction of the developing area Da. Is interposed between the developing sleeve 140 and the photosensitive drum 1 at a position on the upstream side in the rotation direction (a position on the upper half side in the figure). As a result, the gap distance Ds between the developing sleeve 14 and the photosensitive drum 1 is set to a predetermined value, and since the leading edge 16a is provided along the longitudinal direction, the gap distance Ds over the entire image width. It is set to an appropriate value. In this example, the positioning member 160 is a 0.1 mm thick polyester film as described above, but is not limited to a polyester film. The material may be selected in consideration of the balance with the frictional charging of the toner. For example, by using a charging series material having a polarity opposite to the charging polarity of the toner, the frictional charging by the regulating member 150 is supplemented or promoted. It may be configured. In addition, the surface contacting the developing sleeve 140 is made of a conductive material and a voltage having the same polarity as the toner charging polarity is applied to prevent toner adhesion and assist toner charging. You may make it do.
[0279]
Further, in this example, the positioning member 160 is provided on the upstream side of the rotation of the developing sleeve 140 and the photosensitive drum 1 as shown in the figure, and shields the upstream side portion in the developing area Da, but it is downstream. It may be provided on the side to shield the downstream portion in the development area Da. When provided on the upstream side as in this example, the positioning member 160 is provided along the rotation direction, so that the resistance received from the developing sleeve 140 and the photosensitive drum 1 is reduced, causing a problem in toner flying. The effect is difficult. Further, even when at least one of the developing sleeve 140 and the photosensitive drum 1 is flexible or elastic, there is an effect that the gap distance Ds can be set to an appropriate value.
[0280]
Next, the relationship between the position of the leading edge 16a of the positioning member 160, the gap distance Ds between the developing sleeve 140 and the photosensitive drum 1, and the toner adhesion amount will be described. The flying of toner from the surface of the developing sleeve 140 and the formation of a powder cloud are mainly determined by the gap distance Ds, the width Da of the developing region in the rotation direction, and the developing bias voltage Vb. In the case of forming an alternating electric field, the amplitude difference voltage Vp-p of the applied voltage waveform also contributes. In the case of configuring a flying type developing device, it is relatively easy to improve the accuracy on the power source side, but it is difficult to stably secure the gap distance Ds. For this reason, in this example, the positioning member 160 is used.
[0281]
Although the gap distance Ds can be easily set to an appropriate value by the positioning member 160 as described above, a part of the developing region (upper portion in the illustrated example) is shielded by the presence of the positioning member 160. For this reason, the amount of toner adhesion on the photosensitive drum 1 is reduced, resulting in a problem that the development density is lowered. 0.7 mg / cm to obtain sufficient print image density²It is sufficient if the toner adhesion amount is as described above, and a sufficient toner adhesion amount can be obtained by securing the development nip width Da of 1.5 mm or more.
[0282]
For this reason, it is necessary to set the position of the leading edge 16a of the positioning member 160 within a range where the development nip width Da is 1.5 mm or more.
[0283]
Various modifications of the above example are possible. For example, the amplitude voltage difference Vpp for forming the alternating electric field may be about 100 to 3000 V, the frequency may be about 100 to 10 kHz, and the waveform may be a triangular wave or a rectangular wave. Moreover, about 0.01-0.5 mm can be used as the thickness of the positioning member 160, and it can also be used in combination with the above-mentioned alternating electric field. A magnetic toner can be used in place of the non-magnetic toner. Further, a developing roller can be used in place of the flexible developing sleeve, and the photoconductor can be configured to have elasticity. Further, the positioning member 160 can be detached from the non-image printing area to be used as a simultaneous development cleaning device.
[0284]
FIG. 5 is a schematic configuration diagram illustrating an example of a color electrophotographic image forming apparatus.
In the main body of the color electrophotographic image forming apparatus, first, second, third and fourth image forming portions Pa, Pb, Pc and Pd are installed in parallel. Each image forming unit has the same configuration, and forms visible images (toner images) of different colors.
[0285]
The image forming portions Pa, Pb, Pc, and Pd include dedicated electrostatic latent image carriers (electrophotographic photosensitive drums) 1a, 1b, 1c, and 1d, respectively. The images on the electrophotographic photosensitive drums 1a, 1b, 1c, and 1d formed by the image forming units Pa, Pb, Pc, and Pd are adjacent to the image forming units. Then, the image is transferred onto a recording material (transfer material, image support) carried and conveyed on the recording material carrier 18 that moves. Further, the image on the recording material is fixed by heating and pressurizing by the fixing unit (fixing device) 10, and the recording material is discharged to the tray 61.
[0286]
Next, the latent image forming unit in each image forming unit will be described. Disposed on the outer periphery of each of the photosensitive drums 1a, 1b, 1c, and 1d are static elimination exposure lamps 21a, 21b, 21c, and 21d, drum chargers 2a, 2b, 2c, and 2d, a laser beam exposure device 17 as an image exposure unit, and an electric potential. Sensors 22a, 22b, 22c, and 22d are provided. The photosensitive drums 1a, 1b, 1c, and 1d that have been neutralized by the neutralizing exposure lamps 21a, 21b, 21c, and 21d are uniformly charged by the drum chargers 2a, 2b, 2c, and 2d, and then the laser beam exposure device 17 As a result of the exposure, a color-separated electrostatic latent image corresponding to the image signal is formed on the photosensitive drums 1a, 1b, 1c, and 1d. In the image forming apparatus of the present invention, as the image exposure means, in addition to the laser beam exposure apparatus 17 described above, a light quantity level other than OFF in a basic image unit (pixel) such as an LED array exposure apparatus is used. Well-known multi-value exposure means that can irradiate can be suitably employed.
[0287]
The electrostatic latent image on the photosensitive drum is developed by a developing unit to become a visible image. That is, the developing means includes developing devices 3a, 3b, 3c, and 3d filled with a predetermined amount of cyan, magenta, yellow, and black developers, respectively, and the photosensitive drums 1a, 1b, and 1c. The electrostatic latent image formed on 1d is developed into a visible image (toner image).
[0288]
Next, the transfer part will be described. The recording material held in the recording material cassette 60 is fed to the recording material carrier 18 through a registration roller.
[0289]
When the recording material carrier 18 starts to rotate, the recording material is conveyed from the registration roller onto the recording material carrier 18. At this time, the image writing signal is turned ON, and an image is formed on the first electrophotographic photosensitive drum 1a at an appropriate timing.
[0290]
A transfer charger 4a and a transfer pressing member 41a are provided below the first electrophotographic photosensitive drum 1a, and the transfer pressing member 41a applies a uniform pressing force toward the photosensitive drum. Then, the transfer charger 4a applies an electric field to transfer the toner image on the photosensitive drum 1a onto the recording material. At this time, the recording material is held on the recording material carrier 18 by an electrostatic attraction force, and the recording material is conveyed to the second image forming portion Pb, and the next transfer is performed. Thereafter, the recording material on which the toner images formed by the third and fourth image forming portions Pc and Pd are transferred by the same method as described above is neutralized by a separation charger (separation electrode) 9 and is subjected to electrostatic attraction force. As a result of this attenuation, the recording material carrier 18 is separated from the recording material carrier 18 and conveyed to a fixing unit (fixing device) 10.
[0291]
The fixing unit 10 includes a fixing roller 71, a pressure roller 72, heat resistant cleaning members 73 and 74 for cleaning the rollers 71 and 72, heaters 75 and 76 for heating the rollers 71 and 72, and a release agent such as dimethyl silicone. An oil application roller 77 for applying oil to the fixing roller 71, an oil reservoir 78 for supplying the oil, and a thermistor 79 for fixing temperature control are included.
[0292]
After the transfer, the toner remaining on the photosensitive drums la, lb, lc, and ld is removed by the photosensitive member cleaning units 5a, 5b, 5c, and 5d, and is prepared for the subsequent latent image formation. Further, the toner and the like remaining on the image support 8 are removed by the belt static eliminator 12 and the electrostatic adsorption force is removed, and then removed by the cleaning device 62 having a nonwoven fabric in this example. As the cleaning device 62, a rotating fur brush, a blade, or a device using these in combination is also used.
[0293]
As a suitable fixing method used in the present invention, a so-called contact heating method will be described with reference to FIGS.
[0294]
7 and 8 are schematic cross-sectional views each showing one embodiment of the fixing device used in the present invention.
[0295]
In the present invention, in particular, as a contact heating method, a heat pressure fixing method, a heat roll fixing method, and a pressure heating fixing method in which fixing is performed by a rotating pressure member including a fixedly arranged heating body can be given. it can.
[0296]
7 and 8, in many cases, a metal cylinder composed of iron, aluminum, or the like whose surface is coated with tetrafluoroethylene or polytetrafluoroethylene-perfluoroalkoxy vinyl ether copolymers or the like. It is formed of an upper roller having a heat source therein and a lower roller formed of silicone rubber or the like. A typical example of the heat source is one that has a linear heater and heats the surface temperature of the upper roller to about 120 to 200 ° C. In the fixing unit, pressure is applied between the upper roller and the lower roller, and the lower roller is deformed to form a so-called nip. The nip width is 1 to 10 mm, preferably 1.5 to 7 mm. The fixing linear velocity is preferably 40 mm / sec to 600 mm / sec.
[0297]
A fixing cleaning mechanism may be provided for use. As this method, a method of supplying silicone oil to the upper roller or film for fixing, or a method of cleaning with a pad, roller, web or the like impregnated with silicone oil can be used.
[0298]
Next, a method for fixing by a rotating pressure member including a fixedly arranged heating body used in the present invention will be described.
[0299]
This fixing method is a method in which pressure fixing is carried out by a fixedly arranged heating body and a pressure member that is opposed to the heating body and presses the transfer material in close contact with the heating body through a film.
[0300]
In this press-contact fixing device, the heating body has a smaller heat capacity than a conventional heating roller, and has a line-shaped heating portion in a direction perpendicular to the passing direction of the transfer material. 300 ° C.
[0301]
The pressure contact fixing is a method of fixing an unfixed toner image against a heating source, such as a method in which a transfer material with unfixed toner is passed between a heating member and a pressure member as is usually used. is there. In this way, since the heating is performed quickly, the fixing speed can be increased. However, the temperature control is difficult, and the toner remains attached to the portion where the unfixed toner is directly pressed against the surface of the heating source or the like. There are also problems that toner offset is likely to occur, and that the transfer material is likely to fail such as winding around the fixing device.
[0302]
In this fixing method, the low-heat capacity line-shaped heating element fixedly supported by the apparatus has a thickness of 0.2 to 5.0 mm, more preferably 0.5 to 3.5 mm, a width of 10 to 15 mm, and a longitudinal length. A 240-400 mm alumina substrate is coated with a resistance material at 1.0-2.5 mm and is energized from both ends.
[0303]
The energization is performed by changing the pulse width according to the temperature / energy release amount controlled by the temperature sensor in a pulse waveform with a cycle of 15 to 25 msec of DC 100V. In the low heat capacity line-shaped heating element, in the case of the temperature T1 detected by the temperature sensor, the surface temperature T2 of the film facing the resistance material is lower than T1. Here, T1 is preferably 120 to 220 ° C, and the temperature of T2 is preferably 0.5 to 10 ° C lower than the temperature of T1. Further, the film material surface temperature T3 at the portion where the film peels from the toner surface is substantially equal to T2. The film moves in the direction of the center arrow in FIG. 9A while coming into contact with the heating body whose energy and temperature are controlled in this way. What is used as these fixing films is a heat-resistant film having a thickness of 10 to 35 μm, such as polyester, polyperfluoroalkoxy vinyl ether, polyimide, polyetherimide, and in many cases a conductive material such as Teflon (R) or other fluorine resin. Is an endless film coated with 5 to 15 μm of the release agent layer.
[0304]
For driving the film, a driving force and tension are applied by a driving roller and a driven roller, and the film is transported in the direction of the arrow without wrinkles or twists. The linear velocity as the fixing device is preferably 40 to 600 mm / sec.
[0305]
The pressure roller has a rubber elastic layer having high releasability, such as silicone rubber, and is pressure-bonded to a heating body via a film material, and is pressed and rotated.
[0306]
Moreover, although the example using an endless film was demonstrated above, as shown in FIG.9 (b), you may use the film material of a end using the sending-out axis | shaft and winding axis | shaft of a film sheet. Furthermore, it may be a simple cylinder having no driving roller or the like inside.
[0307]
The fixing device may be used with a cleaning mechanism. As a cleaning method, a method of supplying various silicone oils to the fixing film, or a method of cleaning with a pad, roller, web or the like impregnated with various silicone oils is used.
[0308]
As the silicone oil, polydimethylsiloxane, polymethylphenylsiloxane, polydiphenylsiloxane, or the like can be used. Furthermore, siloxane containing fluorine can also be suitably used.
[0309]
Next, FIG. 9 shows an example of a sectional view of the fixing device.
In FIG. 9A, reference numeral 84 denotes a low heat capacity line-shaped heating element fixedly supported by the apparatus. As an example, a resistance material 86 is applied to an alumina substrate 85 having a height of 1.0 mm, a width of 10 mm, and a longitudinal length of 240 mm. Is applied to a width of 1.0 mm and is energized from both ends in the longitudinal direction.
[0310]
The energization is, for example, DC100V and is usually a pulse waveform with a cycle of 20 msec, and is controlled by a signal from the temperature measuring element 87 and kept at a predetermined temperature. For this reason, the pulse width is changed according to the amount of energy released, and the range is, for example, 0.5 to 5 msec.
[0311]
The transfer material 94 carrying the unfixed toner image 93 is brought into contact via the film 88 moving to the heating body 84 controlled in this way, and the toner is thermally fixed.
[0312]
The film 88 used here moves without wrinkles while being tensioned by the driving roller 89 and the driven roller 90. Reference numeral 95 denotes a pressure roller having a rubber elastic layer formed of silicone rubber or the like, and pressurizes the heating body through a film with a total pressure of 0.4 to 2.0 N. The unfixed toner image 93 on the transfer material 94 is guided to the fixing unit by the entrance guide 96, and a fixed image is obtained by heating.
[0313]
The endless belt has been described above. However, as shown in FIG. 9B, a film sheet feeding shaft 91 and a take-up shaft 92 may be used, and the fixing film may be a terminal film.
[0314]
【Example】
EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated in detail, the aspect of this invention is not limited to this. In the text, “part” means “part by mass”.
[0315]
Example 1
<Production example of resin particles>
(Manufacture of resin particle S1)
430 parts of deionized water was placed in a separable flask equipped with a thermometer, reflux condenser, stirrer, and monomer charger, and after replacing oxygen with nitrogen gas, the temperature was raised to 70 ° C. and potassium persulfate (KPS ) 5 parts were added and stirred.
[0316]
A separable flask equipped with the same apparatus as described above was prepared. As the vinyl polymerizable monomer, 44 parts of methyl methacrylate (MMA), 44 parts of n-butyl acrylate, and as the polymerizable monomer A, compound (1- 1) 100 parts of (2,2,2-trifluoroethyl methacrylate), polymerizable monomer B having an acidic polar group, 12 parts of methacrylic acid, a chain transfer agent, and n-octyl-3-mercapto Emulsified with 1 part of propionate with 480 parts of deionized water and 9 parts of anionic surfactant (sodium dodecylbenzenesulfonate: SDS) as a seed, added to a separable flask containing potassium persulfate as a seed 20% Polymerized for minutes.
[0317]
Furthermore, the remaining emulsion was dripped continuously in the flask over 5 hours. After further reacting at 75 ° C. for 3 hours, the mixture was cooled to 50 ° C., diluted 5 times with ion-exchanged water, adjusted to pH 8 with aqueous ammonia, and resin particles S1 were obtained.
[0318]
(Production of resin particles S2 to S5 and S8)
In the production of the resin particles S1, except that the polymerizable monomer A, the polymerizable monomer B, and the vinyl polymerizable monomer are changed as shown in Table 1, resin particles S2 to S5, and Each S8 was manufactured.
[0319]
(Manufacture of resin particle S6)
Place 998 parts of deionized water in a separable flask equipped with a thermometer, reflux condenser, stirrer and monomer charger, replace oxygen with nitrogen gas, raise the temperature to 72 ° C., and add 5 parts of potassium persulfate. Stirring was performed.
[0320]
A separable flask equipped with the same apparatus as described above was prepared. As the vinyl polymerizable monomer, 44 parts of methyl methacrylate (MMA), 44 parts of n-butyl acrylate, and as the polymerizable monomer A, compound (1- 1) 100 parts of 2,2,2-trifluoroethyl methacrylate, 12 parts of methacrylic acid as polymerizable monomer B, and 1 part of n-octyl-3-mercaptopropionic acid ester as chain transfer agent 191 5% of the emulsion emulsified with 2 parts of SDS was added to a separable flask containing potassium persulfate as a seed and polymerized for 20 minutes. Furthermore, the remaining emulsion was dripped continuously in the flask over 1.5 to 2 hours to form a core part.
[0321]
Then, the reaction was allowed to proceed for 1 hour. Similarly to the core part, 44 parts of methyl methacrylate (MMA), 44 parts of n-butyl acrylate as the vinyl polymerizable monomer, 12 parts of methacrylic acid as the polymerizable monomer B, chain transfer What was emulsified and emulsified with 1 part of n-octyl-3-mercaptopropionic acid ester was dropped continuously into the 3 liter separable flask over 1 to 2 hours to form a shell part.
[0322]
Then, the mixture was further reacted at 75 ° C. for 2 hours, then cooled to 50 ° C. and adjusted to pH 8 with aqueous ammonia to obtain resin particles S6 having a core-shell structure.
[0323]
(Manufacture of resin particle S7)
Place 998 parts of deionized water in a separable flask equipped with a thermometer, reflux condenser, stirrer and monomer charger, replace oxygen with nitrogen gas, raise the temperature to 72 ° C., and add 5 parts of potassium persulfate. Stirring was performed.
[0324]
A separable flask equipped with the same apparatus as described above was prepared, and 44 parts of methyl methacrylate (MMA), 44 parts of n-butyl acrylate as a vinyl polymerizable monomer, 12 parts of methacrylic acid as a polymerizable monomer B As a chain transfer agent, 1 part of n-octyl-3-mercaptopropionate was emulsified with 191 parts of deionized water and 2.2 parts of SDS, and 5% of the seed was used as a seed in a separable flask containing potassium persulfate. Polymerized for 20 minutes. Furthermore, the remaining emulsion was dripped continuously in the flask over 1.5 to 2 hours to form a core part.
[0325]
Thereafter, the mixture was reacted for 1 hour, and similarly to the core part, as the vinyl polymerizable monomer, 44 parts of methyl methacrylate (MMA), 44 parts of n-butyl acrylate, and as the polymerizable monomer A, compound (1-1) ( 2,2,2-trifluoroethyl methacrylate) 100 parts, as polymerizable monomer B, 1 part emulsified with 12 parts methacrylic acid and 1 part n-octyl-3-mercaptopropionic acid ester as chain transfer agent It dripped continuously in the flask containing the said potassium persulfate over -2 hours, and was set as the shell part.
[0326]
Then, the mixture was further reacted at 75 ° C. for 2 hours, then cooled to 50 ° C. and adjusted to pH 8 with aqueous ammonia to obtain resin particles S7 having a core-shell structure.
[0327]
Table 1 shows a list of the structures, physical properties, and the like of the obtained resin particles S1 to S8.
[0328]
[Table 1]

[0329]
<Preparation of latex>
(Preparation of latex 1HML)
(1) Preparation of core particles (first stage polymerization):
A surfactant solution (aqueous medium) in which 7.08 g of the anionic surfactant shown below was dissolved in 3010 g of ion-exchanged water in a 5000 ml separable flask equipped with a stirrer, a temperature sensor, a condenser, and a nitrogen introducing device. The temperature in the flask was raised to 80 ° C. while charging and stirring at a stirring speed of 230 rpm under a nitrogen stream.
[0330]
(101) C_TenH_{twenty one}(OCH₂CH₂)₂OSO_ThreeNa
To this surfactant solution, an initiator solution in which 9.2 g of a polymerization initiator (potassium persulfate) was dissolved in 200 g of ion-exchanged water was added, the temperature was adjusted to 75 ° C., and then 70.1 g of styrene and n-butyl. A monomer mixture consisting of 19.9 g of acrylate and 10.9 g of methacrylic acid was added dropwise over 1 hour, and this system was polymerized by heating and stirring at 75 ° C. for 2 hours (first stage polymerization). A latex (a dispersion of resin particles made of a high molecular weight resin) was prepared. This is referred to as “latex (1H)”.
[0331]
(2) Formation of intermediate layer (second stage polymerization);
In a flask equipped with a stirrer, 105.6 g of styrene, 30.0 g of n-butyl acrylate, 6.2 g of methacrylic acid, 5.6 g of n-octyl-3-mercaptopropionic acid ester, As a crystalline substance, 98.0 g of the compound represented by the above 19) (hereinafter referred to as “Exemplary Compound 19”) was added, heated to 90 ° C. and dissolved to prepare a monomer solution.
[0332]
On the other hand, a surfactant solution obtained by dissolving 1.6 g of an anionic surfactant (the above formula (101)) in 2700 ml of ion-exchanged water is heated to 98 ° C., and a dispersion of core particles is added to the surfactant solution. After adding 28 g of the latex (1H) in terms of solid content, a single amount of the exemplified compound 19) is obtained by a mechanical disperser “CLEARMIX” (manufactured by M Technique Co., Ltd.) having a circulation path. The body solution was mixed and dispersed for 8 hours to prepare a dispersion (emulsion) containing emulsified particles (oil droplets).
[0333]
Next, an initiator solution prepared by dissolving 5.1 g of a polymerization initiator (KPS) in 240 ml of ion exchange water and 750 ml of ion exchange water are added to this dispersion (emulsion). Polymerization (second-stage polymerization) was performed by heating and stirring for 12 hours to obtain latex (a dispersion of composite resin particles having a structure in which the surface of resin particles made of a high molecular weight resin was covered with an intermediate molecular weight resin). This is referred to as “latex (1HM)”.
[0334]
When the latex (1HM) was dried and observed with a scanning electron microscope, particles (400 nm to 1000 nm) containing, as a main component, exemplary compound 19) not surrounded by latex were observed.
[0335]
(3) Formation of outer layer (third stage polymerization):
An initiator solution obtained by dissolving 7.4 g of a polymerization initiator (KPS) in 200 ml of ion-exchanged water is added to the latex (1HM) obtained as described above, and 300 g of styrene under a temperature condition of 80 ° C. A monomer mixture composed of 95 g of n-butyl acrylate, 15.3 g of methacrylic acid, and 10.4 g of n-octyl-3-mercaptopropionic acid ester was added dropwise over 1 hour. After completion of the dropwise addition, polymerization (third stage polymerization) was performed by heating and stirring for 2 hours, followed by cooling to 28 ° C. and latex (a central part made of a high molecular weight resin, an intermediate layer made of an intermediate molecular weight resin, A dispersion of composite resin particles having an outer layer made of a molecular weight resin and containing the exemplified compound 19) in the intermediate layer was obtained. This latex is referred to as “latex (1HML)”.
[0336]
<< Preparation of colored particles >>
(Preparation of colored particles 1-8)
The composite resin particles constituting the latex (1HML) had peak molecular weights of 138,000, 80,000 and 13,000, and the weight average particle size of the composite resin particles was 122 nm.
[0337]
SDS 59.0 g was dissolved in 1600 ml of ion-exchanged water with stirring. I. Pigment red 122 420.0 g was gradually added, and then dispersion treatment was performed using “CLEARMIX” (manufactured by M Technique Co., Ltd.), whereby a dispersion of colorant particles (hereinafter “colorant dispersion 1”). Prepared). When the particle diameter of the colorant particles in this colorant dispersion was measured using an electrophoretic light scattering photometer “ELS-800” (manufactured by Otsuka Electronics Co., Ltd.), the weight average particle diameter was 89 nm.
[0338]
Latex 1 HML 420.7 g (converted to solid content), ion-exchanged water 900 g, and 166 g of the colorant dispersion 1 are a reaction vessel (four-necked flask) equipped with a temperature sensor, a condenser, a nitrogen introducing device, and a stirring device. And stirred. After adjusting the temperature in the container to 30 ° C., a 5 mol / liter sodium hydroxide aqueous solution was added to this solution to adjust the pH to 8 to 10.0.
[0339]
Next, an aqueous solution obtained by dissolving 12.1 g of magnesium chloride hexahydrate in 1000 ml of ion-exchanged water was added at 30 ° C. over 10 minutes with stirring. After standing for 3 minutes, the temperature was started to rise, and the system was heated to 90 ° C. over 6 to 60 minutes to produce associated particles. In this state, the particle size of the associated particles was measured with “Coulter Counter TA-II”. When the number average particle size reached 5 μm, an aqueous solution in which 40.2 g of sodium chloride was dissolved in 1000 ml of ion-exchanged water was added. Then, the particle growth was temporarily stopped, and colored particles 1 were obtained.
[0340]
In addition, by controlling the pH of the agglomeration step, the temperature of the aging treatment step, the aging time, and the stirring strength, the coefficient of variation of the crystalline substance, the colorant dispersion state, the shape and the shape factor is controlled. Thus, the toner particle size and the coefficient of variation of the particle size distribution were arbitrarily adjusted to obtain colored particles 2 to 8.
[0341]
<Example of toner production>
(Manufacture of toners 1-8)
In the colored particles 1 to 8 obtained above, the mass ratio ((s) / (s + Mp) × 100)% of the mass (s) of the resin particles and the mass (Mp) of the colored particles is a numerical value described in Table 4. Each of the dispersions of resin particles S1 to S8 was added while being adjusted so as to become, and further heated and stirred at a liquid temperature of 98 ° C. for 2 hours as an aging treatment, and 40.2 g of sodium chloride was added to 1000 ml of ion-exchanged water. The melted aqueous solution was added to stop the ripening of the particles, and the particles were continuously fused by heating and stirring at a liquid temperature of 98 ° C. for 1 to 4 hours (ripening step).
[0342]
Then, it cooled to 30 degreeC, hydrochloric acid was added, pH was adjusted to 2.0, and stirring was stopped. The produced association particles are filtered, washed repeatedly with ion exchange water at 45 ° C., and then dried with hot air at 40 ° C. to obtain 0.8 parts by mass of hydrophobic silica and 1.0 part by mass of hydrophobic titanium oxide. Then, the peripheral speed of the rotor blade of a 10 liter Henschel mixer was set to 30 m / s and mixed for 25 minutes to obtain toners 1 to 8.
[0343]
(Production of Comparative Toner 1)
Further, in the production of the toner 1, a comparative toner 1 was obtained in the same manner except that the dispersion liquid of the resin particles S1 was not added.
[0344]
During the production of the toner described above, the shape and particle size of the colored particles described above are not changed at all by the addition of an external additive.
[0345]
(Production of Comparative Toner 2)
The dispersion of resin particles S1 was dried by a spray drying method to obtain resin particle S1 powder.
[0346]
(Prescription 1)
100 parts of styrene acrylic resin
C. I. pigment. red 122 10 parts
Resin particle S1 powder 2 parts
Exemplified compound 19) 8 parts
The above composition 1 is premixed with a Henschel mixer, biaxially extruded and kneaded, pulverized with a jet pulverizer, classified with an airflow classifier, then 0.8 parts by weight of hydrophobic silica, and 1.0% of hydrophobic titanium oxide. A part by mass was added, the peripheral speed of the rotary blade of the Henschel mixer was set to 30 m / s, and the mixture was mixed for 25 minutes to obtain a comparative toner 2.
[0347]
(Production of Comparative Toner 3)
150 parts of toluene was placed in the reaction vessel and the temperature was raised to the reflux temperature. A solution mixture of 75 parts of styrene, 25 parts by mass of 1H, 1H-perfluoro-n-octyl acrylate, and 2 parts of tert-butyl peroxybenzoate was added dropwise thereto, and the solution polymerization was completed in 7 hours under toluene reflux. Toluene was distilled off under reduced pressure to obtain compound (A).
[0348]
In a 2 liter four-necked flask equipped with a high-speed stirring device TK type homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), 600 parts of ion-exchanged water and 0. lmol / liter-Na_ThreePO_Four500 parts of the aqueous solution was added, the rotation speed was adjusted to 12000 rpm, and the mixture was heated to 70 ° C. Here, 1.0 mol / liter-CaCl₂70 parts of an aqueous solution was added to prepare an aqueous dispersion medium containing a minute hardly water-soluble dispersion stabilizer (calcium phosphate salt).
[0349]
On the other hand, as dispersoid
82 parts of styrene
18 parts of 2-ethylhexyl acrylate
C. I. pigment. 10 parts of red122
Exemplified compound 19) 8 parts
Compound (A) 2 parts
The above mixture was dispersed for 3 hours using an attritor (manufactured by Mitsui Kinzoku Co., Ltd.), and then 3 parts of 2,2′-azobis (2,4-dimethylvaleronitrile) was added to prepare a polymerizable monomer composition. did.
[0350]
Next, the polymerizable monomer composition is charged into the aqueous dispersion medium, and stirred for 10 minutes while maintaining the rotation speed of a high-speed stirrer at 12000 rpm in a nitrogen atmosphere at an internal temperature of 70 ° C., The polymerizable monomer composition was granulated. Thereafter, the agitator was changed to a propeller stirring blade, and the polymerization was completed by maintaining at the same temperature for 10 hours while stirring at 50 rpm. After completion of the polymerization, the suspension was cooled, and then diluted hydrochloric acid was added to remove the dispersion stabilizer. The water washing was repeated several times and then dried, and then 0.8 parts by weight of hydrophobic silica and 1.0 parts by weight of hydrophobic titanium oxide were added, and the peripheral speed of the rotor blades of the Henschel mixer was set to 30 m / s. Then, the toner 3 for comparison was obtained by mixing for 25 minutes.
[0351]
(Production of Comparative Toner 4)
2 parts of resin particle S1 powder was added to 100 parts of comparative toner 1, and mixed for 10 minutes with a Henschel mixer to obtain comparative toner 4.
[0352]
Physical property data of the toners 1 to 8 and the comparative toners 1 to 4 manufactured above (number average particle diameter, shape factor, variation coefficient of shape factor, ratio of colored particles without corners, variation coefficient of number distribution, m1 And the sum of m2) is shown in Table 2.
[0353]
[Table 2]

[0354]
[Table 3]

[0355]
[Table 4]

[0356]
When the physical property data of the toners 1 to 8 and the colored particles 1 to 8 shown in Table 2 are compared, the physical property data is the same. The reason for this is that, in the production of colored particles according to the present invention, the resin particles and the colorant are monitored during the salting out / fusion step and the shape control step, and by reaction control such as the stirring rotation speed and heating time, The variation coefficient of the shape and the shape factor is controlled, and the variation coefficient of the particle size and the particle size distribution is adjusted.
[0357]
The toner particles are produced by adding external additives to the colored particles thus obtained, and the external additives are merely fixed on the surface of the toner particles and do not physically change the colored particles. The physical properties (shape, particle size, etc.) of the obtained toner particles are the same as those of the colored particles.
[0358]
<< Manufacture of photoconductor P1 >>
The following coating solution was applied onto a cylindrical conductive support having a length of 380 mm and a diameter of 60 mm to produce a photoreceptor P1.
[0359]
<Underlayer>
Titanium chelate compound (TC-750: Matsumoto Pharmaceutical Co., Ltd.) 30g
Silane coupling agent (KBM-503: manufactured by Shin-Etsu Chemical Co., Ltd.) 17g
150 ml of 2-propanol
It apply | coated so that it might become a film thickness of 0.5 micrometer on the cylindrical conductive support body using the said coating liquid.
[0360]

The above materials were mixed and dispersed for 10 hours using a sand mill to prepare a charge generation layer coating solution. This coating solution was applied onto the undercoat layer by a dip coating method to form a charge generation layer having a thickness of 0.2 μm.
[0361]

The above materials were mixed and dissolved to prepare a charge transport layer coating solution. This coating solution was applied onto the charge generation layer by a dip coating method to form a charge transport layer having a dry film thickness of 20 μm.
[0362]
<Protective layer>
150g of methyltrimethoxysilane
Dimethyldimethoxysilane 30g
Reactive charge transport compound (Exemplary Compound B-1) 15 g
Polyvinylidene fluoride particles (volume average particle size 0.2 μm) 10 g
Antioxidant (Exemplary Compound 2-1) 0.75 g
2-propanol 75g
3% acetic acid 5g
The above materials were mixed to prepare a coating solution for the resin layer. A 2 μm-thick resin layer is formed on the charge transport layer on the charge transport layer by using a circular amount-regulating coating apparatus, and heat-cured at 120 ° C. for 1 hour to form a siloxane resin layer. Produced.
[0363]
[Chemical formula 5]

[0364]
[Chemical 6]

[0365]
[Chemical 7]

[0366]
Next, the photoconductor P1 and the toner described above are developed as they are in a digital copying machine (corona charging, laser exposure, reverse development, electrostatic transfer, nail separation, and cleaning blade) having the image forming process shown in FIG. It was installed and evaluated as an agent. The digital copying machine was evaluated under the following conditions.
[0367]
(Charging conditions)
Charger: Scorotron charger, initial charging potential adjusted to -750V
(Exposure conditions)
Set the exposure amount so that the potential of the exposed area is -50V.
[0368]
(Development conditions)
DC bias; -550V
Transfer pole; corona charging method
As the fixing device, the device shown in FIG. 6 was used. The linear velocity is 120 mm / sec, and the fixing device cleaning mechanism and silicon oil supply mechanism are not attached. The fixing temperature was controlled by the surface temperature of the heating roller, and was set to 165 ° C.
[0369]
As copying conditions, 500,000 copies were made continuously in a high-temperature and high-humidity environment (30 ° C., 80% RH), and the following evaluation items were evaluated.
[0370]
The evaluation was performed by copying an original image in which a character image having a pixel rate of 7%, a human face photo image, a solid white image, and a solid black image each into a quarter of A4, using A4 neutral paper. Went.
[0371]
"Evaluation item"
(Uniformity of halftone)
The uniformity (non-uniformity) of the halftone image due to the change in toner transportability after the above continuous 500,000 copies was evaluated. Visual evaluation was performed in four stages as follows.
[0372]
A: Uniform image without unevenness
B: Extremely thin stripes are present
C: There are several streaky thin irregularities but there is no practical problem
D: Several or more streaky irregularities exist
In the evaluation rank, A to C were accepted and D was rejected.
[0373]
(Fog)
Using solid white images, the occurrence of fogging at the initial stage and after 50,000 sheets was visually evaluated. Evaluation was performed by 3 ranks.
[0374]
A: No fog occurs
○: Occasional fogging (practical)
×: Continuous fogging
(Offset resistance)
After 1000 continuous prints on A4 size transfer paper, white paper was printed, and the occurrence of smudges on the white paper due to offset and the toner smears on the surface of the heat roller were visually evaluated. In addition, as a transfer paper used for evaluation, high-quality paper 200 g / m²A line image having a width of 0.3 mm and a length of 150 mm was formed parallel to the paper traveling direction (heat roller circumferential direction).
[0375]
A: Image offset and toner contamination on the heat roller are not seen at all
○: Image offset does not occur, but toner stains on the heat roller
X: Image offset is confirmed.
[0376]
The evaluation ranks are 、, ○ is acceptable, and × is unacceptable.
(Photoconductor filming)
The presence or absence of filming was determined by visually observing the surface of the photoreceptor after the above-mentioned continuous 500,000 copies.
[0377]
The obtained evaluation results are shown in Table 5.
[0378]
[Table 5]

[0379]
From Table 5, compared to the comparative sample, the sample of the present invention has excellent halftone uniformity, low fog, good offset resistance, and extremely good toner filming property of the photoreceptor. It is clear that
[0380]
【The invention's effect】
According to the present invention, the toner for developing an electrostatic charge image having excellent halftone uniformity, low fog, good offset resistance and no filming of the photoreceptor, the method for producing the toner, An image forming method using toner can be provided.
[Brief description of the drawings]
FIG. 1 is a schematic diagram illustrating a toner with or without corners.
FIG. 2 is a schematic diagram illustrating an example of toner particles having a sea-island structure according to the present invention.
FIG. 3 is a schematic diagram in which toner particles having a sea-island structure according to the present invention are divided by Voronoi polygons.
FIG. 4 is a cross-sectional view illustrating an example of an image forming apparatus applied to the present invention.
FIG. 5 is a schematic cross-sectional view showing an example of a color electrophotographic image forming apparatus.
FIG. 6 is a schematic cross-sectional view showing an embodiment of a fixing device used in the present invention.
FIG. 7 is a schematic cross-sectional view showing another embodiment of the fixing device used in the present invention.
FIG. 8 is a schematic cross-sectional view showing another embodiment of the fixing device used in the present invention.
FIG. 9 is a schematic cross-sectional view showing another embodiment of the fixing device used in the present invention.
[Explanation of symbols]
1, 1a, 1b, 1c, 1d Electrostatic latent image carrier (electrophotographic photosensitive drum, photosensitive drum)
2a, 2b, 2c, 2d drum charger
3, 3a, 3b, 3c, 3d Developer
4a, 4b, 4c, 4d Transfer charger
41a, 41b, 41c, 41d Transfer pressing member
5a, 5b, 5c, 5d Photoconductor cleaning unit
10 Fixing part (fixing device)
16a Tip edge
17 Laser beam exposure equipment
21a, 21b, 21c, 21d Static elimination exposure lamp
22a, 22b, 22c, 22d Potential sensor
160 Positioning member
Da Development nip width
Pa, Pb, Pc, Pd Image forming unit
8 Image carrier
11 Core of heating roll
12, 20 Heating roll
12a Heating roll coating layer
13 Heating member
21 Core of pressure roll
22 Covering layer of pressure roll
37 Heating member
38 Release protection layer
T Toner image
40 Heating member
41, 211, 221 Core
42, 212 Elastic layer (silicone resin layer)
43, 213, 222 Release layer (fluorine resin layer)
44, 214, 223 Heater
45 Temperature sensor
50 Endless belt
51-53 indicating roller
54 Base plate
55 Pressing auxiliary pad
56 Press pad
71, 72 Heating roller
73, 74 Heat-resistant cleaning member
75, 76 heater
77 Oil application roller
78 Oil sump
79 Thermistor
210 Heating roller
220 Pressure roller

Claims (14)

Resin particles having a polymer formed by polymerization of a polymerizable monomer A having a silicon atom or a fluorine atom and a polymerizable monomer B having an acidic polar group, and a colored particle containing a binder resin and a colorant Toner particles are prepared through a step of adding metal oxide particles hydrophobized after being fused to the surface of the resin particles by a salting-out / fusing method , and the polymerizable monomer A of the resin particles A toner for developing an electrostatic charge image , wherein the polymer concentration is uniform or continuously or discontinuously changes from the resin particle surface to the inside . 2. The electrostatic image developing toner according to claim 1, wherein the polymerizable monomer A is represented by the following general formula (1).

[Wherein, R ¹ represents a hydrogen atom or a methyl group, and R ² represents an alkyl group having at least one fluorine atom or at least one silicon atom. ] The toner for developing an electrostatic charge image according to claim 1, wherein the polymerizable monomer A is represented by the following general formula (2).

[Wherein, R represents a substituent having 1 to 13 carbon atoms, R ³ represents an alkyl group having 1 to 8 carbon atoms, and R ⁴ represents a hydrogen atom or a substituent having 1 to 13 carbon atoms. However, R ⁴ may be the same or different from each other. R ⁵ represents an alkylene group having 1 to 8 carbon atoms. a represents 0, 1 or 2, and b is an integer of 1 to 3. However, the total value of a + b is 1-3. n represents 0 or 1. ]   The resin particles include 20% by mass to 80% by mass of the polymerization component A of the polymerizable monomer A, and 2% by mass to 20% by mass of the polymerization component B of the polymerizable monomer B. The toner for developing an electrostatic charge image according to any one of claims 1 to 3.   The volume average particle diameter of the resin particles is 30 nm to 400 nm, the softening point is 80 ° C to 170 ° C, and the Tg (glass transition temperature) is 35 ° C to 80 ° C. The toner for developing an electrostatic charge image according to 1.   The mass ratio ((s) / (s + Mp) × 100)% of the mass (s) of the resin particles and the mass (Mp) of the colored particles is 0.2% to 12%. 6. The toner for developing an electrostatic charge image according to any one of 5 above.   The electrostatic charge image developing toner according to claim 1, wherein the toner has a crushing strength index of 0.1 to 0.8. The resin particles are prepared by emulsion polymerization or miniemulsion polymerization, and at the time of the polymerization reaction, at least one compound selected from thioglycerin or a compound represented by the following general formula (3) is used as a chain transfer agent. The toner for developing an electrostatic charge image according to any one of claims 1 to 7, wherein the toner is developed through a process.
Formula ^{(3) HS-R 6 -COOR} 7
[Wherein R ⁶ represents a divalent group having 1 to 10 carbon atoms, and R ⁷ represents a hydrocarbon group having 2 to 15 carbon atoms. ] The toner contains a crystalline compound, and one or more endothermic peaks in differential thermal analysis due to the crystalline compound exist at 60 ° C. to 120 ° C., and the endothermic amount of the endothermic peak is 4 J / g to 30 J. / toner according to any one of claims 1-8, characterized in that g is. Resin particles having a polymer having a polymerization component A of a polymerizable monomer A having a silicon atom or a fluorine atom and a polymerization component B of a polymerizable monomer B having an acidic polar group, a binder resin and a colorant A step of preparing toner particles by adding metal oxide particles that have been hydrophobized to the surface of the colored particles that have been fused by the salting-out and fusing method, and the polymerization in the resin particles A method for producing a toner for developing an electrostatic charge image, wherein the polymer concentration of the polymerizable monomer A is uniform or continuously or discontinuously changes from the resin particle surface to the inside. A toner for developing an electrostatic charge image, wherein the production method according to claim 10 is used in producing the toner for developing an electrostatic charge image according to any one of claims 1 to 9. A developing roller, and a toner supply member that supplies toner for developing an electrostatic charge image on the developing roller. A nonmagnetic toner is supplied from the toner supplying member to the developing roller, and a toner layer formed on the developing roller is formed. An image forming method using a one-component developing device that performs development by using the electrostatic image developing toner according to claim 1 as the non-magnetic toner. . A latent image forming step for forming a latent image on the latent image carrier, a developing step for visualizing the latent image using toner, and a toner image formed on the latent image carrier on the transferred material 10. An image forming method comprising: a transfer step of transferring; and a fixing step of heating and fixing the toner image on the transfer target member using a heating member and a pressure member. An image forming method , wherein the heating member has an elastic layer . The image forming method according to claim 13, wherein at least one of the heating member and the pressure member is a belt .

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