JP3907314B2 - Toner for developing electrostatic image and image forming method - Google Patents

Description

【００４２】
次に、前述したＧＰＣによりトナー中のバインダー樹脂の分子量分布を測定し、バインダー樹脂のＴＨＦ可溶分を基準として分子量１，０００，０００以上のＢ成分の面積％を算出する。この際、算出した面積％が重量％と同じであると仮定し、（ＴＨＦ不溶分も含めた）全バインダー樹脂を基準とした重量％に換算する。
【００４３】
バインダー樹脂以外のトナーの構成成分でＴＨＦに可溶な成分（例えば、ＴＨＦに可溶なワックス等）が使用されている場合には、その成分の使用量及び分子量を考慮して、成分Ａ又は／及び成分Ｂからバインダー樹脂以外のＴＨＦに可溶な成分の重量を差し引いてバインダー樹脂成分中の成分Ａ及び成分Ｂの割合を求める。
【００４４】
以上の様に算出した値を全バインダー樹脂を基準とした分子量１，０００，０００以上のＢ成分の重量％とする。
【００４５】
本発明においては、前述したバインダー樹脂のＴＨＦ不溶分（Ｃ成分）が全バインダー樹脂を基準として０〜６０重量％である。これよりも多いと低温定着が低下する。ＴＨＦ不溶分が０重量％であっても、Ｂ成分が１〜２０重量％の範囲にあれば耐オフセット性、多数枚耐久性は良好となる。
【００４６】
バインダー樹脂のＢ成分及びＣ成分の合計量は１〜６０重量％であり、好ましくは５〜５８重量％であることが良い。Ｂ成分とＣ成分の合計量が１重量％よりも小さい場合には、耐高温オフセット性、耐ブロッキング性、現像性が低下し、一方、６０重量％を超える場合には、定着性が低下する。
【００４７】
該バインダー樹脂のＣ成分（ＴＨＦに不溶な樹脂成分）は、スチレンの如き単量体とジビニルベンゼンの如き架橋剤を共重合させる方法や、不飽和ポリエステルの共存下で単量体及び必要に応じて架橋剤を重合させる方法により得ることができる。
【００４８】
耐ブロッキング性、現像性の観点から、Ｂ成分及び／又はＣ成分には、ポリエステル成分が含まれることが好ましい。ポリエステル成分の含有量はＢ成分及びＣ成分の合計重量を基準にして０．０２〜９０重量％、好ましくは０．２〜８０重量％、さらに好ましくは１〜７０重量％である。０．０２重量％よりもポリエステル成分の含有量が低いと耐ブロッキング性、現像性が低下し、９０重量％を超えると現像特性が低下する。ポリエステル成分は、バインダー樹脂の重量を基準として、好ましくは０．１〜２０重量％、より好ましくは０．１〜１０重量％、最も好ましくは０．１〜５重量％含まれているのが、現像特性及び環境安定性の点で良い。Ｂ成分及びＣ成分中に含まれるポリエステル成分は、例えば以下に様にして定性及び定量することができる。
【００４９】
ＴＨＦ不溶分の分析を行なうためには、トナー粒子又はトナーを前述したＴＨＦによるソックスレー抽出をし、その後乾燥した残渣中の樹脂成分を核磁気共鳴スペクトル（¹ Ｈ−ＮＭＲ、¹³Ｃ−ＮＭＲ）、赤外吸収スペクトル（ＩＲ）、紫外吸収スペクトル（ＵＶ）、質量スペクトル（ＭＳ）等のスペクトル分析、元素分析、その他化学分析（例えば酸価、水酸基価の測定）など様々な方法により分析すればよい。ポリエステル成分の構造中に有する水酸基やカルボキシル基と反応する染料等をポリエステル成分に結合させ、可視スペクトル分析する方法なども適用することができる。これらの分析手段は単独でも複数組み合わせてもよい。
【００５０】
Ｂ成分中のポリエステル成分の定性及び定量は、例えばＧＰＣに直接ＩＲが接続されたＧＰＣ−ＩＲによる分析で行なってもよいし、例えば下記に示す分取ＨＰＬＣ装置を使ってＧＰＣの結果を正確に反映する様に条件設定し、Ｂ成分をまず分取して前記した様な分析手段で行なえば良い。
【００５１】
分取ＨＰＬＣ装置：リサイクル分取ＨＰＬＣ ＬＣ−９０８型
（日本分析工業社製）
分取カラム：ＪＡＩＧＥＬ−１Ｈ〜６Ｈ、ＪＡＩＧＥＬ−ＬＳ２０５
（日本分析工業社製）から適宜選択
分取後の試料の確認は、前述したＧＰＣの測定法に従う。
【００５２】
その他の分析手段として、分取したＢ成分を充分に乾燥した後、単独の、あるいは混合した溶媒で分別抽出し、ポリエステル成分の定量を行なう方法も採用することができる。
【００５３】
ポリエステル成分を０．０２〜９０重量％含有するＢ成分及びＣ成分は反応性ポリエステルから生成することができる。
【００５４】
反応性ポリエステルは、テレフタル酸、イソフタル酸、フタル酸、アジピン酸、マレイン酸、コハク酸、セバシン酸、チオジクリコール酸、ジクリコール酸、マロン酸、グルタン酸、ピメリン酸、スベリン酸、アゼライン酸、しょうのう酸、シクロヘキサンジカルボン酸、トリメリット酸の如き多塩基酸と；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、ネオペンチルグリコール、１，４−ビス（ヒドロキシメチル）シクロヘキサン、１，４−ビス（２−ヒドロキシエチル）ベンゼン、１，４−シクロヘキサンジメタノール、ポリエチレングリコール、ポリプロピレングリコール、ビスフェノールＡ、水素添加ビスフェノール、ビスフェノールＡのエチレンオキサイド付加物、ビスフェノールＡのプロピレンオキサイド付加物、グリセリン、トリメチロールプロパン、ペンタエリスリトールの如き多価アルコール類とを縮合重合したものが挙げられる。得られた縮合重合体（反応性ポリエステル）はその主鎖又は側鎖に反応性基を有するものである。反応性基とは、カルボン酸（又はその塩）、スルホン酸（又はその塩）、エチレンイミノ酸、エポキシ基、イソシアネート基、二重結合、酸無水物、ハロゲン原子が挙げられる。この反応性ポリエステルをお互いに反応させるか、あるいは多官能性の架橋剤（例えば多価アルコール、多塩基酸など）と反応させるか、反応性ポリエステルとビニル系単量体を反応（例えば共重合など）させることにより、Ｂ成分及びＣ成分を得ることができる。例えばモノマー組成物から重合法により直接トナー粒子を生成する場合には、反応性ポリエステルとして不飽和ポリエステルを用い、これとビニル系単量体（必要に応じてジビニルベンゼン等の架橋剤も含む）を共重合することによりＢ成分やＣ成分を得ることができる。この場合には、トナー粒子の表面（外殻）をポリエステル成分を含有するＢ成分やＣ成分で形成することが容易であり、耐ブロッキング性、耐オフセット性が特に優れたトナー粒子を得ることが可能である。
【００５５】
Ｃ成分を生成するためには、架橋剤として多官能ビニルモノマーを使用するのが好ましい。多官能ビニルモノマーとしては、例えば、ジビニルベンゼン、ジビニルナフタレンのような芳香族ジビニル化合物；エチレングリコールジアクリレート、エチレングリコールメタクリレート、１、３−ブタンジオールジメタクリレートのような二重結合を２個有するカルボン酸エステル；ジビニルアニリン、ジビニルエーテル、ジビニルスルフィド、ジビニルスルホンの如きジビニル化合物、；及び３個以上のビニル基を有する化合物が挙げられる。これらは単独もしくは混合して使用できる。
【００５６】
本発明で使用できる反応性ポルエステルは、あまり分子量が低すぎると架橋反応にあずからないポリエステルがトナー粒子表面に存在してしまうことがあり、耐ブロッキング性が低下することがある。また、あまり高分子量であると、重合法により直接トナー粒子を得る場合には、ビニル系単量体への該反応性ポリエステルの溶解が困難となるため、トナー粒子の製造が困難となる。従って、反応性ポリエステルの重量平均分子量は、３，０００〜１００，０００が特に性能の優れたトナーを得るのに好適である。反応性ポリエステルが不飽和ポリエステルの場合も、重量平均分子量（Ｍｗ）が３，０００〜１００，０００が良く、特に、ＭＷが３，０００〜３０，０００であるとビニル系単量体との反応により好ましい電子写真特性のＢ成分及びＣ成分を生成し得るので良い。
【００５７】
結着樹脂は、結着樹脂の重量を基準としてＢ成分とし成分を合計重量で５乃至５８重量％含有していることが耐高温オフセット性の向上及び耐ブロッキング性の向上の点で好ましい。より好ましくは、結着樹脂は、Ｂ成分を２〜１５重量％（さらに好ましくは、２〜１０重量％）含有し、Ｃ成分を３〜５５重量％（さらに好ましくは５〜４５重量％）含有するのが良い。又、Ｂ成分とＣ成分の合計重量が７〜４９重量％であり、結着樹脂のＴＨＦ可溶分が少なくとも５０重量％を越えていることが低温定着性及び混色性の点で好ましい。
【００５８】
ポリエステル成分が、ビニル系単量体と反応性を有する不飽和ポリエステルから生成された場合には、不飽和ポリエステルは、下記ビスフェノールＡ誘導体ユニットを有していることが電子写真特性及び定着性の点で好ましい。
【００５９】
【外４】

（式中、Ｒはエチレン又はプロピレン基であり、ｘ及びｙはそれぞれ１以上の整数であり、かつｘ＋ｙの平均値は２〜１０である）。
【００６０】
ビニル単量体と反応性を有する不飽和ポリエステルは、ビニル基（反応性の二重結合）を有するジカルボン酸として、マレイン酸、マレイン酸無水物、マレイン酸エステル、フマル酸又はフマル酸エステルと二価のアルコール成分とを縮重合して生成されたものが良く、特に、二価のアルコール成分としては下記式（Ａ）で示されるビスフェノールＡ誘導体が好ましい。
【００６１】
【外５】

（式中、Ｒはエチレン又はプロピレン基であり、ｘ及びｙはそれぞれ１以上の整数であり、かつｘ＋ｙの平均値は２〜１０である）。
【００６２】
Ａ成分、Ｂ成分やＣ成分は、それぞれ一種類の重合体に限定されるわけではない。例えば反応性ポリエステルを同時に二種以上用いることや、ビニル系重合体を二種類以上用いても良い。さらに全く種類の異なる反応性の無いポリエステル、エポキシ樹脂、ポリカーボネート、ポリオレフィン、ポリ酢酸ビニル、ポリ塩化ビニル、ポリアルキルビニルエーテル、ポリアルキルビニルケトン、ポリスチレン、ポリ（メタ）アクリルエステル、メラミンホルムアルデヒド樹脂、ポリエチレンテレフタレート、ナイロン、ポリウレタン如き重合体を必要に応じてバインダー樹脂に添加しても良い。
【００６３】
本発明においては、バインダー樹脂のＴＨＦ可溶分は、ＧＰＣの分子量分布において、分子量３，０００〜５０，０００の領域にメインピークを有している。より好ましくは、分子量３，０００〜４０，０００、最も好ましくは１０，０００〜３０，０００の領域にメインピークを有することが低温定着性、多数枚耐久性の点でより好適である。分子量が３，０００よりも小さいと高温オフセットやブロッキングを生じることがあり、分子量が５０，０００よりも大きいと低温定着が低下する。
【００６４】
また、結着樹脂のＴＨＦ可溶成分は、重量平均分子量が１００，０００以上有していることが耐高温オフセット性を向上させる上で好ましい。
【００６５】
結着樹脂は、成分Ａを結着樹脂の重量を基準にして４０〜９９重量％含有しているが、より好ましくは４２〜９５重量％、最も好ましくは５１〜９３重量％含有しているのが定着性の点で好ましい。特に、結着樹脂のＴＨＦ可溶分の重量を基準にしてＧＰＣのクロマトグラムの面積比で分子量１０００，０００以上の成分を０〜２０％（より好ましくは０．５〜１５％）、分子量５０，０００〜１０００，０００の成分を１５〜４５％（より好ましくは２０〜４０％）、分子量５０，０００以下の成分を４５〜８５％（より好ましくは５０〜７９％）有していることが、耐高温オフセット性及び低温定着性を良好に満足する点で好ましい。
【００６６】
Ａ成分はビニル系単量体から得られる重合体が７０重量％以上であり、より好ましくは７５重量％以上、さらに好ましくは８５重量％以上含有するものであり、この範囲内であればポリエステルの如き他の重合体を含有していてもよいが、ビニル系単量体から得られる重合体の含有量が７０重量％未満となると環境安定性、低温定着性が低下するため好ましくない。
【００６７】
Ａ成分中の重合体の定性、定量は、前述したポリエステル成分の分析方法と同様にして行なえば良い。
【００６８】
本発明においては、離型剤としてワックスを含有している。
【００６９】
本発明に用いられるワックスとしては、例えばパラフィンワックス及びその誘導体、マイクロクリスタリンワックス、及びその誘導体、フィッシャートロプシュワックス及びその誘導体、ポリオレフィンワックス及びその誘導体、カルナバワックス及びその誘導体などで、誘導体には酸化物や、ビニル系モノマーとのブロック共重合物、グラフト変性物を含む。その他、高級脂肪酸およびその金属塩、高級脂肪族アルコール、高級脂肪族エステル、脂肪族アミドワックス、ケトン、硬化ヒマシ油及びその誘導体、植物系ワックス、動物性ワックス、鉱物系ワックス、ペトロラクタムが挙げられる。
【００７０】
これらのワックスは、示差走差熱量計により測定されるＤＳＣ吸熱曲線において、昇温時に４０〜１５０℃の領域に吸熱メインピークを有することが好ましい。上記温度領域に吸熱メインピークを有することにより、低温定着に大きく貢献しつつ、離型性をも効果的に発現する。該最大吸熱ピークが４０℃未満であるとワックスの自己凝集力が弱くなり、結果として耐高温オフセット性が低下するとともに、グロスが高くなりすぎる。一方、該最大吸熱ピークが１５０℃を越えると定着温度が高くなるとともに、定着画像表面を適度に平滑化せしめることが困難となる。特にカラートナーに用いた場合には混色性低下の点から好ましくない。さらに、水系媒体中で造粒／重合を行ない重合方法により直接トナーを得る場合、該最大吸熱ピーク温度が高いと主に造粒中にワックス成分が析出する等の問題を生じ好ましくない。
【００７１】
ワックス成分の最大吸熱ピーク温度の測定は、「ＡＳＴＭ Ｄ ３４１８−８」に準じて行なう。測定には、例えばパーキンエルマー社製ＤＳＣ−７を用いる。装置検出部の温度補正はインジウムと亜鉛の融点を用い、熱量の補正についてはインジウムの融解熱を用いる。測定サンプルにはアルミニウム製のパンを用い、対照用に空パンをセットし、昇温速度１０℃／ｍｉｎで測定を行なう。
【００７２】
より好ましくは、ワックスは、ＤＳＣ吸熱曲線において、温度４５〜１４５℃（最も好ましくは、５０〜１００℃）に吸熱メインピークを有することが好ましい。特にカラートナーの場合は、吸熱メインピークが５０〜１００℃にあるのが混色性及び耐オフセット性の点で良い。
【００７３】
本発明においては、これらのワックス成分の添加量は特に限定されないが、一般にトナーに対して２〜３０重量％（より好ましくは３〜２５重量％）が好ましい。
【００７４】
ワックスには、トナーの帯電性に影響を与えない範囲で酸化防止剤が添加されていても良い。
【００７５】
本発明のトナーに使用されるトナー粒子は、透過電子顕微鏡（ＴＥＭ）を用いた断層面観察において、表面がポリエステル成分を含有するバインダー樹脂で形成されており、その内部にビニル単量体から得られるバインダー樹脂とワックスが存在し、ワックスがバインダー樹脂と相溶しない状態で、図２に示す如く実質的に球状及び／又は紡錘形で島状に分散されている構造を有していることが好ましい。バインダー樹脂中にワックスを内包化し、かつ、表面をポリエステル成分を含有するバインダー樹脂で形成することにより、多量のワックスをトナー粒子が含有していても、トナーの劣化や画像形成装置への汚染を防止することができるので、良好な摩擦帯電性が維持され、デジタル潜像を忠実に現像したトナー画像を長期にわたって形成することが可能である。また、加熱加圧時には多量のワックスが効率良く作用するため、低温定着性と耐オフセット性を満足なものとする。
【００７６】
トナー粒子の断層面を測定する具体的方法としては、常温硬化性のエポキシ樹脂中にトナー粒子を十分分散させた後、温度４０℃の雰囲気中で２日間硬化させる。得られた硬化物を四三酸化ルテニウム、必要により四三酸化オスミウムを併用し染色を施した後、ダイヤモンド歯を備えたミクロトームを用い薄片状のサンプルを切り出し透過電子顕微鏡（ＴＥＭ）を用いたトナー粒子の断層形態を測定する。ワックスをコアとし、バインダー樹脂を外殻とする構造は、ワックスと樹脂との若干の結晶化度の違いを利用して材料間のコントラストを付けるため四三酸化ルテニウム染色法を用いる。後記の実施例で得られたトナー粒子をＴＥＭにて断層面観察したところ、図２（ａ）の如くワックスがバインダー樹脂中に球状（及び／又は紡錘形）で島状に存在していた。
【００７７】
本発明に使用するトナー粒子は、画像解析装置で測定した形状係数ＳＦ−１の値が１００〜１６０（好ましくは、１００〜１４０）であり、形状係数ＳＦ−２の値が１００〜１４０（好ましくは、１００〜１２０）である。
【００７８】
本発明において、トナー粒子の形状係数を示すＳＦ−１とは、例えば日立製作所製ＦＥ−ＳＥＭ（Ｓ−８００）を用いた倍率５００倍に拡大したトナー像を１００個無作為にサンプリングし、その画像情報はインターフェースを介して例えばニコレ社製画像解析装置（Ｌｕｚｅｘ ＩＩＩ）を導入し解析を行ない、下式より算出し得られた値を形状係数ＳＦ−１と定義する。
【００７９】
【外６】

〔式中、ＭＸＬＮＧはトナー粒子の絶対最大長を示し、ＡＲＥＡはトナー粒子の投影面積を示す〕。
【００８０】
さらに、形状係数ＳＦ−２は、下記式より算出して得られた値をいう。
【００８１】
【外７】

〔式中、ＰＥＲＩは、トナー粒子の周長を示し、ＡＲＥＡはトナー粒子の投影面積を示す〕。
【００８２】
形状係数ＳＦ−１は、トナー粒子の丸さの度合を示し、形状係数ＳＦ−２は、トナー粒子の凹凸の度合を示している。
【００８３】
従来、トナー粒子の形状係数ＳＦ−１やＳＦ−２が小さくなった場合、クリーニング不良が発生し易くなったり、また、長期間使用した際に外添剤がトナー粒子表面に埋没し易くなったりし、結果的に画質の劣化を招くことが多かった。本発明においてはトナー粒子表面をポリエステル成分を含有するＢ成分及び／又はＣ成分で形成することによりトナー粒子に適度な強度を与えているので、これらの問題を未然に防止することができる。
【００８４】
形状係数ＳＦ−１が１６０を超える場合、トナー粒子の形状が不定形となる為、トナーの帯電分布がブロードになると共に、現像器内でトナー粒子表面が磨砕され易くなる為、画像濃度低下や画像カブリの一因となる。また、画像形成装置に中間転写体を用いる場合、静電荷像担持体から中間転写体への転写時におけるトナー像の転写効率の低下が認められ、さらに、中間転写体から転写材への転写時におけるトナー像の転写効率の低下も認められる。
【００８５】
トナー像の転写効率を高めるためには、トナー粒子の形状係数ＳＦ−２は、１００〜１４０であり、さらに好ましくは（ＳＦ−２）／（ＳＦ−１）の値が１．０以下であるのが良い。トナー粒子の形状係数ＳＦ−２が１４０を超え（ＳＦ−２）／（ＳＦ−１）の値が１．０を超える場合、トナー粒子の表面が滑らかではなく、多数の凹凸をトナー粒子が有しており、静電荷像担持体から中間転写体への転写時及び中間転写体から転写材への転写時に転写効率が低下する傾向にある。
【００８６】
トナー粒子に外添剤が外添されているトナーの形状係数ＳＦ−１及びＳＦ−２を測定しても、外添剤の粒径が非常に小さいか、または粒径の粗い外添剤が存在したとしてもトナー粒子の個数と比較して非常に少ないために、トナー粒子の形状係数ＳＦ−１及びＳＦ−２と実質的に相違しないものである。
【００８７】
多種の転写材に対応させるために、中間転写体を使用する場合、転写工程が２回行なわれるため、転写効率の低下はトナーの利用効率の低下を招きやすい。デジタルフルカラー複写機やデジタルフルカラープリンターにおいては、色画像原稿を予めＢ（ブルー）フィルター、Ｇ（グリーン）フィルター、Ｒ（レッド）フィルターを用い色分解した後、感光体上に２０〜７０μｍのドット潜像を形成しＹ（イエロー）トナー、Ｍ（マゼンタ）トナー、Ｃ（シアン）トナー、Ｂ（ブラック）トナーの各色トナーを用いで原色混合作用を利用し原稿に忠実な多色カラー画像を再現する必要がある。この際、感光体上又は中間転写体上には、Ｙトナー、Ｍトナー、Ｃトナー、Ｂトナーが原稿やＣＲＴの色情報に対応して多量にトナーが乗るため各カラートナーは、極めて高い転写性が要求される。それを実現させる為にはトナー粒子の形状係数ＳＦ−１及びＳＦ−２が上記条件を満足しているトナー粒子が好ましい。
【００８８】
更に高画質化のため微小な潜像ドットを忠実に現像するために、トナー粒子は、重量平均径が４〜９μｍ（より好ましくは、４μｍ〜８μｍ）であり、個数分布における変動係数が３５％以下であることが好ましい。重量平均径が４μｍ未満のトナー粒子においては、転写効率の低下から感光体や中間転写体上に転写残のトナー粒子が多く、さらに、カブリ、転写不良に基づく画像の不均一ムラの原因となりやすい。トナー粒子の重量平均径が９μｍを超える場合には、感光体表面、中間転写材の部材への融着が起きやすい。トナー粒子の個数分布における変動係数が３５％を超えると更にその傾向が強まる。
【００８９】
トナー粒子の粒度分布は種々の方法によって測定できる。例えばコールターカウンター法を用いて行なう。
【００９０】
例えば、測定装置としてはコールターカウンターＴＡ−ＩＩ型又はコールターマルチサイザー（コールター社製）を用い、個数分布及び体積分布を出力するインターフェイス（日科機製）及びパーソナルコンピュータを接続し、電解液は１級塩化ナトリウムを用いて約１％ＮａＣｌ水溶液を調製する。例えばＩＳＯＴＯＮ ＩＩ（コールターサイエンティフィックジャパン社製）が使用できる。測定法としては前記電解水溶液１００〜１５０ｍｌ中に分散剤として界面活性剤（好ましくはアルキルベンゼンスルホン酸塩）を０．１〜５ｍｌ加え、更に測定試料を２〜２０ｍｇ加える。試料を懸濁した電解液は超音波分散器で約１〜３分間分散処理を行ない、前記測定装置により、アパチャーとして例えば１００μｍアパチャーを用い、個数を基準として２〜４０μｍの粒子の粒度分布を測定して、それから本発明に係る値を求める。
【００９１】
トナー粒子の個数分布における変動係数は下記式から算出される。
【００９２】
変動係数＝〔Ｓ／Ｄ₁ 〕×１００
〔式中、Ｓは、トナー粒子の個数分布における標準偏差値を示し、Ｄ₁ は、トナー粒子の個数平均粒径（μｍ）を示す〕。
【００９３】
外添剤が混合されているトナーを測定しても、粒径２μｍ以上の外添剤の重量及び個数がトナー粒子よりも非常に少ないため、トナー粒子と実質に同じ値を示す。
【００９４】
本発明に用いられる着色剤は、以下に示すイエロー着色剤、マゼンタ着色剤及びシアン着色剤が挙げられ、黒色着色剤としてカーボンブラック、磁性体または以下に示すイエロー着色剤／マゼンタ着色剤／シアン着色剤を混合して黒色に調色されたものが利用される。
【００９５】
イエロー着色剤としては、縮合アゾ化合物，イソインドリノン化合物，アンスラキノン化合物，アゾ金属錯体，メチン化合物，アリルアミド化合物に代表される化合物が用いられる。具体的には、Ｃ．Ｉ．ピグメントイエロー１２、１３、１４、１５、１７、６２、７４、８３、９３、９４、９５、１０９、１１０、１１１、１２８、１２９、１４７、１６８、１８０等が好適に用いられる。
【００９６】
マゼンタ着色剤としては、縮合アゾ化合物，ジケトピロロピロール化合物，アンスラキノン，キナクリドン化合物，塩基染料レーキ化合物，ナフトール化合物，ベンズイミダゾロン化合物，チオインジゴ化合物，ペリレン化合物が用いられる。具体的には、Ｃ．Ｉ．ピグメントレッド２、３、５、６、７、２３、４８；２、４８；３、４８；４、５７；１、８１；１、１４４、１４６、１６６、１６９、１７７、１８４、１８５、２０２、２０６、２２０、２２１、２５４が特に好ましい。
【００９７】
シアン着色剤としては、銅フタロシアニン化合物及びその誘導体，アンスラキノン化合物，塩基染料レーキ化合物等が利用できる。具体的には、Ｃ．Ｉ．ピグメントブルー１、７、１５、１５：１、１５：２、１５：３、１５：４、６０、６２、６６等が好適に利用できる。
【００９８】
これらの着色剤は、単独又は混合し更には固溶体の状態で用いることができる。着色剤は、色相，彩度，明度，耐候性，ＯＨＰ透明性，トナー粒子中への分散性の点から選択される。該着色剤の添加量は、結着樹脂１００重量部に対し１〜２０重量部使用するのが好ましい。
【００９９】
黒色着色剤として磁性体を用いた場合には、他の着色剤と異なり、結着樹脂１００重量部に対し４０〜１５０重量部使用するのが好ましい。
【０１００】
本発明のトナーには荷電制御剤を使用しても良い。荷電制御剤としては公知のものが利用でき、特に帯電スピードが速く、且つ、一定の帯電量を安定して維持できる荷電制御剤が好ましい。更に、トナー粒子を直接重合法を用いる場合には、重合阻害性が無く水系分散媒体への可溶化物の無い荷電制御剤が特に好ましい。具体的化合物としては、ネガ系荷電制御剤としてサリチル酸、アルキルサリチル酸、ジアルキルサリチル酸、ナフトエ酸、ダイカルボン酸の如き芳香族カルボン酸の金属化合物；スルホン酸又はカルボン酸基を側鎖に持つ高分子型化合物；ホウ素化合物；尿素化合物；ケイ素化合物；カリークスアレーン等が挙げられる。ポジ系荷電制御剤として、四級アンモニウム塩；該四級アンモニウム塩を側鎖に有する高分子型化合物；グアニジン化合物；イミダゾール化合物等が挙げられる。該荷電制御剤は樹脂１００重量部に対し０．５〜１０重量部使用することが好ましい。しかしながら、本発明において荷電制御剤の添加は必須ではなく、二成分現像方法を用いた場合においては、キャリヤーとの摩擦帯電を利用し、非磁性一成分ブレードコーティング現像方法を用いた場合においては、ブレード部材やスリーブ部材との摩擦帯電を積極的に利用することでトナー粒子中に必ずしも荷電制御剤を含む必要はない。
【０１０１】
本発明のトナーを製造する方法としては、樹脂，低軟化点物質からなる離型剤（ワックス），着色剤，荷電制御剤等を加圧ニーダーやエクストルーダー又はメディア分散機を用い均一に分散せしめた後、機械的又はジェット気流下でターゲットに衝突させ、所望のトナー粒径に微粉砕化せしめた後（必要により、トナー粒子の平滑化及び球形化の工程を付加）、更に分級工程を経て粒度分布をシャープにせしめトナーにする粉砕方法によるトナーの製造方法の他に、特公昭５６−１３９４５号公報等に記載のディスク又は多流体ノズルを用い溶融混合物を空気中に霧化し球状トナーを得る方法や、特公昭３６−１０２３１号公報、特開昭５９−５３８５６号公報、特開昭５９−６１８４２号公報に述べられている懸濁重合方法を用いて直接トナーを生成する方法や、単量体には可溶で得られる重合体が不溶な水系有機溶剤を用い直接トナーを生成する分散重合方法又は水溶性極性重合開始剤存在下で直接重合しトナーを生成するソープフリー重合法に代表される乳化重合方法等を用いトナーを製造することが可能である。
【０１０２】
粉砕法を用いトナーを製造する方法においては、ルーゼックスで測定したトナーの形状係数であるＳＦ−１やＳＦ−２を所望の範囲に納めることが困難であり、溶融スプレー法においては、ＳＦ−１値を１００〜１６０に納めることが出来ても、得られたトナー粒子の粒度分布が広くなりやすい。他方、分散重合法においては、得られるトナーは極めてシャープな粒度分布を示すが、使用する材料の選択が狭いことや有機溶剤の利用が廃溶剤の処理や溶剤の引火性に関する観点から製造装置が複雑で煩雑化しやすい。ソープフリー重合に代表される乳化重合方法は、トナーの粒度分布が比較的揃うため有効であるが、使用した乳化剤や重合開始剤末端がトナー粒子表面に存在し時に環境特性を低下させやすい。
【０１０３】
本発明においてはトナーの形状係数ＳＦ−１値を１００〜１６０にコントロールでき、比較的容易に粒度分布がシャープで４〜９μｍ粒径のトナー粒子が得られる常圧下、または、加圧下での乳化重合法又は懸濁重合方法を用い、予め得られた重合体にメディアを用い定形化したり、直接加圧衝突板に重合体を衝突せしめる方法や、更には得られた重合体を水系媒体中にて凍結せしめたり、塩折や反対表面電荷を有する粒子をｐＨ等の条件を考慮することで合体し、凝集及び合一せしめても良い。さらに、一旦得られた重合粒子に更に単量体を吸着せしめた後、重合開始剤を用い重合せしめるシード重合方法を用いても良い。
【０１０４】
トナー粒子の製造方法として水系媒体中で重合性単量組成物の粒子を重合する直接重合方法を使用する場合、トナー粒子の粒度分布制御や粒径の制御は、難水溶性の無機塩や保護コロイド作用をする分散剤の種類や添加量を変える方法や機械的装置条件（例えばローターの周速、パス回数、攪拌羽根形状等の攪拌条件や容器形状）又は、水溶液中での固形分濃度を制御することにより所定のトナー粒子を得ることができる。
【０１０５】
直接重合法によりトナー粒子を製造する際、用いられる重合開始剤としては例えば、２，２′−アゾビス−（２，４−ジメチルバレロニトリル）、２，２′−アゾビスイソブチロニトリル、１，１′−アゾビス（シクロヘキサン−１−カルボニトリル）、２，２′−アゾビス−４−メトキシ−２，４−ジメチルバレロニトリル、アゾビスイソブチロニトリルの如きアゾ系又はアゾビス系重合開始剤；ベンゾイルペルオキシド、メチルエチルケトンペルオキシド、ジイソプロピルペルオキシカーボネート、クメンヒドロペルオキシド、２，４−ジクロロベンゾイルペルオキシド、ラウロイルペルオキシドの如き過酸化物系重合開始剤が用いられる。該重合開始剤の使用量は、目的とする重合度により変化するが一般的には重合性単量体に対し０．５〜２０重量％用いられる。重合開始剤の種類は、重合法により若干異なるが、十時間半減期温度を参考に、単独又は混合して使用される。
【０１０６】
重合度を制御するため公知の架橋剤，連鎖移動剤，重合禁止剤等を更に添加し用いても良い。
【０１０７】
トナー粒子の製法として分散安定剤を用いた懸濁重合法を利用する場合、用いる分散安定剤としては、無機化合物として、リン酸三カルシウム，リン酸マグネシウム，リン酸アルミニウム，リン酸亜鉛，炭酸カルシウム，炭酸マグネシウム，水酸化カルシウム，水酸化マグネシウム，水酸化アルミニウム，メタケイ酸カルシウム，硫酸カルシウム，硫酸バリウム，ベントナイト，シリカ，アルミナ等が挙げられる。有機化合物としては、ポリビニルアルコール，ゼラチン，メチルセルロース，メチルヒドロキシプロピルセルロース，エチルセルロース，カルボキシメチルセルロースのナトリウム塩，ポリアクリル酸及びその塩，デンプン等が挙げられる。これらを水相に分散させて使用できる。これら分散安定剤は、重合性単量体１００重量部に対して０．２〜２０重量部を使用することが好ましい。
【０１０８】
分散安定剤として、無機化合物を用いる場合、市販のものをそのまま用いても良いが、細かい粒子を得るために、分散媒体中にて該無機化合物の微粒子を生成しても良い。例えば、リン酸三カルシウムの場合、高速攪拌下において、リン酸ナトリウム水溶液と塩化カルシウム水溶液を混合すると良い。
【０１０９】
これら分散安定剤の微細な分散の為に、０．００１〜０．１重量部の界面活性剤を併用してもよい。これは上記分散安定剤の所期の作用を促進するためのものであり、例えば、ドデシルベンゼン硫酸ナトリウム，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，オレイン酸ナトリウム，ラウリル酸ナトリウム，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。
【０１１０】
本発明で使用するトナーの製造方法として直接重合法を用いる場合においては、以下の如き製造方法が可能である。
【０１１１】
ビニル系単量体中に、着色剤、反応性エステル及びワックス、必要により荷電制御剤、重合開始剤その他の添加剤を加え、ホモジナイザー、超音波分散機等によって均一に溶解又は分散せしめた重合性単量体組成物を、分散安定剤を含有する水系媒体中に通常の攪拌機またはホモミキサー，ホモジナイザー等により分散せしめる。好ましくは重合性単量体組成物の液滴が所望のトナー粒子のサイズを有するように攪拌速度，攪拌時間を調整し、造粒する。その後は分散安定剤の作用により、粒子状態が維持され、且つ粒子の沈降が防止される程度の攪拌を行えば良い。重合温度は４０℃以上、一般的には５０〜９０℃の温度に設定して重合を行うのが良い。重合反応後半に昇温しても良く、更に、本発明における画像形成方法における耐久性向上の目的で、未反応の重合性単量体、副生成物等を除去するために反応後半、又は、反応終了後に一部水系媒体を反応系から留去しても良い。反応終了後、生成したトナー粒子を洗浄・濾過により回収し、乾燥する。懸濁重合法においては、通常単量体組成物１００重量部に対して水３００〜３０００重量部を分散媒体として使用するのが好ましい。
【０１１２】
所定の割合の成分Ａ、成分Ｂ及び成分Ｃをトナー粒子間のバラツキを少なく含有させるためには、トナー粒子は、ビニル系単量体、不飽和ポリエステル、着色剤及びワックスを少なくとも含有する重合性単量体組成物を水系媒体中に分散して、重合性単量体組成物の粒子を生成し、水系媒体中で重合性単量体組成物中のビニル系単量体を重合してトナー粒子を生成するのが良い。ビニル系単量体としては、スチレンモノマー，アクリル酸エステル又はメタクリル酸エステルが好ましく、特に、ガラス転移点が４０〜７５℃となるようにスチレンモノマーとアクリル酸エステル又は／及びメタクリル酸エステルとを組み合わせて使用するのが良い。
【０１１３】
重合性単量体組成物中の不飽和ポリエステルは、カルボキシル基及びヒドロキシル基を有しているので水系媒体中の重合性単量体組成物の粒子の表面に偏在する傾向がある。粒子の表面に偏在した不飽和ポリエステルはビニル系単量体と反応して成分Ｂ及び成分Ｃを生成し、トナー粒子表面を分子量１００万以上の成分Ｂ及び／又はＴＨＦに不溶な程高分子量化した成分Ｃで形成し、トナー粒子の内部をワックスを内包している成分Ａで形成することができる。そのため耐摩擦性、耐衝撃性に強く、多数耐久性に優れ、耐高温オフセット性及び低温定着性に優れているトナー粒子を効率良く生成することができる。成分Ｂ及び成分Ｃの比率を調整するために重合性単量体組成物は、ジビニルベンゼンの如き架橋剤をビニル単量体１００重量部に対し０．０１〜２．５重量部、より好ましくは、０．０５〜１．０重量部使用するのも好ましい。この様にして生成されたトナー粒子においては、ビニル重合体と、ビニル重合体ユニットとポリエステルユニットとが結合したハイブリット成分をトナー粒子表面に偏在させることが可能である。トナー粒子表面にハイブリット成分を偏在させるために、不飽和ポリエステルは重量平均分子量が３０００〜１０万（より好ましくは、３０００〜３万）であることが良く、酸価が２〜２０ｍｇＫＯＨ／ｇであるのが良く、また、直鎖状のポリエステルであるのが好ましい。
【０１１４】
トナー粒子には、ＢＥＴ比表面積５０〜４００ｍ² ／ｇの疎水性シリカ微粉体、疎水性酸化チタン微粉体又は疎水性アルミナ微粉体がトナー粒子１００重量部に対して、０．１〜４．０重量部外添されていることが、流動性、環境安定性を向上させる点で好ましい。
【０１１５】
次に本発明のトナーが適用される画像形成方法を添付図面を参照しながら以下に説明する。
【０１１６】
図３に示す装置システムにおいて、現像器４−１、４−２、４−３、４−４に、それぞれシアントナーを有する現像剤、マゼンタトナーを有する現像剤、イエロートナーを有する現像剤及びブラックトナーを有する現像剤が導入され、磁気ブラシ現像方式又は非磁性一成分方式によって静電荷像担持体（例えば感光体ドラム）１に形成された静電荷像を現像し、各色トナー像が感光体ドラム１上に形成される。
【０１１７】
本発明のトナーは、磁性キャリアと混合し、例えば図４に示すような現像手段を用い現像を行うことができる。具体的には交番電界を印加しつつ、磁気ブラシが感光体ドラム１３に接触している状態で現像を行うことが好ましい。現像剤担持体（現像スリーブ）１１と感光体ドラム１３の距離（Ｓ−Ｄ間距離）Ｂは１００〜１０００μｍであることがキャリア付着防止及びドット再現性の向上において良好である。１００μｍより狭いと現像剤の供給が不十分になりやすく、画像濃度が低くなり、１０００μｍを超えると磁石Ｓ１からの磁力線が広がり磁気ブラシの密度が低くなり、ドット再現性に劣ったり、キャリアを拘束する力が弱まりキャリア付着が生じやすくなる。
【０１１８】
交番電界のピーク間の電圧（Ｖｐｐ）は５００〜５０００Ｖが好ましく、周波数（ｆ）は５００〜１００００Ｈｚ、好ましくは５００〜３０００Ｈｚであり、それぞれプロセスに適宜選択して用いることができる。この場合、波形としては三角波、矩形波、正弦波、あるいはＤｕｔｙ比を変えた波形等種々選択して用いることができる。印加電圧が、５００Ｖより低いと十分な画像濃度が得られにくく、また非画像部のカブリトナーを良好に回収することができない場合がある。５００００Ｖを超える場合には磁気ブラシを介して、静電像を乱してしまい、画質低下を招く場合がある。
【０１１９】
良好に帯電したトナーを有する二成分系現像剤を使用することで、カブリ取り電圧（Ｖｂａｃｋ）を低くすることができ、感光体の一次帯電を低めることができるために感光体寿命を長寿命化できる。Ｖｂａｃｋは、現像システムにもよるが１５０Ｖ以下、より好ましくは１００Ｖ以下が良い。
【０１２０】
コントラスト電位としては、十分画像濃度がでるように２００Ｖ〜５００Ｖが好ましく用いられる。
【０１２１】
周波数が５００Ｈｚより低いとプロセススピードにも関係するが、キャリアへの電荷注入が起こるためにキャリア付着、あるいは潜像を乱すことで画質を低下させる場合がある。１００００Ｈｚを超えると電界に対してトナーが追随できず画質低下を招きやすい。
【０１２２】
十分な画像濃度を出し、ドット再現性に優れ、かつキャリア付着のない現像を行うために現像スリーブ１１上の磁気ブラシの感光体ドラム１３との接触幅（現像ニップＣ）を好ましくは３〜８ｍｍにすることである。現像ニップＣが３ｍｍより狭いと十分な画像濃度とドット再現性を良好に満足することが困難であり、８ｍｍより広いと、現像剤のパッキングが起き機械の動作を止めてしまったり、またキャリア付着を十分に抑さえることが困難になる。現像ニップの調整方法としては、現像剤規制部材１８と現像スリーブ１１との距離Ａを調整したり、現像スリーブ１１と感光体ドラム１３との距離Ｂを調整することでニップ幅を適宜調整する。
【０１２３】
特にハーフトーンを重視するようなフルカラー画像の出力において、マゼンタ用、シアン用、及びイエロー用の３個以上の現像器が使用され、本発明の現像剤及び現像方法を用い、特にデジタル潜像を形成した現像システムと組み合わせることで、磁気ブラシの影響がなく、潜像を乱さないためにドット潜像に対して忠実に現像することが可能となる。転写工程においても本発明トナーを用いることで高転写率が達成でき、したがって、ハーフトーン部、ベタ部共に高画質を達成できる。
【０１２４】
さらに初期の高画質化と併せて、本発明のトナーを用いることで多数枚の複写においても画質低下のない本発明の効果が十分に発揮できる。
【０１２５】
本発明のトナーは一成分現像にも好適に用いることが出来る。静電荷像担持体上に形成された静電像を現像する装置の一例を示すが必ずしもこれに限定されるものではない。
【０１２６】
図５において、２５は静電荷像担持体（感光体ドラム）であり、潜像形成は電子写真プロセス手段又は静電記録手段により形成される。２４はトナー担持体（現像スリーブ）であり、アルミニウムあるいはステンレス等からなる非磁性スリーブからなる。
【０１２７】
現像スリーブ２４の略右半周面はトナー容器２１内のトナー溜りに常時接触していて、その現像スリーブ面近傍のトナーが現像スリーブ面にスリーブ内の磁気発生手段の磁力で及び／又は静電気力により付着保持される。
【０１２８】
本発明では、トナー担持体の表面粗度Ｒａ（μｍ）を１．５以下となるように設定する。好ましくは１．０以下である。更に好ましくは０．５以下である。
【０１２９】
該表面粗度Ｒａを１．５以下とすることでトナー担持体の有するトナー粒子の搬送能力を抑制し、該トナー担持体上のトナー層を薄層化すると共に、該トナー担持体とトナーの接触回数が多くなる為、該トナーの帯電性も改善されるので相乗的に画質が向上する。
【０１３０】
該トナー担持体の表面粗度Ｒａが１．５を超えると、該トナー担持体上のトナー層の薄層化が困難となるばかりか、トナーの帯電性が改善されないので画質の向上は望めない。
【０１３１】
本発明において、トナー担持体の表面粗度Ｒａは、ＪＩＳ表面粗さ「ＪＩＳ Ｂ ０６０１」に基づき、表面粗さ測定器（サーフコーダＳＥ−３０Ｈ、株式会社小坂研究所社製）を用いて測定される中心線平均粗さに相当する。具体的には、粗さ曲線からその中心線の方向に測定長さａとして２．５ｍｍの部分を抜き取り、この抜き取り部分の中心線をＸ軸、縦倍率の方向をＹ軸、粗さ曲線をｙ＝ｆ（ｘ）で表わした時、次式によって求められる値をミクロメートル（μｍ）で表わしたものをいう。
【０１３２】
【外８】

【０１３３】
本発明に用いられるトナー担持体としては、たとえばステンレス，アルミニウム等から成る円筒状、あるいはベルト状部材が好ましく用いられる。また必要に応じ表面を金属，樹脂等のコートをしても良く、樹脂や金属類，カーボンブラック，帯電制御剤等の微粒子を分散した樹脂をコートしても良い。
【０１３４】
本発明では、トナー担持体の表面移動速度を静電荷像担持体の表面移動速度に対し１．０５〜３．０倍となるように設定することで、該トナー担持体上のトナー層は適度な撹拌効果を受ける為、静電潜像の忠実再現が一層良好なものとなる。
【０１３５】
該トナー担持体の表面移動速度が、静電潜像担持体の表面移動速度に対し１．０５倍未満であると、該トナー層の受ける攪拌効果が不十分となり、良好な画像形成は望めない。また、ベタ黒画像等、広い面積にわたって多くのトナー量を必要とする画像を現像する場合、静電潜像へのトナー供給量が不足し画像濃度が薄くなる。逆に３．０を超える場合、上記の如きトナーの過剰な帯電によって引き起こされる種々の問題の他に、機械的ストレスによるトナーの劣化やトナー担持体へのトナー固着が発生、促進され、好ましくない。
【０１３６】
トナーＴはホッパー２１に貯蔵されており、供給部材２２によって現像スリーブ上へ供給される。供給部材として、多孔質弾性体、例えば軟質ポリウレタンフォーム等の発泡材より成る供給ローラーが好ましく用いられる。該供給ローラーを現像スリーブに対して、順または逆方向に０でない相対速度をもって回転させ、現像スリーブ上へのトナー供給と共に、スリーブ上の現像後のトナー（未現像トナー）のはぎ取りをも行う。この際、供給ローラーの現像スリーブへの当接幅は、トナーの供給及びはぎ取りのバランスを考慮すると、２．０〜１０．０ｍｍが好ましく、４．０〜６．０ｍｍがより好ましい。その一方で、トナーに対する過大なストレスを余儀なくされ、トナーの劣化による凝集の増大、あるいは現像スリーブ，供給ローラー等へトナーの融着・固着が生じやすくなるが、本発明の現像法に用いられるトナーは、流動性，離型性に優れ、耐久安定性を有しているので、該供給部材を有する現像法においても好ましく用いられる。また、供給部材として、ナイロン，レーヨン等の樹脂繊維より成るブラシ部材を用いてもよい。これらの供給部材は磁気拘束力を利用できない非磁性一成分トナーを使用する一成分現像方法において極めて有効であるが、磁性一成分トナーを使用する一成分現像方法に使用してもよい。
【０１３７】
現像スリーブ上に供給されたトナーは規制部材によって薄層かつ均一に塗布される。トナー薄層化規制部材は、現像スリーブと一定の間隙をおいて配置される金属ブレード、磁性ブレード等のドクターブレードである。あるいは、ドクターブレードの代りに、金属，樹脂，セラミックなどを用いた剛体ローラーやスリーブを用いても良く、それらの内部に磁気発生手段を入れても良い。
【０１３８】
また、トナー薄層化の規制部材としてトナーを圧接塗布する為の弾性ブレードや弾性ローラーの如き弾性体を用いても良い。例えば図５において、弾性ブレード２３はその上辺部側である基部を現像剤容器２１側に固定保持され、下辺部側をブレードの弾性に抗して現像スリーブ２４の順方向或いは逆方向にたわめ状態にしてブレード内面側（逆方向の場合には外面側）をスリーブ２４表面に適度の弾性押圧をもって当接させる。この様な装置によると、環境の変動に対しても安定で、緻密なトナー層が得られる。その理由は必ずしも明確ではないが、該弾性体によって現像スリーブ表面と強制的に摩擦される為トナーの環境変化による挙動の変化に関係なく常に同じ状態で帯電が行われる為と推測される。
【０１３９】
その一方で帯電が過剰になり易く、現像スリーブや弾性ブレード上にトナーが融着し易いが、本発明に用いられるトナーは離型性に摩擦帯電性が安定しているので好ましく用いられる。
【０１４０】
該弾性体には所望の極性にトナーを帯電させるのに適した摩擦帯電系列の材質を選択することが好ましく、シリコーンゴム，ウレタンゴム，ＮＢＲの如きゴム弾性体；ポリエチレンテレフタレートの如き合成樹脂弾性体；ステンレス，鋼，リン青銅の如き金属弾性体が使用できる。また、それらの複合体であっても良い。
【０１４１】
また、弾性体とトナー担持体に耐久性が要求される場合には、金属弾性体に樹脂やゴムをスリーブ当接部に当るように貼り合わせたり、コーティング塗布したものが好ましい。
【０１４２】
更に、弾性体中に有機物や無機物を添加しても良く、溶融混合させても良いし、分散させても良い。例えば、金属酸化物、金属粉、セラミックス、炭素同素体、ウィスカー、無機繊維、染料、顔料、界面活性剤などを添加することにより、トナーの帯電性をコントロールできる。特に、弾性体がゴムや樹脂等の成型体の場合には、シリカ、アルミナ、チタニア、酸化錫、酸化ジルコニア、酸化亜鉛等の金属酸化物微粉末、カーボンブラック、一般にトナーに用いられる荷電制御剤等を含有させることも好ましい。
【０１４３】
またさらに、規制部材である現像ブレード、供給部材である供給ローラー、ブラシ部材に直流電場及び／または交流電場を印加することによっても、トナーへのほぐし作用のため現像スリーブ上の規制部材においては、均一薄層塗布性、均一帯電性がより向上し、供給部位においては、トナーの供給／はぎとりがよりスムーズになされ、十分な画像濃度の達成及び良質の画像を得ることができる。
【０１４４】
該弾性体とトナー担持体との当接圧力は、トナー担持体の母線方向の線圧として、０．１ｋｇ／ｍ以上、好ましくは０．３〜２５ｋｇ／ｍ、更に好ましくは０．５〜１２ｋｇ／ｍが有効である。これによりトナーの凝集を効果的にほぐすことが可能となり、トナーの帯電量を瞬時に立ち上げることが可能になる。当接圧力が０．１ｋｇ／ｍより小さい場合、トナーの均一塗布が困難となり、トナーの帯電量分布がブロードになりカブリや飛散の原因となる。また当接圧力が２５ｋｇ／ｍを超えると、トナーに大きな圧力がかかり、トナーが劣化したり、トナーの凝集物が発生するなど好ましくない。またトナー担持体を駆動させるために大きなトルクを要するため好ましくない。
【０１４５】
静電荷像担持体とトナー担持体との間隙αは、５０〜５００μｍに設定され、ドクターブレードとトナー担持体との間隙は、５０〜４００μｍに設定されることが好ましい。
【０１４６】
トナー担持体上のトナー層の層厚は、静電荷像担持体とトナー担持体との間隙αよりも薄いことが最も好ましいが、場合によりトナー層を構成する多数のトナーの穂のうち、一部は静電荷像担持体に接する程度にトナー層の層厚を規制してもよい。
【０１４７】
一方、トナー担持体には、バイアス電源２６により静電荷像担持体との間に交番電界を印加することによりトナー担持体から静電荷像担持体へのトナーの移動を容易にし、更に良質の画像を得ることが出来る。交番電界のＶｐｐは１００Ｖ以上、好ましくは２００〜３０００Ｖ、更に好ましくは３００〜２０００Ｖで用いるのが良い。また、ｆは５００〜５０００Ｈｚ、好ましくは１０００〜３０００Ｈｚ、更に好ましくは１５００〜３０００Ｈｚで用いられるこの場合の波形は、矩形波、サイン波、のこぎり波、三角波等の波形が適用できる。また、正、逆の電圧、時間の異なる非対称交流バイアスも利用できる。また直流バイアスを重畳するのも好ましい。
【０１４８】
静電荷像担持体１はａ−Ｓｅ，Ｃｄｓ，ＺｎＯ₂ ，ＯＰＣ，ａ−Ｓｉの様な光導電絶縁物質層を持つ感光ドラムもしくは感光ベルトである。静電荷像担持体１は図示しない駆動装置によて矢印方向に回転される。
【０１４９】
静電荷像担持体１としては、アモルファスシリコン感光層、又は有機系感光層を有する感光体が好ましく用いられる。
【０１５０】
有機感光層としては、感光層が電荷発生物質及び電荷輸送性能を有する物質を同一層に含有する、単一層型でもよく、又は、電荷輸送層を電荷発生層を成分とする機能分離型感光層であっても良い。導電性基体上に電荷発生層、次いで電荷輸送層の順で積層されている構造の積層型感光層は好ましい例の一つである。
【０１５１】
有機感光層の結着樹脂はポリカーボネート樹脂、ポリエステル樹脂、アクリル系樹脂が特に、転写性、クリーニング性が良く、クリーニング不良、感光体へのトナーの融着、外添剤のフィルミングが起こりにくい。
【０１５２】
帯電工程では、コロナ帯電器を用いる静電荷像担持体１とは非接触である方式と、ローラ等を用いる接触型の方式がありいずれのものも用いられる。効率的な均一帯電、シンプル化、低オゾン発生化のために図１に示す如く接触方式のものが好ましく用いられる。
【０１５３】
帯電ローラ２は、中心の芯金２ｂとその外周を形成した導電性弾性層２ａとを基本構成とするものである。帯電ローラ２は、静電荷像担持体１面に押圧力をもって圧接され、静電荷像担持体１の回転に伴い従動回転する。
【０１５４】
帯電ローラを用いた時の好ましいプロセス条件としては、ローラの当接圧が５〜５００ｇ／ｃｍで、直流電圧に交流電圧を重畳したものを用いた時には、交流電圧は０．５〜５ｋＶｐｐ、交流周波数は５０Ｈｚ〜５ｋＨｚ、直流電圧は±０．２〜±１．５ｋＶであり、直流電圧のみを用いた時には、直流電圧は±０．２〜±５ｋＶである。
【０１５５】
この他の帯電手段としては、帯電ブレードを用いる方法や、導電性ブラシを用いる方法がある。これらの接触帯電手段は、高電圧が不必要になたり、オゾンの発生が低減するといった効果がある。
【０１５６】
接触帯電手段としての帯電ローラ及び帯電ブレードの材質としては、導電性ゴムが好ましく、その表面に離型性被膜をもうけても良い。離型性被膜としては、ナイロン系樹脂、ＰＶＤＦ（ポリフッ化ビニリデン）、ＰＶＤＣ（ポリ塩化ビニリデン）などが適用可能である。
【０１５７】
静電荷像担持体上のトナー像は、電圧（例えば、±０．１〜±５ｋＶ）が印加されている中間転写体５に転写される。静電荷像担持体表面は、クリーニングブレード８を有するクリーニング手段９でクリーニングされる。
【０１５８】
中間転写体５は、パイプ状の導電性芯金５ｂと、その外周面に形成した中抵抗の弾性体層５ａからなる。芯金５ｂは、プラスチックのパイプに導電性メッキをほどこしたものでも良い。
【０１５９】
中抵抗の弾性体層５ａは、シリコーンゴム、テフロンゴム、クロロプレンゴム、ウレタンゴム、ＥＰＤＭ（エチレンプロピレンジエンの３元共重合体）などの弾性材料に、カーボンブラック、酸化亜鉛、酸化スズ、炭化ケイ素の如き導電性付与材を配合分散して電気抵抗値（体積抵抗率）を１０⁵ 〜１０¹¹Ω・ｃｍの中抵抗に調整した、ソリッドあるいは発泡肉質の層である。
【０１６０】
中間転写体５は静電荷像担持体１に対して並行に軸受けさせて静電荷像担持体１の下面部に接触させて配設してあり、静電荷像担持体１と同じ周速度で矢印の反時計方向に回転する。
【０１６１】
静電荷像担持体１の面に形成担持された第１色のトナー像が、静電荷像担持体１と中間転写体５とが接する転写ニップ部を通過する過程で中間転写体５に対する印加転写バイアスで転写ニップ域に形成された電界によって、中間転写体５の外面に対して順次に中間転写されていく。
【０１６２】
必要により、着脱自在なクリーニング手段１０により、転写材へのトナー像の転写後に、中間転写体５の表面がクリーニングされる。中間転写体上にトナー像がある場合、トナー像を乱さないようにクリーニング手段１０は、中間転写体表面から離される。
【０１６３】
中間転写体５に対して並行に軸受けさせて中間転写体５の下面部に接触させて転写手段が配設され、転写手段７は例えば転写ローラ又は転写ベルトであり、中間転写体５と同じ周速度で矢印の時計方向に回転する。転写手段７は直接中間転写体５と接触するように配設されていても良く、またベルト等が中間転写体５と転写手段７との間に接触するように配置されても良い。
【０１６４】
転写ローラの場合、中心の芯金７ｂとその外周を形成した導電性弾性層７ａとを基本構成とするものである。
【０１６５】
中間転写体及び転写ローラとしては、一般的な材料を用いることが可能である。中間転写体の弾性層の体積固有抵抗値よりも小さく設定することで転写ローラへの印加電圧が軽減でき、転写材上に良好なトナー像を形成できると共に転写材の中間転写体への巻き付きを防止することができる。特に中間転写体の弾性層の体積固有抵抗値が転写ローラの弾性層の体積固有抵抗値より１０倍以上であることが特に好ましい。
【０１６６】
例えば、転写ローラ７の導電性弾性層７ｂはカーボン等の導電材を分散させたポリウレタン、エチレン−プロピレン−ジエン系三元共重合体（ＥＰＤＭ）等の体積抵抗１０⁶ 〜１０¹⁰Ω・ｃｍの弾性体でつくられている。芯金７ａには定電圧電源によりバイアスが印加されている。バイアス条件としては、±０．２〜±１０ｋＶが好ましい。
【０１６７】
本発明のトナーは、転写工程での転写効率が高く、転写残トナーが少ない上に、クリーニング性に優れているので、静電荷像担持体上にフィルミングを生じにくい。さらに、多数枚耐久試験を行っても従来のトナーよりも、本発明のトナーは外添剤のトナー粒子表面への埋没が少ないため、良好な画質を長期にわたって維持し得る。特に静電荷像担持体や中間転写体上の転写残トナーをクリーニングブレードの如きクリーニング手段で除去し、回収された該転写残トナーを再度利用するいわゆるリュース機構を有する画像形成装置に好ましく用いられる。
【０１６８】
次いで転写材６上のトナー画像は加熱加圧定着手段によって定着される。加熱加圧定着手段としては、ハロゲンヒーター等の発熱体を内蔵した加熱ローラーとこれと押圧力をもって圧接された弾性体の加圧ローラーを基本構成とする熱ロール方式や、フィルムを介してヒーターにより加熱定着する方式（図４，５）が挙げられるが、本発明のトナーは定着性と耐オフセット性に優れるので上記の如き加熱加圧定着手段と良好なマッチングを示す。
【０１６９】
以下、具体的実施例によって本発明を説明するが、本発明はなんらこれらに限定されるものではない。
【０１７０】
実施例１
スチレン１３２重量部、アクリル酸ｎ−ブチル６８重量部、ジビニルベンゼン（純度５５％）０．９１重量部、下記直鎖状不飽和ポリエステル４．０重量部、パラフィンワックス（吸熱メインピーク７５℃、数平均分子量８３０）２０重量部、カーボンブラック（ＢＥＴ比表面積＝６０ｍ² ／ｇ、吸油量＝１１５ｍｌ／ｇ）１５重量部、負荷電性制御剤（ジ−ｔｅｒｔ−ブチルサリチル酸の鉄錯体）４．０重量部をアトライター（三井三池工機社製）を用いて充分に混合、分散した。
【０１７１】
直鎖状不飽和ポリエステル：
（ａ）下記フマル酸と下記ビスフェノールＡ誘導体との重縮合物。
【０１７２】
【外９】

（ｂ）重量平均分子量：１万
（ｃ）酸価：１０（ｍｇＫＯＨ／ｇ）
【０１７３】
さらに、２，２’−アゾビス（２，４−ジメチルバレロニトリル）１０重量部を加えてよく撹拌し、重合性単量体組成物を調製した。
【０１７４】
一方、高速撹拌装置ＴＫ式ホモミキサー（特殊機化工業社製）を備えた四つ口容器中にイオン交換水５００重量部と０．１ＭのＮａ₃ ＰＯ₄ 水溶液６５０重量部を投入し、７０℃に加温した。ここに、１．０ＭのＣａＣｌ₂ の水溶液１００重量部を添加し、回転数１００００ｒｐｍで撹拌して微細な難水溶性分散安定剤Ｃａ₃ （ＰＯ₄ ）₂ を含む水系分媒体を調製した。
【０１７５】
重合性単量体組成物を水系分媒体に投入して窒素気流下７０℃に保持しつつ１００００ｒｐｍで７分間撹拌を続けて、造粒を行なった。その後、撹拌をパドル型撹拌翼に切り替え、７０℃で５時間、８０℃で５時間重合させた。
【０１７６】
重合反応終了後、容器中の内容物を室温まで冷却し、これに塩酸を加えて難水溶性分散安定剤を溶解し、濾過、水洗、乾燥を経てトナー粒子（Ａ）を得た。このトナー粒子（Ａ）は、図２（ａ）のように、ワックスはバインダー樹脂と相溶しない状態で実質的に球状を呈し、分散していた。また、トナー粒子（Ａ）の表面にエステル成分が偏在していた。得られたトナー粒子（Ａ）は、ジビニルベンゼンで架橋されたスチレン−アクリル酸ｎ−ブチル共重合体及び不飽和ポリエステルユニットを有する結着樹脂１００重量部に対してパラインワックス約１０重量部、カーボンブラック約７．５重量部、及び負荷電性制御剤約２重量部を含有していた。不飽和ポリエステルは、スチレン及びアクリル酸ｎ−ブチルと反応し、ハイブリッド成分を形成していた。トナー粒子の物性を表１〜３に示す。
【０１７７】
前記トナー粒子（Ａ）１００重量部に疎水性シリカ微粉体（ＢＥＴ；比表面積２００ｍ² ／ｇ）２．０重量部を外添し、本発明のトナー（Ａ）とした後、該トナー（Ａ）６．０重量部とシリコーン樹脂コート磁性フェライトキャリア（平均粒径；５０μｍ）９４重量部とを混合して磁気ブラシ現像用二成分系現像剤（Ａ）を調製した。
【０１７８】
実施例２
下記飽和ポリエステル４重量部を実施例１の重合性単量体組成物にさらに加えることを除いて、実施例１と同様にしてトナー粒子（Ｂ）を生成した。
【０１７９】
飽和ポリエステル：
（ａ）下記テレフタル酸と下記ビスフェノールＡ誘導体との重縮合物。
【０１８０】
【外１０】

（ｂ）重量平均分子量：１．１万
（ｃ）酸価：１２（ｍｇＫＯＨ／ｇ）
【０１８１】
さらに、実施例１と同様にしてトナー（Ｂ）及び現像剤（Ｂ）を調製した。
【０１８２】
実施例３
飽和ポリエステルの添加量を１０重量部とし、ジビニルベンゼン（純度５５％）の添加量を０．３０重量部とした以外は、実施例２と同様にしてトナー粒子（Ｃ）、トナー（Ｃ）、現像剤（Ｃ）を得た。
【０１８３】
実施例４
前記不飽和ポリエステル及び飽和ポリエステルの添加量をそれぞれ５重量部、１５重量部とした以外は、実施例３と同様にしてトナー粒子（Ｄ）、トナー（Ｄ）、現像剤（Ｄ）を得た。
【０１８４】
実施例５
前記不飽和ポリエステル及び飽和ポリエステルの添加量をそれぞれ６重量部、２０重量部とした以外は、実施例３と同様にしてトナー粒子（Ｅ）、トナー（Ｅ）、現像剤（Ｅ）を得た。
【０１８５】
実施例６
ジビニルベンゼン（純度５５％）の添加量を１．８重量部とし、重合反応を６０℃で１０時間行った以外は、実施例１と同様にしてトナー粒子（Ｆ）、トナー（Ｆ）、現像剤（Ｆ）を得た。
【０１８６】
比較例１
不飽和ポリエステルを使用せずに実施例２で使用した飽和ポリエステル２０重量部を使用した以外は、実施例１と同様にして比較トナー粒子（Ｇ）、比較トナー（Ｇ）、比較現像剤（Ｇ）を得た。
【０１８７】
比較例２
ジビニルベンゼン（純度５５％）の添加量を５．０重量部、２，２’−アゾビス（２，４−ジメチルバレロニトリル）の添加量を２重量部とし、重合反応を５０℃で５時間、６０℃で５時間行った以外は、実施例１と同様にして比較トナー粒子（Ｈ）、比較トナー（Ｈ）、比較現像剤（Ｈ）を得た。
【０１８８】
比較例３
・スチレン−アクリル酸ブチル共重合体 １００重量部
（ピーク分子量２．０万、ＭＷ＝３．２万、Ｍｗ／Ｍｎ＝１．８、Ｔｇ＝５９℃）
・実施例１で用いた不飽和ポリエステル ２重量部
・実施例１で用いたカーボンブラック ７．５重量部
・実施例１で用いた負荷電性制御剤 ２重量部
・実施例１で用いたパラフィンワックス １０重量部
【０１８９】
上記混合物を二軸エクストルーダーで溶融混練し、冷却した混練物をハンマーミルで粗粉砕し、粗粉砕物をジェットミルで微粉砕し、分級して比較トナー粒子（Ｉ）を得た。比較トナー粒子（Ｉ）を用い、実施例１と同様にして比較トナー（Ｉ）、比較現像剤（Ｉ）を得た。
【０１９０】
比較トナー粒子（Ｉ）中のワックス成分は図２（ｂ）のように微分散状態であり、トナー粒子表面にもワックスが確認された。
【０１９１】
トナー粒子（Ａ）−（Ｆ）、比較トナー粒子（Ｇ）〜（Ｉ）について、物性粒度分布、形状係数の測定結果及びＴＥＭ観察結果を表１〜３に示す。
【０１９２】
【表１】

【０１９３】
【表２】

【０１９４】
【表３】

【０１９５】
実施例７〜１２及び比較例４〜６
実施例１〜６及び比較例１〜３で調製した各現像を図３に示す、ブラック現像器に入れ、単色モードで画出し試験をおこなった。
【０１９６】
用いた画像形成装置について図３を参照しながら説明する。
【０１９７】
感光体ドラム１は、基材１ａ上に有機光半導体を有する観光層１ｂを有し、矢印方向に回転し、対抗し接触回転する帯電ローラー２（導電性弾性層２ａ、芯金２ｂ）により感光体ドラム１上に約−６００Ｖの表面電位に帯電させた。露光３は、ポリゴンミラーにより感光体上にデジタル画像情報に応じてオン−オフさせることで露光部電位が−１００Ｖ、暗部電位が−６００Ｖのデジタルな静電荷像を形成した。現像器４−４を用いて、感光体１上に反転現像方法により静電荷像を現像し、ブラックトナー像を得た。該トナー像は、中間転写体５（弾性層５ａ、支持体として芯金５ｂ）上に転写され中間転写体５上にトナーが形成される。感光体１上の転写残トナーはクリーナー部材８により、残トナー容器９中に回収した。
【０１９８】
中間転写体５は、パイプ状の芯金５ｂ上にカーボンブラックの導電付与部材をニトリル−ブタジエンラバー（ＮＢＲ）中に十分分散させた弾性層５ｂをコーティングした。該コート層５ｂの硬度は、「ＪＩＳ Ｋ−６３０１」に準拠し３０度で且つ体積固有抵抗値は、１０⁹ Ω・ｃｍであった。感光体１から中間転写体５への転写に必要な転写電流は約５μＡであり、これは電源より＋５００Ｖを芯金５ｂ上に付与することで得られた。
【０１９９】
転写ローラー７の外径２０ｍｍで直径１０ｍｍの芯金７ｂ上にカーボンの導電性付与部材をエチレン−プロピレン−ジエン系三元共重合体（ＥＰＤＭ）の発泡体中に十分分散させたものをコーティングすることにより生成した弾性層７ａを有し、弾性層７ａの体積固有抵抗値は、１０⁶ Ω・ｃｍで、「ＪＩＳ Ｋ−６３０１」の基準の硬度は３５度の値を示すものを用いた。転写ローラーには電圧を印加して１５μＡの転写電流を流した。
【０２００】
加熱加圧定着装置Ｈにはオイル塗布機能のない熱ロール方式の定着装置を用いた。この時上部ローラー、下部ローラー共にフッ素系樹脂の表面層を有するものを使用し、ローラーの直径は６０ｍｍであった。定着温度は１５０℃にし、ニップ幅を７ｍｍに設定した。
【０２０１】
以上の設定条件で、常温常湿（２５℃，６０％ＲＨ）、高温高湿（３０℃，８０％ＲＨ）環境下、８枚（Ａ４サイズ）／分のプリントアウト速度で現像剤（Ａ）〜（Ｉ）の各々において、ブラックトナーを逐次補給しながら単色での連続モード（すなわち、現像器を休止させることなくトナーの消費を促進させるモード）でプリントアウト試験を行い、得られたプリントアウト画像を後述の項目について評価した。
【０２０２】
また、同時に用いた画像形成装置と上記現像剤のマッチングについても評価した。
【０２０３】
クリーニングにより回収された残トナーは、リュース機構により現像器に搬送し、再使用した。
【０２０４】
次に定着器をとりはずし、外部駆動装置をとりつけ１５０ｍｍ／秒で定着ローラーを回転させ、温度制御装置をとりつけて、１００〜２３０℃の範囲で定着ローラーの温度を変えられる様に改造した。
【０２０５】
定着テストは、上部ローラー（加熱ローラー）が所定の温度に達した後に更に１０分間その温度を保持し、下部ローラー（加圧ローラー）が充分に加熱されて、温度が一定になったのを確認してから行った。
【０２０６】
以上の評価結果を表４及び５に示す。
【０２０７】
【表４】

【０２０８】
【表５】

【０２０９】
〔プリントアウト画像評価〕
〈１〉画像濃度
通常の複写機用普通紙（７５ｇ／ｍ² ）に所定の枚数のプリントアウトを終了した時の画像濃度維持により評価した。尚、画像濃度は「マクベス反射濃度計」（マクベス社製）を用いて、原稿濃度が０．００の白地部分のプリントアウト画像に対する相対濃度を測定した。
Ａ：非常に良好（１．４０以上）
Ｂ：良好（１．３５以上乃至１．４０未満）
Ｃ：普通（１．００以上乃至１．３５未満）
Ｄ：悪い（１．００未満）
【０２１０】
〈２〉画像カブリ
「リフレクトメータ」（東京電色社製）により測定したプリントアウト画像の白地部分の白色度と転写紙の白色度の差から、カブリ濃度（％）を算出し、画像カブリを評価した。
Ａ：非常に良好（１．５％未満）
Ｂ：良好（１．５％以上乃至２．５％未満）
Ｃ：普通（２．５％以上乃至４．０％未満）
Ｄ：悪い（４％以上）
【０２１１】
〈３〉定着性
定着性は、５０ｇ／ｃｍ² の荷重をかけ、柔和な薄紙により定着画像を摺擦し、摺擦前後での画像濃度の低下率（％）で評価した。
Ａ：非常に良好（５％未満）
Ｂ：良好（５％以上乃至１０％未満）
Ｃ：普通（１０％以上乃至２０％未満）
Ｄ：悪い（２０％以上）
【０２１２】
〈４〉耐オフセット性
耐オフセット性は、画像面積率約５％のサンプル画像をプリントアウトし、３０００枚後の画像上の汚れの程度により評価した。
Ａ：非常に良好（未発生）
Ｂ：良好（ほとんど発生せず）
Ｃ：普通
Ｄ：悪い
【０２１３】
〈５〉最低定着温度
５０ｇ／ｃｍ² の荷重をかけたレンズクリーニング紙〔ｌｅｎｓ ｃｌｅａｎｉｎｇ ｐａｐｅｒ（“Ｄｕｓｐｅｒ”（ｔｒａｄｅ ｎａｍｅ），ｍｆｄ．ｂｙ ＯＺＵ ｐａｐｅｒ Ｃｏ．Ｌｔｄ．〕により定着画像を１０回摺擦し、摺擦前後での画像濃度の低下率が２０％以下となる最低の定着温度を最低定着温度とする。
【０２１４】
〈６〉耐高温オフセット温度
高温オフセットの発生の有無を目視で判断し、高温オフセットが発生しない最高の定着温度を耐高温オフセット温度とする。
【０２１５】
〔画像形成装置マッチング評価〕
〈１〉現像スリーブとのマッチング
プリントアウト試験終了後、現像スリーブ表面への残留トナーの固着の様子とプリントアウト画像への影響を目視で評価した。
Ａ：非常に良好（未発生）
Ｂ：良好（ほとんど発生せず）
Ｃ：普通（固着があるが、画像への影響が少ない）
Ｄ：悪い（固着が多く、画像ムラを生じる）
【０２１６】
〈２〉感光ドラムとのマッチング
プリントアウト試験終了後、感光体ドラム表面の傷や残留トナーの固着の発生状況とプリントアウト画像への影響を目視で評価した。
Ａ：非常に良好（未発生）
Ｂ：良好（わずかに傷の発生が見られるが、画像への影響は少ない）
Ｃ：普通（固着や傷があるが、画像への影響が少ない）
Ｄ：悪い（固着が多く、縦スジ状の画像欠陥を生じる）
【０２１７】
〈３〉中間転写体とのマッチング
プリントアウト試験終了後、中間転写体表面の傷や残留トナーの固着状況を目視で評価した。
Ａ：非常に良好（未発生）
Ｂ：良好（表面に残留トナーの存在が認められるものの画像への影響はない）
Ｃ：普通（固着や傷があるが、画像への影響が少ない）
Ｄ：悪い（固着が多く、画像欠陥を生じる）
【０２１８】
〈４〉定着装置とのマッチング
プリントアウト試験終了後、定着フィルム表面の傷や残留トナーの固着状況を目視で評価した。
Ａ：非常に良好（未発生）
Ｂ：良好（わずかに固着が見られるものの、画像への影響はない）
Ｃ：普通（固着や傷があるが、画像への影響が少ない）
Ｄ：悪い（固着が多く、画像欠陥を生じる）
実施例１３及び比較例７
【０２１９】
図３に示す画像形成装置の現像装置を図５に示すものに交換し、トナー担持体面の移動速度が静電潜像担持体面の移動速度に対し、３．０倍となるように設定し、トナー（Ａ）と比較用トナー（Ｇ）の各々を逐次補給しながら単色での間歇モード（すなわち、１枚プリントアウトする毎に１０秒間現像器を休止させ、再起動時の現像装置の予備動作でトナーの劣化を促進させるモード）により前記実施例と同様に評価を行った。
【０２２０】
ここで用いたトナー担持体の表面粗度Ｒａは１．５で、トナー規制ブレードは、リン青銅ベース板にウレタンゴムを接着し、トナー担持体との当接面をナイロンによりコートしたものを用いた。また、加熱定着装置Ｈには図６及び図７に示した定着装置を用い、加熱体３１の検温素子３１ｄの表面温度は１３０℃、加熱体２１−シリコンゴムの発泡体を下層に有するスポンジ加圧ローラー３３間の総圧は８ｋｇ、加圧ローラーとフィルムのニップは６ｍｍとし、定着フィルム３２には、転写材との接触面にＰＴＥＦ（高分子量タイプ）に導電性物質を分散させた低抵抗の離型層を有する厚さ６０μｍの耐熱性ポリイミドフィルムを使用した。以上の評価結果を表６に示す。
【０２２１】
【表６】

【０２２２】
実施例１４及び比較例８
市販のレーザービームプリンターＬＢＰ−ＥＸ（キヤノン社製）にリュース機構を取り付け改造して用いた。具体的には、図８において、感光体ドラム６０上の未転写トナーを該感光体ドラムに当接しているクリーナー６１の弾性ブレード６２によりかき落とした後、クリーナーローラーによってクリーナー内部へ送り、更にクリーナースクリュー６３を経て、搬送スクリューを設けた供給用パイプ６４によってホッパー６５を介して現像器２６に戻し、再度、回収トナーを利用するシステムを取り付け、一次帯電ローラー６７としてナイロン樹脂で被覆された導電性カーボンを分散したゴムローラー（直径１２ｍｍ，当接圧５０ｇ／ｃｍ）を使用し、静電潜像担持体にレーザー露光（６００ｄｐｉ）により暗部電位Ｖ_D ＝−７００Ｖ、明部電位Ｖ_L ＝−２００Ｖを形成した。トナー担持体として表面にカーボンブラックを分散した樹脂をコートした表面粗度Ｒａが１．１を呈する現像スリーブ６８を感光体ドラム面の移動速度に対して１．１倍となる様に設定し、次いで、感光体ドラムと該現像スリーブとの間隙（Ｓ−Ｄ間）を２７０μｍとし、トナー規制部材としてウレタンゴム製ブレードを当接させて用いた。現像バイアスとして直流バイアス成分に交流バイアス成分を重畳して用いた。また加熱定着装置の設定温度は１５０℃でした。
【０２２３】
以上の設定条件で、常温常湿（２５℃，６０％ＲＨ）、高温高湿（３０℃，８０％ＲＨ）環境下、１２枚（Ａ４サイズ）／分のプリントアウト速度で、トナー（Ａ）と比較用トナー（Ｇ）の各々を逐次補給しながら間歇モード（すなわち、１枚プリントアウトする毎に１０秒間現像器を休止させ、再軌道時の予備動作でトナーの劣化を促進させるモード）でプリントアウト試験を行い、得られたプリントアウト画像を後述の項目について評価した。
【０２２４】
また、同時に用いた画像形成装置と上記トナーとのマッチングについても評価した。
【０２２５】
以上の評価結果を表７に示す。
【０２２６】
【表７】

【０２２７】
実施例１５
図８のトナーリユース機構を取り外しプリントアウト速度を１６枚（Ａ４サイズ）／分とした以外は、実施例１４と同様にし、前記トナー（Ａ）を逐次補給しながら連続モード（すなわち、現像器を休止させることなくトナーの消費を促進させるモード）でプリントアウト試験を行った。
【０２２８】
得られたプリントアウト画像を後述の項目について評価すると共に、用いた画像形成装置とのマッチングについても評価した。その結果、いずれの項目についても良好であった。
【０２２９】
実施例１６
実施例３において、カーボンブラックのかわりに、イエロー着色剤（Ｃ．Ｉ．ピグメントイエロー１３）６重量部、マゼンタ着色剤（Ｃ．Ｉ．ピグメントレッド５７：１）６重量部、シアン着色剤（Ｃ．Ｉ．ピグメントブルー１５：３）６重量部を使用してそれぞれイエロートナー粒子、マゼンタトナー粒子及びシアントナー粒子をそれぞれ調製した。
【０２３０】
各トナー粒子の物性を表８〜１０に示す。
【０２３１】
実施例１と同様にしてイエロートナー、マゼンタトナー、シアントナー、イエロー現像剤、マゼンタ現像剤及びシアン現像剤を調製し、それぞれ現像器４−１、４−２及び４−３に入れ、実施例１の現像剤〔トナー（Ａ）〕が入っている現像器４−４と供に使用してフルカラーモードで画出し試験をおこなった。オイルレス定着でも、オフセットを生じることなく鮮明なフルカラー画像が得られ、充分な混合性を有していることが判明した。
【０２３２】
【表８】

【０２３３】
【表９】

【０２３４】
【表１０】

【０２３５】
【発明の効果】
以上説明した様に、本発明によれば、極めて良好な低温定着性と耐オフセット性の両立が可能であり、また、高品位な画像を長期に渡って形成することができる。さらに、画像形成装置とのマッチングも好適なものとなる。
【図面の簡単な説明】
【図１】実施例１で生成したトナー粒子（Ａ）のＴＨＦ可溶成分のＧＰＣのクロマトグラムを示す。
【図２】トナー粒子の内部にワックスが分散されているトナー粒子断面の一例を示す模式図である。
【図３】本発明の画像形成方法に好適な画像形成装置の一例の概略的説明図である。
【図４】本発明の実施例に用いた二成分系現像剤用の現像装置の要部の拡大横断面図である。
【図５】本発明の実施例に用いた一成分系現像剤用の現像装置の要部の拡大横断面図である。
【図６】本発明の実施例に用いた加熱加圧定着装置の要部の分解斜視図である。
【図７】本発明の実施例に用いた加熱加圧定着装置の非駆動時のフィルム状態を示した要部の拡大横断面図である。
【図８】未転写トナーをリユースする画像形成装置の一例の概略的説明図である。
【符号の説明】
１ 感光体（静電潜像担持体）
２ 帯電ローラー
３ 露光
４ ４色現像器（４−１、４−２、４−３、４−４）
５ 中間転写体
６ 転写材
７ 転写ローラー
１１ 現像剤担持体
１３ 感光体ドラム
３０ ステー
３１ 加熱体
３１ａ ヒーター基板
３１ｂ 発熱体
３１ｃ 表面保護層
３１ｄ 検温素子
３２ 定着フィルム
３３ 加圧ローラー
３４ コイルばね
３５ フィルム端部規制フランジ
３６ 給電コネクター
３７ 断電部材
３８ 入口ガイド
３９ 出口ガイド（分離ガイド）[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a toner for developing an electrostatic charge image in an image forming method such as electrophotography and electrostatic printing, and an image forming method using the toner. In particular, the present invention relates to an electrostatic charge image developing toner used in a fixing method in which a visible image formed of toner is fixed on a transfer material by heating, and an image forming method using the toner.
[0002]
[Prior art]
Conventionally, electrophotographic methods are known in a number of ways as described in US Pat. No. 2,297,691, Japanese Patent Publication No. 42-23910, Japanese Patent Publication No. 43-24748, and the like. In general, a photoconductive substance is used to form an electrostatic charge image on a photoreceptor by various means, and then the electrostatic charge image is developed using toner, with or without an intermediate transfer member. After a toner image is transferred to a transfer material such as paper, it is fixed by heating, pressing, heating and pressing, or solvent vapor to obtain a copy or print. The untransferred toner remaining without being transferred onto the photoreceptor is cleaned by various methods, and the above-described steps are repeated.
[0003]
An example of a general method for forming a full-color image will be described. The photosensitive drum (electrostatic charge image carrier) of the photosensitive drum is uniformly charged by a primary charger, and image exposure is performed with a laser beam modulated by a magenta image signal of the original to form an electrostatic charge image on the photosensitive drum. Then, the electrostatic charge image is developed by a magenta developing device having magenta toner to form a magenta toner image. Next, the magenta toner image developed on the photosensitive drum by the transfer charger is transferred to the transferred transfer material directly or indirectly using a transfer device.
[0004]
On the other hand, the photosensitive drum after the development of the electrostatic charge image is neutralized by a neutralizing charger, cleaned by a cleaning unit, charged again by a primary charger, and similarly the cyan toner image The cyan toner image is transferred to the transfer material onto which the magenta toner image has been formed and transferred, and the toner images of four colors are transferred to the transfer material in the same manner as yellow and black. The transfer material having the four color toner images is fixed by the action of heat and pressure by a fixing roller, thereby forming a full color image.
[0005]
In recent years, such devices have been used not only in office copy machines for copying original documents, but also in the fields of laser beam printers (LBP) as computer outputs, and personal copy (PC) for individuals. I am starting to break.
[0006]
In addition to such LBP and PC fields, it is also being used for fax.
[0007]
Therefore, miniaturization, weight reduction, high speed, high image quality, and high reliability have been strictly pursued, and machines are configured with simpler elements in various respects. As a result, the performance required for the toner has become higher. In recent years, with the various copying needs, the demand for color copying has increased rapidly, and further higher image quality and higher resolution are desired in order to copy original color images more faithfully. Furthermore, there is an increasing demand for copying original color originals on both sides.
[0008]
From these viewpoints, the toner used in the color image forming method needs to have good meltability and color mixing properties when the toner is heated and pressurized. Therefore, it is preferable to use a toner having a low softening point, a low melt viscosity, and a sharp decrease in melt viscosity at a predetermined temperature (a toner having a high sharp melt property).
[0009]
By using such toner, it is possible to widen the color reproduction range of the copy and obtain a color copy faithful to the original image.
[0010]
However, such a color toner having a high sharp melt property generally has a high affinity with the fixing roller and tends to be offset to the fixing roller during fixing.
[0011]
In particular, in the case of a fixing device in a color image forming apparatus, since a plurality of toner layers of magenta, cyan, yellow, and black are formed on a transfer material, offset tends to occur particularly due to an increase in toner layer thickness.
[0012]
Conventionally, for the purpose of preventing toner from adhering to the surface of the fixing roller, for example, the surface of the roller is coated with a material excellent in releasability from toner such as silicone rubber and fluorine resin, and further, the surface is prevented from being offset and the roller In order to prevent surface fatigue, the roller surface is coated with a thin film of a liquid having high releasability such as silicone oil or fluorine oil. However, this method is extremely effective in preventing toner offset, but has a problem that the fixing device is complicated because an apparatus for supplying the liquid for preventing offset is necessary. This oil application has a detrimental effect of causing peeling between the layers constituting the fixing roller and, consequently, shortening the life of the fixing roller.
[0013]
Therefore, instead of using a silicone oil supply device, a release agent such as low molecular weight polyethylene or low molecular weight polypropylene is added to the toner particles instead of supplying an offset prevention liquid from the toner particles during heating and pressurization. A method has been proposed.
[0014]
Japanese Patent Publication No. 52-3304, Japanese Patent Publication No. 52-3305, and Japanese Patent Publication No. 57-52574 disclose that a toner contains wax as a release agent.
[0015]
Also, JP-A-3-50559, JP-A-2-79860, JP-A-1-109359, JP-A-62-1166, JP-A-61-227354, JP-A-61-94062. JP-A-61-138259, JP-A-60-252361, JP-A-60-252360, and JP-A-60-217366 disclose the inclusion of wax in toner particles. Has been.
[0016]
Waxes are used to improve the offset resistance of toner at low and high temperatures and to improve fixability at low temperatures. On the other hand, blocking resistance tends to be reduced, and toner chargeability tends to be uneven.
[0017]
For the purpose of improving the low-temperature fixability and high-temperature offset resistance of the toner and further improving the blocking resistance, proposals relating to the improvement of the toner binder resin have been made. For example, Japanese Patent Application Laid-Open No. 4-250462 discloses a toner containing a block or graft copolymer of crystalline polyester and a styrene-butadiene copolymer as a binder resin. The gazette discloses a toner containing, as a binder resin, a resin obtained by polymerizing an unsaturated polyester and a vinyl monomer containing 0.01 to 5.0% by weight of a polyfunctional vinyl monomer.
[0018]
However, in the case of the former, since the weight average molecular weight of the styrene-butadiene copolymer before grafting is 730,000 and the molecular weight is very large in the examples, if the polymer after grafting is used as a binder resin, the low-temperature fixability is insufficient. It is.
[0019]
Even in the latter case, the peak molecular weight of the obtained resin exceeds 50,000, and some effects are recognized with respect to the high temperature offset, but further improvement is required with respect to the low temperature fixability.
[0020]
Conventionally, toner has been produced by a so-called pulverization method, but a toner by a suspension polymerization method has also been proposed (Japanese Patent Publication No. 36-10231). In this suspension polymerization method, a monomer composition is prepared by uniformly dissolving or dispersing a polymerizable monomer and a colorant (and, if necessary, a polymerization initiator, a crosslinking agent, a charge control agent, and other additives). Then, the monomer composition is dispersed in an aqueous medium containing a dispersion stabilizer using a suitable stirrer and simultaneously subjected to a polymerization reaction to obtain toner particles having a desired particle size. is there.
[0021]
In order to improve the charging characteristics of the toner by suspension polymerization, Japanese Patent Application Laid-Open No. 56-116043 discloses a vinyl monomer composition containing carbon black and the like, and reactive polyester in 100 parts by weight of monomer. On the other hand, a method for producing toner by adding 10 to 50 parts by weight is disclosed. However, since the unsaturated polyester used has a very large weight average molecular weight of 170,000, and the amount of unsaturated polyester used is large, the total amount of the components insoluble in THF and components having a molecular weight of 1 million or more is 60 wt. %, The low-temperature fixability is insufficient.
[0022]
In the suspension polymerization method, in order to form droplets of the monomer composition in a dispersion medium having a large polarity such as water, the component having a polar group contained in the monomer composition is at the interface with the aqueous phase. A non-polar component that is easily present in a certain surface layer portion can form a so-called core / shell structure existing inside.
[0023]
Japanese Patent Application Laid-Open No. 7-120965 discloses a toner obtained by coating the outer shell of toner particles with a resin mainly composed of amorphous polyester by this suspension polymerization method. In this publication, an amorphous polyester having a tan δ within a range of 1.0 to 20.0 at 80 to 120 ° C. is dissolved in a monomer composition containing styrene and the like and simultaneously polymerized. An outer shell of amorphous polyester is formed. According to this publication, it is possible to obtain a toner having a relatively good fixing property, but the solubility of the tan δ in the monomer of the amorphous polyester having a tan δ of 1.0 to 20.0 is not necessarily good. It is difficult to produce a toner with little variation between particles.
[0024]
By embedding the wax component, which is a release agent, the toner by the polymerization method can achieve conflicting performances such as low-temperature fixability, blocking resistance, and high-temperature offset resistance, and the fixing roller can be separated like oil. It is possible to prevent high temperature offset without applying a mold.
[0025]
As described above, in recent years, there has been a great demand for users to copy originals on both sides or to make double-sided originals on both sides, and for this reason, both images with higher image quality and higher reliability are required. .
[0026]
Among various problems in the conventional color double-sided technology, one of the most important issues is paper curl that occurs after fixing one side. If the paper curl is large, the transportability of the fixed image is poor, and an image with high image quality and high reliability cannot be obtained. On the other hand, the performance required for the toner is, for example, how a high-quality image satisfying image density, color reproducibility, etc. can be obtained with a small amount of toner transferred to the transfer material. is there. For this purpose, it is necessary to improve the coloring power of the toner itself. Further, since an image passing through the fixing device twice is generated on both sides, further improvement in high temperature offset resistance is also required.
[0027]
[Problems to be solved by the invention]
An object of the present invention is to provide a toner for developing an electrostatic charge image in which the above problems are eliminated.
[0028]
The object of the present invention is to improve the fixability and anti-offset property, and to stably provide a high-quality image over a long period of time, and to provide a photoreceptor, a toner carrier, a developer carrier, and an intermediate transfer member. It is an object of the present invention to provide a toner for developing an electrostatic image that can be applied to an electrophotographic process that does not adversely influence, and an image forming method using the toner.
[0029]
[Means for Solving the Problems]
  The present invention is an electrostatic charge image developing toner having toner particles containing at least a binder resin, a colorant and a wax,
(I) Binder resin
  i) a hybrid component in which a vinyl polymer unit of a vinyl polymer component and a polyester unit of a polyester component are bonded to each other;
  ii) In the gel permeation chromatography (GPC) chromatogram of the soluble component of tetrahydrofuran (THF),
  Containing 42 to 95% by weight of component A which is a low molecular weight component having a molecular weight of less than 1 million and a medium molecular weight component,
  2 to 15% by weight of component B, which is a high molecular weight component having a molecular weight of 1 million or more,
  The main peak is in the region of molecular weight 3,000-50,000,
  iii) containing 3 to 55% by weight of component C, which is a THF-insoluble component,
  iv) the total amount of component B and component C is 5 to 58% by weight;
  v) The B component contains 0 to 90% by weight of the polyester component (based on the weight of the B component), and the C component contains 0 to 90% by weight of the polyester component (based on the weight of the C component). And the total amount of the B component and the C component polyester component is 0.02 to 90% by weight (based on the total amount of the B component and the C component),
(II) The present invention relates to an electrostatic charge image developing toner, wherein the toner particle shape factor SF-1 is 100 to 160, and the toner particle shape factor SF-2 is 100 to 140.
[0030]
  Furthermore, the present invention provides a charging step of applying a voltage to the charging member from the outside to charge the electrostatic image carrier, a step of forming an electrostatic image on the charged electrostatic image carrier, and an electrostatic image. Developing with a toner on the toner carrier to form a toner image on the electrostatic image carrier, a transfer step for transferring the toner image on the electrostatic image carrier to a transfer material, and a transfer material A fixing step of fixing the toner image by heating and pressing, and an image forming method,
  The present invention relates to an image forming method, wherein the toner is the above toner.
[0031]
  The present invention further includes a charging step in which a voltage is applied to the charging member from the outside to charge the electrostatic image carrier, and a first electrostatic image is formed on the charged electrostatic image carrier. A developing step of developing the first electrostatic image with the first toner to form the first toner image on the electrostatic image carrier, and the first toner image on the electrostatic image carrier with the intermediate transfer member A first transfer step of transferring to
  A charging step of applying a voltage to the charging member from the outside to charge the electrostatic charge image carrier, a step of forming a second electrostatic charge image on the charged electrostatic charge image carrier, and a second electrostatic charge image Developing with the second toner to form a second toner image on the electrostatic image carrier, and a first toner image transferred to the intermediate transfer member with the second toner image on the electrostatic image carrier A transfer process;
  An image forming method comprising: a second transfer step of transferring a first toner image and a second toner image on an intermediate transfer member onto a transfer material; and a fixing step of heating and fixing the toner image on the transfer material. Yes,
  The present invention relates to an image forming method, wherein each toner is the above toner.
[0032]
DETAILED DESCRIPTION OF THE INVENTION
In the present invention, the toner particles contain at least a binder resin, a colorant and a wax, (I) the binder resin includes a vinyl polymer component and a polyester component; (II) the binder resin is 40 to 99% by weight of component A, 0 to 20% by weight of component B and 0 to 60% by weight of component C. The total amount of component B and component C is 1 to 60% by weight. In the gel permeation chromatography (GPC) chromatogram of the soluble component of tetrahydrofuran (THF) of the adhesion resin, a low molecular weight component having a molecular weight of less than 1 million and a medium molecular weight component are shown. Component B is soluble in THF of the binder resin In the chromatogram of the component GPC, a high molecular weight component having a molecular weight of 1 million or more is shown, and component C is an insoluble component of the binder resin THF; (III) THF soluble component of the binder resin In the PC chromatogram, the main peak is in the region of molecular weight 3,000 to 50,000; (IV) the toner particle shape factor SF-1 is 100 to 160, and the toner particle shape factor SF-2 is 100 to 160. 140.
[0033]
The vinyl polymer constituting the vinyl polymer component may be a vinyl homopolymer such as a styrene homopolymer, or a vinyl copolymer such as a styrene-acrylic copolymer.
[0034]
Examples of vinyl monomers for producing vinyl polymers include styrene; styrene monomers such as o (m-, p-,)-methylstyrene, m (p-)-ethylstyrene; (meta) Methyl acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, octyl (meth) acrylate, dodecyl (meth) acrylate, stearyl (meth) acrylate, (meth) acrylic (Meth) acrylate monomers such as behenyl acid, 2-ethylhexyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate; butadiene, isoprene, cyclohexene, (meth) Monomers such as acrylonitrile and acrylamide are preferably used. These monomers are used alone or as appropriate so that the theoretical glass transition temperature (Tg) described in the publication Polymer Handbook 2nd edition III-P139-192 (manufactured by John Wiley & Sons) is 40-75 ° C. Used as a mixture. When the theoretical glass transition temperature is less than 40 ° C., problems are likely to occur from the viewpoint of storage stability and durability stability of the toner, while when it exceeds 75 ° C., the fixing temperature of the toner increases. In particular, in the case of a color toner for forming a full-color image, the color mixing property at the time of fixing each color toner is lowered, the color reproducibility is poor, and the transparency of the OHP image is further lowered.
[0035]
The molecular weight of the binder resin is measured by gel permeation chromatography (GPC). As a specific GPC measurement method, a sample solution is prepared by filtering a binder resin or a solution containing a binder resin-containing toner in tetrahydrofuran (THF) through a solvent-resistant membrane filter having a pore diameter of 0.2 μm. The measurement is performed using, for example, 150C manufactured by Waters. At this time, the sample solution is adjusted to be 0.05 to 0.6 wt% based on the binder resin, and the injection amount of the sample solution is 50 to 200 μl. For example, A-801, 802, 803, 804, 805, 806, 807 manufactured by Showa Denko can be connected to measure the molecular weight distribution using a standard polystyrene resin calibration curve.
[0036]
GPC measurement conditions for binder resin
Apparatus: GPC-150C (manufactured by Waters)
Column: 7 columns of KF801-7 (manufactured by Shodex)
Temperature: 40 ° C
Solvent: THF
Flow rate: 1.0 ml / min
Sample: 0.1 ml of a sample having a concentration of 0.05 to 0.6% by weight is injected.
[0037]
In measuring the molecular weight of a sample, the molecular weight distribution of the sample is calculated from the relationship between the logarithmic value of a calibration curve prepared from several types of monodisperse polystyrene standard samples and the number of counts. Examples of standard polystyrene samples for preparing a calibration curve include Pressure Chemical Co. Made by Toyo Soda Industry Co., Ltd.² 2.1 × 10^Three 4 × 10^Three 1.75 × 10^Four 5.1 × 10^Four 1.1 × 10^Five 3.9 × 10^Five 8.6 × 10^Five 2 × 10⁶ 4.48 × 10⁶ It is applicable to use at least about 10 standard polystyrene samples. An RI (refractive index) detector is used as the detector. An example of a GPC chromatogram is shown in FIG.
[0038]
The binder resin in the present invention has 0 to 20% by weight of the B component having a molecular weight of 1,000,000 or more in GPC of THF-soluble content based on the total binder resin. Although the high-temperature offset property is good, the low-temperature fixing is lowered. The weight% of component B is calculated as follows.
[0039]
Toner particles or 1 g of toner is precisely weighed and charged into a cylindrical filter paper, and Soxhlet extracted with 200 ml of THF for 20 hours. Thereafter, the cylindrical filter paper is taken out and sufficiently dried under vacuum at 30 to 40 ° C., and the weight of the residue is measured.
[0040]
Since the toner contains components other than the binder resin, such as pigments, charge control agents, release agents, and external additives, considering their content and whether they are soluble or insoluble in THF. The THF-insoluble matter (C component) of the binder resin is calculated.
[0041]
[Outside 3]

[0042]
Next, the molecular weight distribution of the binder resin in the toner is measured by GPC as described above, and the area% of the B component having a molecular weight of 1,000,000 or more is calculated based on the THF soluble content of the binder resin. At this time, it is assumed that the calculated area% is the same as the weight%, and converted to weight% based on the total binder resin (including THF-insoluble matter).
[0043]
When a component soluble in THF other than the binder resin and a component soluble in THF (for example, a wax soluble in THF, etc.) is used, component A or The ratio of the component A and the component B in the binder resin component is determined by subtracting the weight of the component soluble in THF other than the binder resin from the component B.
[0044]
The value calculated as described above is defined as the weight percent of the B component having a molecular weight of 1,000,000 or more based on the total binder resin.
[0045]
In the present invention, the above-described THF-insoluble matter (component C) of the binder resin is 0 to 60% by weight based on the total binder resin. If it is more than this, the low-temperature fixing is lowered. Even if the THF-insoluble content is 0% by weight, the offset resistance and the durability of a large number of sheets are good if the B component is in the range of 1 to 20% by weight.
[0046]
The total amount of the B component and the C component of the binder resin is 1 to 60% by weight, and preferably 5 to 58% by weight. When the total amount of the B component and the C component is less than 1% by weight, the high temperature offset resistance, the blocking resistance, and the developability are deteriorated. .
[0047]
The binder resin component C (resin component insoluble in THF) can be prepared by a method of copolymerizing a monomer such as styrene and a crosslinking agent such as divinylbenzene, or in the presence of an unsaturated polyester. Can be obtained by a method of polymerizing a crosslinking agent.
[0048]
From the viewpoint of blocking resistance and developability, the B component and / or C component preferably contains a polyester component. The content of the polyester component is 0.02 to 90% by weight, preferably 0.2 to 80% by weight, more preferably 1 to 70% by weight, based on the total weight of the B component and the C component. When the content of the polyester component is lower than 0.02% by weight, the blocking resistance and developability deteriorate, and when it exceeds 90% by weight, the development characteristics deteriorate. The polyester component is preferably 0.1 to 20% by weight, more preferably 0.1 to 10% by weight, and most preferably 0.1 to 5% by weight, based on the weight of the binder resin. It is good in terms of development characteristics and environmental stability. The polyester component contained in the B component and the C component can be qualitatively and quantitatively determined as follows, for example.
[0049]
In order to analyze the THF-insoluble matter, toner particles or toner is subjected to Soxhlet extraction with THF as described above, and then the resin component in the dried residue is analyzed by a nuclear magnetic resonance spectrum (¹ H-NMR,¹³Various methods such as spectral analysis such as C-NMR), infrared absorption spectrum (IR), ultraviolet absorption spectrum (UV), mass spectrum (MS), elemental analysis, and other chemical analysis (for example, measurement of acid value and hydroxyl value). It is sufficient to analyze by. It is also possible to apply a method in which a dye that reacts with a hydroxyl group or a carboxyl group in the structure of the polyester component is bonded to the polyester component and a visible spectrum analysis is performed. These analysis means may be used alone or in combination.
[0050]
The qualitative and quantitative determination of the polyester component in the B component may be performed, for example, by analysis using GPC-IR in which IR is directly connected to GPC. For example, the GPC results may be accurately obtained using a preparative HPLC apparatus shown below. The conditions are set so that they are reflected, and the B component is first collected and analyzed by the analysis means as described above.
[0051]
Preparative HPLC system: Recycle preparative HPLC LC-908
(Nippon Analytical Industry)
Preparative column: JAIGEL-1H-6H, JAIGEL-LS205
Select from (Nippon Analytical Industrial Co., Ltd.)
Confirmation of the sample after fractionation follows the GPC measurement method described above.
[0052]
As other analysis means, a method of sufficiently quantifying the polyester component by sufficiently separating the collected B component and then separately extracting it with a single or mixed solvent may be employed.
[0053]
The B component and C component containing 0.02 to 90% by weight of the polyester component can be produced from a reactive polyester.
[0054]
Reactive polyesters include terephthalic acid, isophthalic acid, phthalic acid, adipic acid, maleic acid, succinic acid, sebacic acid, thiodiglycolic acid, diglycolic acid, malonic acid, glutamic acid, pimelic acid, suberic acid, azelaic acid, gypsum Polybasic acids such as oxalic acid, cyclohexanedicarboxylic acid, trimellitic acid; ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, neopentyl Glycol, 1,4-bis (hydroxymethyl) cyclohexane, 1,4-bis (2-hydroxyethyl) benzene, 1,4-cyclohexanedimethanol, polyethylene glycol, polypropylene glycol, bisphenol A, hydrogenated bisphenol Le, ethylene oxide adduct of bisphenol A, propylene oxide adduct of bisphenol A, glycerol, trimethylolpropane, and the like obtained by condensation polymerization of such polyhydric alcohols pentaerythritol. The obtained condensation polymer (reactive polyester) has a reactive group in its main chain or side chain. Examples of the reactive group include carboxylic acid (or a salt thereof), sulfonic acid (or a salt thereof), ethyleneimino acid, an epoxy group, an isocyanate group, a double bond, an acid anhydride, and a halogen atom. Either react these reactive polyesters with each other, or react with a polyfunctional crosslinking agent (for example, polyhydric alcohol, polybasic acid, etc.), or react reactive polyester with a vinyl monomer (for example, copolymerization) B component and C component can be obtained. For example, when producing toner particles directly from a monomer composition by a polymerization method, an unsaturated polyester is used as a reactive polyester, and a vinyl monomer (including a crosslinking agent such as divinylbenzene if necessary) is used. B component and C component can be obtained by copolymerization. In this case, it is easy to form the surface (outer shell) of the toner particles with a B component or a C component containing a polyester component, and toner particles having particularly excellent blocking resistance and offset resistance can be obtained. Is possible.
[0055]
In order to produce the component C, it is preferable to use a polyfunctional vinyl monomer as a crosslinking agent. Examples of the polyfunctional vinyl monomer include aromatic divinyl compounds such as divinylbenzene and divinylnaphthalene; carboxyls having two double bonds such as ethylene glycol diacrylate, ethylene glycol methacrylate, and 1,3-butanediol dimethacrylate. Acid esters; divinyl aniline, divinyl ether, divinyl sulfide, divinyl compounds such as divinyl sulfone; and compounds having three or more vinyl groups. These can be used alone or in combination.
[0056]
If the reactive porester that can be used in the present invention has a too low molecular weight, a polyester that does not participate in the crosslinking reaction may be present on the surface of the toner particles, and the blocking resistance may be lowered. On the other hand, if the toner particles are too high in molecular weight, it is difficult to produce the toner particles because it is difficult to dissolve the reactive polyester in the vinyl monomer when the toner particles are obtained directly by the polymerization method. Accordingly, the weight average molecular weight of the reactive polyester is preferably from 3,000 to 100,000 to obtain a toner having particularly excellent performance. When the reactive polyester is an unsaturated polyester, the weight average molecular weight (Mw) is preferably from 3,000 to 100,000, and particularly when the MW is from 3,000 to 30,000, the reaction with the vinyl monomer. Therefore, the B component and the C component having more preferable electrophotographic characteristics can be generated.
[0057]
The binder resin preferably contains B as a component based on the weight of the binder resin and contains 5 to 58% by weight of the components in terms of improvement in high-temperature offset resistance and blocking resistance. More preferably, the binder resin contains 2 to 15% by weight (more preferably 2 to 10% by weight) of the B component and 3 to 55% by weight (more preferably 5 to 45% by weight) of the C component. Good to do. Further, the total weight of the B component and the C component is 7 to 49% by weight, and the THF soluble content of the binder resin is preferably at least 50% by weight from the viewpoint of low temperature fixing property and color mixing property.
[0058]
When the polyester component is produced from an unsaturated polyester having reactivity with a vinyl monomer, the unsaturated polyester should have the following bisphenol A derivative unit in terms of electrophotographic characteristics and fixability. Is preferable.
[0059]
[Outside 4]

(In the formula, R is an ethylene or propylene group, x and y are each an integer of 1 or more, and the average value of x + y is 2 to 10).
[0060]
Unsaturated polyesters that are reactive with vinyl monomers are dicarboxylic acids having vinyl groups (reactive double bonds) as maleic acid, maleic anhydride, maleic acid esters, fumaric acid or fumaric acid esters. Those obtained by polycondensation with a hydric alcohol component are good. In particular, the divalent alcohol component is preferably a bisphenol A derivative represented by the following formula (A).
[0061]
[Outside 5]

(In the formula, R is an ethylene or propylene group, x and y are each an integer of 1 or more, and the average value of x + y is 2 to 10).
[0062]
The A component, the B component, and the C component are not limited to one type of polymer. For example, two or more reactive polyesters may be used simultaneously, or two or more vinyl polymers may be used. Polyester, epoxy resin, polycarbonate, polyolefin, polyvinyl acetate, polyvinyl chloride, polyalkyl vinyl ether, polyalkyl vinyl ketone, polystyrene, poly (meth) acrylic ester, melamine formaldehyde resin, polyethylene terephthalate with completely different types of reactivity A polymer such as nylon or polyurethane may be added to the binder resin as necessary.
[0063]
In the present invention, the THF-soluble component of the binder resin has a main peak in the molecular weight range of 3,000 to 50,000 in the GPC molecular weight distribution. More preferably, it has a main peak in a molecular weight range of 3,000 to 40,000, and most preferably 10,000 to 30,000 in terms of low-temperature fixability and multi-sheet durability. When the molecular weight is smaller than 3,000, high temperature offset or blocking may occur, and when the molecular weight is larger than 50,000, the low temperature fixing is lowered.
[0064]
The THF-soluble component of the binder resin preferably has a weight average molecular weight of 100,000 or more in order to improve the high temperature offset resistance.
[0065]
The binder resin contains 40 to 99% by weight of component A based on the weight of the binder resin, more preferably 42 to 95% by weight, and most preferably 51 to 93% by weight. Is preferable in terms of fixing properties. In particular, 0 to 20% (more preferably 0.5 to 15%) of a component having a molecular weight of 1,000,000 or more in terms of the area ratio of the chromatogram of GPC based on the weight of THF soluble in the binder resin, and a molecular weight of 50 Having a component of 1,000 to 1,000,000 (more preferably 20 to 40%) and 45 to 85% (more preferably 50 to 79%) of a component having a molecular weight of 50,000 or less. In view of satisfactory satisfactory high temperature offset resistance and low temperature fixability, it is preferable.
[0066]
The component A is a polymer obtained from a vinyl monomer in an amount of 70% by weight or more, more preferably 75% by weight or more, and still more preferably 85% by weight or more. Such other polymers may be contained, but if the content of the polymer obtained from the vinyl monomer is less than 70% by weight, the environmental stability and the low-temperature fixability are unfavorable.
[0067]
The qualitative and quantitative determination of the polymer in the component A may be performed in the same manner as the method for analyzing the polyester component described above.
[0068]
In the present invention, a wax is contained as a release agent.
[0069]
Examples of the wax used in the present invention include paraffin wax and derivatives thereof, microcrystalline wax and derivatives thereof, Fischer-Tropsch wax and derivatives thereof, polyolefin wax and derivatives thereof, carnauba wax and derivatives thereof, and the derivatives include oxides. And block copolymers with vinyl monomers and graft modified products. Other examples include higher fatty acids and their metal salts, higher aliphatic alcohols, higher aliphatic esters, aliphatic amide waxes, ketones, hydrogenated castor oil and derivatives thereof, plant waxes, animal waxes, mineral waxes, and petrolactams. .
[0070]
These waxes preferably have an endothermic main peak in the region of 40 to 150 ° C. when the temperature rises in a DSC endothermic curve measured by a differential scanning calorimeter. By having an endothermic main peak in the above temperature range, the mold releasability is effectively exhibited while greatly contributing to low-temperature fixing. When the maximum endothermic peak is less than 40 ° C., the self-cohesive force of the wax becomes weak. As a result, the high temperature offset resistance decreases and the gloss becomes too high. On the other hand, when the maximum endothermic peak exceeds 150 ° C., the fixing temperature increases and it becomes difficult to appropriately smooth the surface of the fixed image. In particular, when it is used for a color toner, it is not preferable from the viewpoint of color mixing deterioration. Further, when granulation / polymerization is carried out in an aqueous medium and a toner is directly obtained by a polymerization method, if the maximum endothermic peak temperature is high, problems such as precipitation of a wax component mainly during granulation are undesirable.
[0071]
The maximum endothermic peak temperature of the wax component is measured according to “ASTM D 3418-8”. For the measurement, for example, DSC-7 manufactured by PerkinElmer is used. The temperature correction of the device detection unit uses the melting points of indium and zinc, and the correction of heat uses the heat of fusion of indium. An aluminum pan is used as a measurement sample, an empty pan is set as a control, and measurement is performed at a heating rate of 10 ° C./min.
[0072]
More preferably, the wax preferably has an endothermic main peak at a temperature of 45 to 145 ° C. (most preferably 50 to 100 ° C.) in the DSC endothermic curve. In particular, in the case of color toner, the endothermic main peak is in the range of 50 to 100 ° C. from the viewpoint of color mixing and offset resistance.
[0073]
In the present invention, the addition amount of these wax components is not particularly limited, but generally 2 to 30% by weight (more preferably 3 to 25% by weight) with respect to the toner is preferable.
[0074]
An antioxidant may be added to the wax within a range that does not affect the chargeability of the toner.
[0075]
The toner particles used in the toner of the present invention have a surface formed of a binder resin containing a polyester component in a tomographic observation using a transmission electron microscope (TEM). It is preferable that the binder resin and the wax to be present are present, and that the wax is incompatible with the binder resin and has a substantially spherical and / or spindle-shaped structure dispersed in islands as shown in FIG. . By encapsulating the wax in the binder resin and forming the surface with the binder resin containing the polyester component, even if the toner particles contain a large amount of wax, the toner is deteriorated and the image forming apparatus is contaminated. Therefore, a good triboelectric chargeability can be maintained, and a toner image obtained by faithfully developing a digital latent image can be formed over a long period of time. In addition, since a large amount of wax acts efficiently during heating and pressurization, the low temperature fixing property and the offset resistance are satisfied.
[0076]
As a specific method for measuring the tomographic plane of the toner particles, the toner particles are sufficiently dispersed in a room temperature curable epoxy resin and then cured in an atmosphere at a temperature of 40 ° C. for 2 days. The resulting cured product is dyed with ruthenium tetroxide and, if necessary, osmium tetroxide, and then a flaky sample is cut out using a microtome with diamond teeth, and a toner using a transmission electron microscope (TEM) Measure the fault morphology of particles. A structure using a wax as a core and a binder resin as an outer shell uses a ruthenium tetroxide dyeing method in order to provide a contrast between materials by utilizing a slight difference in crystallinity between the wax and the resin. When the toner particles obtained in Examples described later were observed on a tomographic plane with a TEM, the wax was present in a spherical (and / or spindle-shaped) island shape in the binder resin as shown in FIG.
[0077]
The toner particles used in the present invention have a shape factor SF-1 measured by an image analyzer of 100 to 160 (preferably 100 to 140) and a shape factor SF-2 of 100 to 140 (preferably). Is 100-120).
[0078]
In the present invention, SF-1 indicating the shape factor of toner particles is a random sampling of 100 toner images magnified at a magnification of 500 times using, for example, FE-SEM (S-800) manufactured by Hitachi, Ltd. The image information is analyzed by introducing, for example, an image analysis apparatus (Luzex III) manufactured by Nicole via an interface, and a value obtained from the following equation is defined as a shape factor SF-1.
[0079]
[Outside 6]

[Where MXLNG indicates the absolute maximum length of the toner particles and AREA indicates the projected area of the toner particles].
[0080]
Furthermore, the shape factor SF-2 refers to a value obtained by calculation from the following equation.
[0081]
[Outside 7]

[Where PERI indicates the peripheral length of the toner particles and AREA indicates the projected area of the toner particles].
[0082]
The shape factor SF-1 indicates the degree of roundness of the toner particles, and the shape factor SF-2 indicates the degree of unevenness of the toner particles.
[0083]
Conventionally, when the shape factor SF-1 or SF-2 of the toner particles is small, a cleaning failure is likely to occur, or the external additive is easily embedded in the toner particle surface when used for a long time. As a result, the image quality often deteriorates. In the present invention, since the toner particle surface is formed of the B component and / or the C component containing the polyester component, the toner particles have an appropriate strength, so that these problems can be prevented.
[0084]
When the shape factor SF-1 exceeds 160, the shape of the toner particles becomes indeterminate, so that the toner charge distribution becomes broad and the surface of the toner particles is easily ground in the developing device. And image fogging. In addition, when an intermediate transfer member is used in the image forming apparatus, a reduction in the transfer efficiency of the toner image at the time of transfer from the electrostatic charge image carrier to the intermediate transfer member is observed, and further, when transferring from the intermediate transfer member to the transfer material. A decrease in toner image transfer efficiency is also observed.
[0085]
In order to increase the transfer efficiency of the toner image, the shape factor SF-2 of the toner particles is 100 to 140, and more preferably, the value of (SF-2) / (SF-1) is 1.0 or less. Is good. When the shape factor SF-2 of the toner particles exceeds 140 and the value of (SF-2) / (SF-1) exceeds 1.0, the surface of the toner particles is not smooth and the toner particles have a large number of irregularities. Therefore, the transfer efficiency tends to decrease during transfer from the electrostatic charge image bearing member to the intermediate transfer member and during transfer from the intermediate transfer member to the transfer material.
[0086]
Even when the shape factors SF-1 and SF-2 of the toner in which the external additive is externally added to the toner particles are measured, the external additive has a very small particle size or a coarse particle size. Even if it exists, it is very small compared to the number of toner particles, and therefore, it is not substantially different from the shape factors SF-1 and SF-2 of the toner particles.
[0087]
When an intermediate transfer member is used to cope with various transfer materials, the transfer process is performed twice, so that a decrease in transfer efficiency tends to cause a decrease in toner utilization efficiency. In digital full-color copiers and digital full-color printers, color image originals are color-separated beforehand using a B (blue) filter, G (green) filter, and R (red) filter, and then a dot latency of 20 to 70 μm is formed on the photoreceptor. An image is formed and a multicolor image faithful to the original is reproduced by using a primary color mixing action using each color toner of Y (yellow) toner, M (magenta) toner, C (cyan) toner, and B (black) toner. There is a need. At this time, since a large amount of Y toner, M toner, C toner, and B toner is loaded on the photosensitive member or intermediate transfer member in accordance with the color information of the document or CRT, each color toner is transferred extremely high. Sex is required. To achieve this, toner particles whose toner particle shape factors SF-1 and SF-2 satisfy the above conditions are preferred.
[0088]
Furthermore, in order to faithfully develop minute latent image dots for higher image quality, the toner particles have a weight average diameter of 4 to 9 μm (more preferably 4 μm to 8 μm) and a coefficient of variation in the number distribution of 35%. The following is preferable. In toner particles having a weight average diameter of less than 4 μm, there are many toner particles remaining on the photosensitive member or intermediate transfer member due to a decrease in transfer efficiency, and this tends to cause uneven image unevenness due to fogging or transfer failure. . When the weight average diameter of the toner particles exceeds 9 μm, the surface of the photoreceptor and the intermediate transfer material are likely to be fused to each other. This tendency is further enhanced when the coefficient of variation in the number distribution of toner particles exceeds 35%.
[0089]
The particle size distribution of the toner particles can be measured by various methods. For example, the coulter counter method is used.
[0090]
For example, a Coulter Counter TA-II type or Coulter Multisizer (manufactured by Coulter Inc.) is used as a measuring device, and an interface (manufactured by Nikkiki Co., Ltd.) for outputting the number distribution and volume distribution is connected to a personal computer. Prepare approximately 1% NaCl aqueous solution using sodium chloride. For example, ISOTON II (manufactured by Coulter Scientific Japan) can be used. As a measuring method, 0.1 to 5 ml of a surfactant (preferably alkylbenzene sulfonate) is added as a dispersant to 100 to 150 ml of the electrolytic aqueous solution, and 2 to 20 mg of a measurement sample is further added. The electrolyte in which the sample is suspended is subjected to a dispersion process with an ultrasonic disperser for about 1 to 3 minutes, and the measurement device is used to measure the particle size distribution of 2 to 40 μm particles based on the number, for example, using a 100 μm aperture as the aperture. Then, the value according to the present invention is obtained.
[0091]
The coefficient of variation in the number distribution of toner particles is calculated from the following equation.
[0092]
Coefficient of variation = [S / D₁ ] × 100
[In the formula, S represents a standard deviation value in the number distribution of toner particles, and D₁ Represents the number average particle diameter (μm) of the toner particles].
[0093]
Even when the toner in which the external additive is mixed is measured, the weight and number of the external additive having a particle diameter of 2 μm or more are much smaller than the toner particles, and therefore the value is substantially the same as that of the toner particles.
[0094]
Examples of the colorant used in the present invention include the following yellow colorant, magenta colorant, and cyan colorant. As the black colorant, carbon black, magnetic substance, or yellow colorant / magenta colorant / cyan color shown below. What was mixed with the agent and was toned to black is used.
[0095]
As the yellow colorant, compounds typified by condensed azo compounds, isoindolinone compounds, anthraquinone compounds, azo metal complexes, methine compounds, and allylamide compounds are used. Specifically, C.I. I. Pigment Yellow 12, 13, 14, 15, 17, 62, 74, 83, 93, 94, 95, 109, 110, 111, 128, 129, 147, 168, 180, etc. are preferably used.
[0096]
As the magenta colorant, condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinones, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, and perylene compounds are used. Specifically, C.I. I. Pigment Red 2, 3, 5, 6, 7, 23, 48; 2, 48; 3, 48; 4, 57; 1, 81; 1, 144, 146, 166, 169, 177, 184, 185, 202, 206, 220, 221, 254 are particularly preferred.
[0097]
As the cyan colorant, copper phthalocyanine compounds and derivatives thereof, anthraquinone compounds, basic dye lake compounds, and the like can be used. Specifically, C.I. I. Pigment Blue 1, 7, 15, 15: 1, 15: 2, 15: 3, 15: 4, 60, 62, 66 and the like can be suitably used.
[0098]
These colorants can be used alone or in combination and further in the form of a solid solution. The colorant is selected from the viewpoints of hue, saturation, lightness, weather resistance, OHP transparency, and dispersibility in the toner particles. The added amount of the colorant is preferably 1 to 20 parts by weight with respect to 100 parts by weight of the binder resin.
[0099]
When a magnetic material is used as the black colorant, it is preferable to use 40 to 150 parts by weight with respect to 100 parts by weight of the binder resin, unlike other colorants.
[0100]
A charge control agent may be used in the toner of the present invention. As the charge control agent, known ones can be used, and in particular, a charge control agent that has a high charging speed and can stably maintain a constant charge amount is preferable. Further, when a direct polymerization method is used for toner particles, a charge control agent having no polymerization inhibitory property and having no solubilized product in an aqueous dispersion medium is particularly preferable. Specific compounds include, as negative charge control agents, metal compounds of aromatic carboxylic acids such as salicylic acid, alkylsalicylic acid, dialkylsalicylic acid, naphthoic acid and dicarboxylic acid; polymer type having a sulfonic acid or carboxylic acid group in the side chain A compound; a boron compound; a urea compound; a silicon compound; Examples of the positive charge control agent include quaternary ammonium salts; polymer type compounds having the quaternary ammonium salt in the side chain; guanidine compounds; imidazole compounds. The charge control agent is preferably used in an amount of 0.5 to 10 parts by weight with respect to 100 parts by weight of the resin. However, in the present invention, it is not essential to add a charge control agent. When a two-component development method is used, friction charging with a carrier is used, and when a non-magnetic one-component blade coating development method is used, It is not always necessary to include a charge control agent in the toner particles by actively utilizing frictional charging with the blade member or the sleeve member.
[0101]
As a method for producing the toner of the present invention, a resin, a release agent (wax) composed of a low softening point substance, a colorant, a charge control agent, and the like are uniformly dispersed using a pressure kneader, an extruder, or a media dispersing machine. After that, it is made to collide with a target under a mechanical or jet stream and pulverized to a desired toner particle size (adding a toner particle smoothing and spheroidizing step if necessary), followed by a classification step. In addition to a toner manufacturing method by a pulverization method that sharpens the particle size distribution and makes the toner, a spherical toner is obtained by atomizing the molten mixture into the air using a disk or a multi-fluid nozzle described in JP-B-56-13945. And the suspension polymerization method described in JP-B-36-10231, JP-A-59-53856, and JP-A-59-61842. A toner that is soluble in the monomer, or a dispersion polymerization method that directly produces a toner using an aqueous organic solvent that is insoluble in a polymer, or a polymer obtained by direct polymerization in the presence of a water-soluble polar polymerization initiator. The toner can be produced using an emulsion polymerization method typified by a soap-free polymerization method to be generated.
[0102]
In the method for producing toner using the pulverization method, it is difficult to keep SF-1 and SF-2, which are toner shape factors measured by Luzex, within a desired range. In the melt spray method, SF-1 is used. Even if the value can be within the range of 100 to 160, the particle size distribution of the obtained toner particles tends to be wide. On the other hand, in the dispersion polymerization method, the obtained toner shows a very sharp particle size distribution, but the production equipment is used from the viewpoint of the processing of the waste solvent and the flammability of the solvent due to the narrow selection of materials to be used and the use of organic solvents. Complicated and complicated. An emulsion polymerization method typified by soap-free polymerization is effective because the particle size distribution of the toner is relatively uniform, but the used emulsifier and polymerization initiator terminals are present on the surface of the toner particles, and the environmental characteristics are liable to deteriorate.
[0103]
In the present invention, the shape factor SF-1 value of the toner can be controlled to 100 to 160, and the emulsion can be emulsified under normal pressure or under pressure where toner particles having a sharp particle size distribution and a particle size of 4 to 9 μm can be obtained relatively easily. Using a polymerization method or a suspension polymerization method, a pre-obtained polymer is shaped using a medium, a method in which the polymer is directly collided with a pressure impingement plate, and further, the obtained polymer is placed in an aqueous medium. The particles may be frozen by freezing, or the particles having salt breaks or opposite surface charges may be coalesced by considering conditions such as pH, and agglomerated and coalesced. Further, a seed polymerization method may be used in which a monomer is further adsorbed to the obtained polymer particles and then polymerized using a polymerization initiator.
[0104]
When using a direct polymerization method in which particles of a polymerizable monomer composition are polymerized in an aqueous medium as a method for producing toner particles, the particle size distribution control and particle size control of the toner particles are difficult to achieve with a water-soluble inorganic salt or a protective agent. The method of changing the type and amount of the colloidal dispersant and the mechanical equipment conditions (for example, the rotor speed, the number of passes, the stirring conditions such as the shape of the stirring blade and the shape of the container), or the solid content concentration in the aqueous solution By controlling, predetermined toner particles can be obtained.
[0105]
Examples of the polymerization initiator used when producing toner particles by the direct polymerization method include 2,2'-azobis- (2,4-dimethylvaleronitrile), 2,2'-azobisisobutyronitrile, Azo- or azobis-based polymerization initiators such as 1,1'-azobis (cyclohexane-1-carbonitrile), 2,2'-azobis-4-methoxy-2,4-dimethylvaleronitrile, azobisisobutyronitrile; Peroxide-based polymerization initiators such as benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, cumene hydroperoxide, 2,4-dichlorobenzoyl peroxide, lauroyl peroxide are used. The amount of the polymerization initiator used varies depending on the desired degree of polymerization, but is generally 0.5 to 20% by weight based on the polymerizable monomer. The kind of the polymerization initiator is slightly different depending on the polymerization method, but is used alone or in combination with reference to the 10-hour half-life temperature.
[0106]
In order to control the degree of polymerization, a known crosslinking agent, chain transfer agent, polymerization inhibitor or the like may be further added and used.
[0107]
When a suspension polymerization method using a dispersion stabilizer is used as a method for producing toner particles, the dispersion stabilizer used is an inorganic compound such as tricalcium phosphate, magnesium phosphate, aluminum phosphate, zinc phosphate, calcium carbonate. , Magnesium carbonate, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, calcium metasilicate, calcium sulfate, barium sulfate, bentonite, silica, alumina and the like. Examples of the organic compound include polyvinyl alcohol, gelatin, methyl cellulose, methyl hydroxypropyl cellulose, ethyl cellulose, sodium salt of carboxymethyl cellulose, polyacrylic acid and its salt, starch and the like. These can be used by dispersing in an aqueous phase. These dispersion stabilizers are preferably used in an amount of 0.2 to 20 parts by weight based on 100 parts by weight of the polymerizable monomer.
[0108]
When an inorganic compound is used as the dispersion stabilizer, a commercially available one may be used as it is, but in order to obtain fine particles, fine particles of the inorganic compound may be generated in a dispersion medium. For example, in the case of tricalcium phosphate, a sodium phosphate aqueous solution and a calcium chloride aqueous solution may be mixed under high-speed stirring.
[0109]
For fine dispersion of these dispersion stabilizers, 0.001 to 0.1 parts by weight of a surfactant may be used in combination. This is to promote the intended action of the above dispersion stabilizer, such as sodium dodecylbenzene sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, sodium oleate, sodium laurate, potassium stearate. , Calcium oleate and the like.
[0110]
When the direct polymerization method is used as a method for producing the toner used in the present invention, the following production method is possible.
[0111]
Addition of colorants, reactive esters and waxes, if necessary, charge control agents, polymerization initiators and other additives to the vinyl monomer, and the polymerizability is uniformly dissolved or dispersed by a homogenizer, ultrasonic disperser, etc. The monomer composition is dispersed in an aqueous medium containing a dispersion stabilizer by a normal stirrer, homomixer, homogenizer or the like. Preferably, granulation is performed by adjusting the stirring speed and stirring time so that the droplets of the polymerizable monomer composition have the desired toner particle size. Thereafter, stirring may be performed to such an extent that the particle state is maintained and the sedimentation of the particles is prevented by the action of the dispersion stabilizer. The polymerization is preferably carried out at a polymerization temperature of 40 ° C. or higher, generally 50 to 90 ° C. The temperature may be raised in the latter half of the polymerization reaction, and for the purpose of improving durability in the image forming method of the present invention, in order to remove the unreacted polymerizable monomer, by-products, etc., or After completion of the reaction, a part of the aqueous medium may be distilled off from the reaction system. After completion of the reaction, the produced toner particles are recovered by washing and filtration and dried. In the suspension polymerization method, it is usually preferable to use 300 to 3000 parts by weight of water as a dispersion medium with respect to 100 parts by weight of the monomer composition.
[0112]
In order to contain a predetermined proportion of component A, component B, and component C with less variation between toner particles, the toner particles must have at least a vinyl monomer, an unsaturated polyester, a colorant, and a polymer containing wax. A monomer composition is dispersed in an aqueous medium to produce particles of a polymerizable monomer composition, and a vinyl monomer in the polymerizable monomer composition is polymerized in the aqueous medium to form a toner. It is good to produce particles. As the vinyl monomer, a styrene monomer, an acrylic ester or a methacrylic ester is preferable. In particular, a combination of a styrene monomer and an acrylic ester or / and a methacrylic ester so that the glass transition point is 40 to 75 ° C. It is good to use.
[0113]
Since the unsaturated polyester in the polymerizable monomer composition has a carboxyl group and a hydroxyl group, it tends to be unevenly distributed on the surface of the particles of the polymerizable monomer composition in the aqueous medium. Unsaturated polyester unevenly distributed on the surface of the particle reacts with a vinyl monomer to produce component B and component C, and the toner particle surface is made so high that it is insoluble in component B and / or THF having a molecular weight of 1 million or more. The toner particles can be formed with the component A containing the wax inside the toner particles. Therefore, it is possible to efficiently generate toner particles that are strong in friction resistance and impact resistance, excellent in durability, and excellent in high temperature offset resistance and low temperature fixability. In order to adjust the ratio of the component B and the component C, the polymerizable monomer composition has a crosslinking agent such as divinylbenzene in an amount of 0.01 to 2.5 parts by weight, more preferably 100 parts by weight of the vinyl monomer. 0.05 to 1.0 part by weight is also preferred. In the toner particles thus produced, the vinyl polymer and the hybrid component in which the vinyl polymer unit and the polyester unit are combined can be unevenly distributed on the toner particle surface. In order to make the hybrid component unevenly distributed on the toner particle surface, the unsaturated polyester preferably has a weight average molecular weight of 3000 to 100,000 (more preferably 3000 to 30,000), and an acid value of 2 to 20 mgKOH / g. The linear polyester is preferred.
[0114]
The toner particles have a BET specific surface area of 50 to 400 m.² / G hydrophobic silica fine powder, hydrophobic titanium oxide fine powder or hydrophobic alumina fine powder is added in an amount of 0.1 to 4.0 parts by weight with respect to 100 parts by weight of toner particles. From the viewpoint of improving environmental stability.
[0115]
Next, an image forming method to which the toner of the present invention is applied will be described below with reference to the accompanying drawings.
[0116]
In the apparatus system shown in FIG. 3, each of the developing devices 4-1, 4-2, 4-3, and 4-4 includes a developer having cyan toner, a developer having magenta toner, a developer having yellow toner, and black. A developer having toner is introduced, and the electrostatic image formed on the electrostatic image carrier (for example, photosensitive drum) 1 is developed by a magnetic brush developing system or a non-magnetic one-component system, and each color toner image is developed on the photosensitive drum. 1 is formed.
[0117]
The toner of the present invention can be mixed with a magnetic carrier and developed using, for example, developing means as shown in FIG. Specifically, it is preferable to perform development in a state where the magnetic brush is in contact with the photosensitive drum 13 while applying an alternating electric field. The distance (S-D distance) B between the developer carrying member (developing sleeve) 11 and the photosensitive drum 13 is 100 to 1000 μm in terms of preventing carrier adhesion and improving dot reproducibility. If it is narrower than 100 μm, the supply of developer tends to be insufficient, and the image density becomes low, and if it exceeds 1000 μm, the magnetic lines from the magnet S 1 spread and the density of the magnetic brush decreases, resulting in poor dot reproducibility and restraining the carrier. This weakens the force to cause carrier adhesion.
[0118]
The voltage (Vpp) between the peaks of the alternating electric field is preferably 500 to 5000 V, and the frequency (f) is 500 to 10000 Hz, preferably 500 to 3000 Hz, and can be appropriately selected and used for each process. In this case, various waveforms such as a triangular wave, a rectangular wave, a sine wave, or a waveform with a changed duty ratio can be selected and used. When the applied voltage is lower than 500 V, it is difficult to obtain a sufficient image density, and the fog toner in the non-image part may not be recovered well. If it exceeds 50000V, the electrostatic image may be disturbed via the magnetic brush, resulting in a decrease in image quality.
[0119]
By using a two-component developer with well-charged toner, the anti-fogging voltage (Vback) can be lowered and the primary charge of the photoreceptor can be lowered, thus extending the life of the photoreceptor. it can. Vback is 150 V or less, more preferably 100 V or less, although it depends on the development system.
[0120]
The contrast potential is preferably 200 V to 500 V so that a sufficient image density can be obtained.
[0121]
If the frequency is lower than 500 Hz, although it is related to the process speed, charge injection into the carrier occurs, so that the image quality may be deteriorated by carrier adhesion or by disturbing the latent image. If it exceeds 10,000 Hz, the toner cannot follow the electric field, and the image quality is liable to deteriorate.
[0122]
The contact width (development nip C) of the magnetic brush on the developing sleeve 11 with the photosensitive drum 13 is preferably 3 to 8 mm in order to achieve a sufficient image density, excellent dot reproducibility, and development without carrier adhesion. Is to do. If the development nip C is narrower than 3 mm, it is difficult to satisfactorily satisfy a sufficient image density and dot reproducibility. If the development nip C is wider than 8 mm, developer packing occurs and the operation of the machine stops or the carrier adheres. It becomes difficult to suppress enough. As a method for adjusting the developing nip, the nip width is appropriately adjusted by adjusting the distance A between the developer regulating member 18 and the developing sleeve 11 or by adjusting the distance B between the developing sleeve 11 and the photosensitive drum 13.
[0123]
In the output of a full color image that emphasizes halftones in particular, three or more developing units for magenta, cyan, and yellow are used, and in particular, a digital latent image is obtained using the developer and development method of the present invention. By combining with the formed development system, it is possible to develop the dot latent image faithfully without being affected by the magnetic brush and without disturbing the latent image. Also in the transfer step, a high transfer rate can be achieved by using the toner of the present invention. Therefore, high image quality can be achieved in both the halftone part and the solid part.
[0124]
Furthermore, by using the toner of the present invention in combination with the improvement of the initial image quality, the effect of the present invention can be sufficiently exerted even when a large number of copies are made, without image quality deterioration.
[0125]
The toner of the present invention can also be suitably used for one-component development. An example of an apparatus for developing an electrostatic image formed on an electrostatic charge image carrier is shown, but is not necessarily limited thereto.
[0126]
In FIG. 5, reference numeral 25 denotes an electrostatic charge image carrier (photosensitive drum), and latent image formation is formed by electrophotographic process means or electrostatic recording means. Reference numeral 24 denotes a toner carrier (developing sleeve), which is a non-magnetic sleeve made of aluminum, stainless steel or the like.
[0127]
The substantially right half circumferential surface of the developing sleeve 24 is always in contact with the toner reservoir in the toner container 21, and the toner in the vicinity of the developing sleeve surface is applied to the developing sleeve surface by the magnetic force of the magnetic generating means in the sleeve and / or by electrostatic force. Adhesion is retained.
[0128]
In the present invention, the surface roughness Ra (μm) of the toner carrier is set to be 1.5 or less. Preferably it is 1.0 or less. More preferably, it is 0.5 or less.
[0129]
By controlling the surface roughness Ra to 1.5 or less, the toner carrying ability of the toner carrying member is suppressed, the toner layer on the toner carrying member is thinned, and the toner carrying member and the toner are separated from each other. Since the number of times of contact is increased, the chargeability of the toner is also improved, so that the image quality is synergistically improved.
[0130]
If the surface roughness Ra of the toner carrier exceeds 1.5, it is difficult not only to make the toner layer on the toner carrier thin, but also the chargeability of the toner is not improved, so that improvement in image quality cannot be expected. .
[0131]
In the present invention, the surface roughness Ra of the toner carrier is measured using a surface roughness measuring instrument (Surfcoder SE-30H, manufactured by Kosaka Laboratory Co., Ltd.) based on JIS surface roughness “JIS B 0601”. This corresponds to the centerline average roughness. Specifically, a 2.5 mm portion as the measurement length a is extracted from the roughness curve in the direction of the center line, the center line of this extraction portion is the X axis, the direction of the vertical magnification is the Y axis, and the roughness curve is When expressed by y = f (x), it means a value obtained by the following formula expressed in micrometers (μm).
[0132]
[Outside 8]

[0133]
As the toner carrier used in the present invention, for example, a cylindrical or belt-like member made of stainless steel, aluminum or the like is preferably used. If necessary, the surface may be coated with a metal, a resin, or the like, or a resin in which fine particles such as a resin, a metal, carbon black, or a charge control agent are dispersed may be coated.
[0134]
In the present invention, by setting the surface movement speed of the toner carrier to be 1.05 to 3.0 times the surface movement speed of the electrostatic charge image carrier, the toner layer on the toner carrier has an appropriate amount. Therefore, the faithful reproduction of the electrostatic latent image is further improved.
[0135]
When the surface moving speed of the toner carrying member is less than 1.05 times the surface moving speed of the electrostatic latent image carrying member, the stirring effect received by the toner layer becomes insufficient, and good image formation cannot be expected. . In addition, when developing an image that requires a large amount of toner over a wide area, such as a solid black image, the amount of toner supplied to the electrostatic latent image is insufficient and the image density becomes low. On the other hand, if it exceeds 3.0, in addition to the various problems caused by excessive charging of the toner as described above, toner deterioration due to mechanical stress and toner adhesion to the toner carrier are generated and promoted, which is not preferable. .
[0136]
The toner T is stored in the hopper 21 and is supplied onto the developing sleeve by the supply member 22. As the supply member, a supply roller made of a foamed material such as a porous elastic body, for example, a flexible polyurethane foam is preferably used. The supply roller is rotated relative to the developing sleeve at a relative speed other than 0 in the forward or reverse direction, and the toner (undeveloped toner) after development on the sleeve is peeled off along with the supply of toner onto the developing sleeve. At this time, the contact width of the supply roller to the developing sleeve is preferably 2.0 to 10.0 mm and more preferably 4.0 to 6.0 mm in consideration of the balance between toner supply and stripping. On the other hand, excessive stress is applied to the toner, and the toner tends to increase in aggregation due to the deterioration of the toner or to be fused and fixed to the developing sleeve, supply roller, etc. The toner used in the developing method of the present invention Is excellent in fluidity and releasability, and has durability stability, so that it is also preferably used in a developing method having the supply member. Moreover, you may use the brush member which consists of resin fibers, such as nylon and rayon, as a supply member. These supply members are extremely effective in a one-component developing method using a non-magnetic one-component toner that cannot use a magnetic binding force, but may be used in a one-component developing method using a magnetic one-component toner.
[0137]
The toner supplied onto the developing sleeve is uniformly applied in a thin layer by the regulating member. The toner thinning regulating member is a doctor blade such as a metal blade or a magnetic blade disposed with a certain gap from the developing sleeve. Alternatively, instead of the doctor blade, a rigid roller or sleeve using metal, resin, ceramic or the like may be used, and magnetism generating means may be placed inside them.
[0138]
Further, an elastic body such as an elastic blade or an elastic roller for press-applying toner may be used as a toner thinning regulating member. For example, in FIG. 5, the elastic blade 23 is fixedly held at its base, which is the upper side, on the developer container 21 side, and the lower side is bent in the forward or reverse direction of the developing sleeve 24 against the elasticity of the blade. The blade inner surface side (or the outer surface side in the reverse direction) is brought into contact with the surface of the sleeve 24 with an appropriate elastic pressure. According to such an apparatus, it is possible to obtain a dense toner layer that is stable against environmental changes. The reason is not necessarily clear, but it is presumed that charging is always performed in the same state regardless of a change in behavior of the toner due to an environmental change because the elastic body forcibly rubs against the surface of the developing sleeve.
[0139]
On the other hand, the toner tends to be excessively charged and the toner is likely to be fused on the developing sleeve or the elastic blade. However, the toner used in the present invention is preferably used because it has a stable releasability and a triboelectric charging property.
[0140]
For the elastic body, it is preferable to select a triboelectric material suitable for charging the toner to a desired polarity, such as a rubber elastic body such as silicone rubber, urethane rubber or NBR; a synthetic resin elastic body such as polyethylene terephthalate. A metal elastic body such as stainless steel, steel or phosphor bronze can be used. Moreover, those composites may be sufficient.
[0141]
Further, when durability is required for the elastic body and the toner carrying body, it is preferable that the metal elastic body is bonded or coated with a resin or rubber so as to contact the sleeve contact portion.
[0142]
Furthermore, an organic substance or an inorganic substance may be added to the elastic body, and it may be melt-mixed or dispersed. For example, the chargeability of the toner can be controlled by adding a metal oxide, metal powder, ceramics, carbon allotrope, whisker, inorganic fiber, dye, pigment, surfactant or the like. In particular, when the elastic body is a molded body such as rubber or resin, fine metal oxide powders such as silica, alumina, titania, tin oxide, zirconia oxide and zinc oxide, carbon black, and a charge control agent generally used for toners Etc. are also preferably contained.
[0143]
In addition, by applying a DC electric field and / or an AC electric field to the developing blade that is the regulating member, the supply roller that is the feeding member, and the brush member, Uniform thin layer coatability and uniform chargeability are further improved, and toner supply / peeling is performed more smoothly at the supply site, so that a sufficient image density can be achieved and a high-quality image can be obtained.
[0144]
The contact pressure between the elastic body and the toner carrier is 0.1 kg / m or more, preferably 0.3 to 25 kg / m, more preferably 0.5 to 12 kg as the linear pressure in the generatrix direction of the toner carrier. / M is effective. As a result, toner aggregation can be effectively loosened, and the toner charge amount can be instantaneously increased. When the contact pressure is less than 0.1 kg / m, it is difficult to uniformly apply the toner, and the toner charge amount distribution becomes broad, causing fog and scattering. On the other hand, if the contact pressure exceeds 25 kg / m, a large pressure is applied to the toner, which is not preferable because the toner deteriorates or toner aggregates are generated. Further, it is not preferable because a large torque is required to drive the toner carrier.
[0145]
The gap α between the electrostatic image carrier and the toner carrier is preferably set to 50 to 500 μm, and the gap between the doctor blade and the toner carrier is preferably set to 50 to 400 μm.
[0146]
The layer thickness of the toner layer on the toner carrier is most preferably smaller than the gap α between the electrostatic image carrier and the toner carrier. The thickness of the toner layer may be regulated to such an extent that the portion contacts the electrostatic charge image carrier.
[0147]
On the other hand, an alternating electric field is applied to the toner carrier from the electrostatic charge image carrier by the bias power source 26, thereby facilitating the movement of the toner from the toner carrier to the electrostatic image carrier. Can be obtained. Vpp of the alternating electric field is 100V or more, preferably 200 to 3000V, more preferably 300 to 2000V. Further, f is 500 to 5000 Hz, preferably 1000 to 3000 Hz, more preferably 1500 to 3000 Hz. In this case, a waveform such as a rectangular wave, a sine wave, a sawtooth wave, and a triangular wave can be applied. Also, asymmetrical AC bias with different forward and reverse voltages and time can be used. It is also preferable to superimpose a DC bias.
[0148]
The electrostatic image carrier 1 is a-Se, Cds, ZnO.₂ , OPC, a photosensitive drum or photosensitive belt having a photoconductive insulating material layer such as a-Si. The electrostatic image carrier 1 is rotated in the direction of the arrow by a driving device (not shown).
[0149]
As the electrostatic charge image carrier 1, a photoreceptor having an amorphous silicon photosensitive layer or an organic photosensitive layer is preferably used.
[0150]
The organic photosensitive layer may be a single layer type in which the photosensitive layer contains a charge generation material and a substance having charge transport performance in the same layer, or a function-separated type photosensitive layer having the charge generation layer as a component. It may be. A laminated photosensitive layer having a structure in which a charge generation layer and then a charge transport layer are laminated in this order on a conductive substrate is one preferred example.
[0151]
The binder resin for the organic photosensitive layer is particularly a polycarbonate resin, a polyester resin, or an acrylic resin, and has good transferability and cleaning properties, and poor cleaning, toner fusion to the photoreceptor, and filming of external additives are unlikely to occur.
[0152]
In the charging process, there are a non-contact type with the electrostatic image carrier 1 using a corona charger and a contact type using a roller or the like, and either one is used. For efficient uniform charging, simplification, and low ozone generation, a contact type as shown in FIG. 1 is preferably used.
[0153]
The charging roller 2 is basically composed of a central core metal 2b and a conductive elastic layer 2a that forms the outer periphery thereof. The charging roller 2 is pressed against the surface of the electrostatic image carrier 1 with a pressing force, and is driven to rotate as the electrostatic image carrier 1 rotates.
[0154]
As a preferable process condition when the charging roller is used, when the contact pressure of the roller is 5 to 500 g / cm and an AC voltage is superimposed on the DC voltage, the AC voltage is 0.5 to 5 kVpp, and AC The frequency is 50 Hz to 5 kHz, the DC voltage is ± 0.2 to ± 1.5 kV, and when only the DC voltage is used, the DC voltage is ± 0.2 to ± 5 kV.
[0155]
Other charging means include a method using a charging blade and a method using a conductive brush. These contact charging means are effective in that a high voltage is unnecessary and generation of ozone is reduced.
[0156]
The material of the charging roller and charging blade as the contact charging means is preferably conductive rubber, and a release coating may be provided on the surface thereof. As the releasable coating, nylon resin, PVDF (polyvinylidene fluoride), PVDC (polyvinylidene chloride), and the like are applicable.
[0157]
The toner image on the electrostatic image carrier is transferred to the intermediate transfer member 5 to which a voltage (for example, ± 0.1 to ± 5 kV) is applied. The surface of the electrostatic image carrier is cleaned by a cleaning unit 9 having a cleaning blade 8.
[0158]
The intermediate transfer member 5 includes a pipe-shaped conductive core 5b and a medium-resistance elastic layer 5a formed on the outer peripheral surface thereof. The core 5b may be a plastic pipe with conductive plating.
[0159]
Medium resistance elastic layer 5a is made of elastic material such as silicone rubber, Teflon rubber, chloroprene rubber, urethane rubber, EPDM (terpolymer of ethylene propylene diene), carbon black, zinc oxide, tin oxide, silicon carbide. The electrical conductivity value (volume resistivity) is 10 by mixing and dispersing a conductivity imparting material such as^Five -10¹¹Solid or foamed layer adjusted to medium resistance of Ω · cm.
[0160]
The intermediate transfer member 5 is disposed in parallel with the electrostatic charge image carrier 1 so as to be in contact with the lower surface portion of the electrostatic charge image carrier 1 and has an arrow at the same peripheral speed as the electrostatic charge image carrier 1. Rotate counterclockwise.
[0161]
The first color toner image formed and supported on the surface of the electrostatic charge image carrier 1 is applied to the intermediate transfer member 5 in the process of passing through the transfer nip where the electrostatic charge image carrier 1 and the intermediate transfer member 5 are in contact with each other. The intermediate transfer is sequentially performed on the outer surface of the intermediate transfer member 5 by an electric field formed in the transfer nip region by the bias.
[0162]
If necessary, the surface of the intermediate transfer member 5 is cleaned by the removable cleaning means 10 after the transfer of the toner image onto the transfer material. When there is a toner image on the intermediate transfer member, the cleaning means 10 is separated from the surface of the intermediate transfer member so as not to disturb the toner image.
[0163]
A transfer means is disposed in parallel with the intermediate transfer body 5 and brought into contact with the lower surface of the intermediate transfer body 5. The transfer means 7 is, for example, a transfer roller or a transfer belt, and has the same circumference as the intermediate transfer body 5. Rotates clockwise at the speed of the arrow. The transfer unit 7 may be disposed so as to be in direct contact with the intermediate transfer member 5, or a belt or the like may be disposed between the intermediate transfer member 5 and the transfer unit 7.
[0164]
In the case of a transfer roller, the basic configuration is a central core 7b and a conductive elastic layer 7a that forms the outer periphery thereof.
[0165]
Common materials can be used for the intermediate transfer member and the transfer roller. By setting it smaller than the volume resistivity of the elastic layer of the intermediate transfer member, the voltage applied to the transfer roller can be reduced, and a good toner image can be formed on the transfer material and the transfer material can be wrapped around the intermediate transfer member. Can be prevented. In particular, the volume specific resistance value of the elastic layer of the intermediate transfer member is particularly preferably 10 times or more than the volume specific resistance value of the elastic layer of the transfer roller.
[0166]
For example, the conductive elastic layer 7b of the transfer roller 7 has a volume resistance 10 such as polyurethane, ethylene-propylene-diene terpolymer (EPDM) in which a conductive material such as carbon is dispersed.⁶ -10^TenMade of Ω · cm elastic body. A bias is applied to the cored bar 7a by a constant voltage power source. The bias condition is preferably ± 0.2 to ± 10 kV.
[0167]
The toner of the present invention has a high transfer efficiency in the transfer process, a small amount of residual toner, and an excellent cleaning property, so that it is difficult to cause filming on the electrostatic charge image carrier. Further, even when a multi-sheet durability test is performed, the toner of the present invention is less likely to be buried in the surface of the toner particles than the conventional toner, so that good image quality can be maintained over a long period of time. In particular, it is preferably used in an image forming apparatus having a so-called loose mechanism in which transfer residual toner on an electrostatic charge image carrier or intermediate transfer member is removed by a cleaning means such as a cleaning blade, and the recovered transfer residual toner is reused.
[0168]
Next, the toner image on the transfer material 6 is fixed by a heat and pressure fixing means. As a heating and pressure fixing means, there is a heating roller method including a heating roller containing a heating element such as a halogen heater and an elastic pressing roller pressed against the heating roller, or a heater via a film. There is a heat fixing method (FIGS. 4 and 5). Since the toner of the present invention is excellent in fixability and offset resistance, it exhibits good matching with the heat and pressure fixing means as described above.
[0169]
Hereinafter, the present invention will be described with reference to specific examples, but the present invention is not limited thereto.
[0170]
Example 1
132 parts by weight of styrene, 68 parts by weight of n-butyl acrylate, 0.91 part by weight of divinylbenzene (purity 55%), 4.0 parts by weight of the following linear unsaturated polyester, paraffin wax (endothermic main peak 75 ° C., several Average molecular weight 830) 20 parts by weight, carbon black (BET specific surface area = 60 m² / G, oil absorption = 115 ml / g) 15 parts by weight, 4.0 parts by weight of negative charge control agent (iron complex of di-tert-butylsalicylic acid) is sufficient using an attritor (Mitsui Miike Koki Co., Ltd.) Mixed and dispersed.
[0171]
Linear unsaturated polyester:
(A) A polycondensate of the following fumaric acid and the following bisphenol A derivative.
[0172]
[Outside 9]

(B) Weight average molecular weight: 10,000
(C) Acid value: 10 (mgKOH / g)
[0173]
Further, 10 parts by weight of 2,2'-azobis (2,4-dimethylvaleronitrile) was added and stirred well to prepare a polymerizable monomer composition.
[0174]
On the other hand, 500 parts by weight of ion-exchanged water and 0.1 M Na in a four-necked vessel equipped with a high-speed stirring device TK type homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.)_Three PO_Four  650 parts by weight of the aqueous solution was added and heated to 70 ° C. Here, 1.0M CaCl₂ 100 parts by weight of an aqueous solution, and stirred at a rotational speed of 10000 rpm, the fine hardly water-soluble dispersion stabilizer Ca_Three (PO_Four )₂ An aqueous medium containing was prepared.
[0175]
The polymerizable monomer composition was put into an aqueous medium and granulated by continuing stirring at 10,000 rpm for 7 minutes while maintaining the temperature at 70 ° C. under a nitrogen stream. Thereafter, the stirring was switched to a paddle type stirring blade, and polymerization was carried out at 70 ° C. for 5 hours and at 80 ° C. for 5 hours.
[0176]
After the completion of the polymerization reaction, the contents in the container were cooled to room temperature, hydrochloric acid was added to dissolve the hardly water-soluble dispersion stabilizer, and toner particles (A) were obtained through filtration, washing with water and drying. As shown in FIG. 2A, the toner particles (A) were substantially spherical and dispersed in a state where the wax was not compatible with the binder resin. Further, the ester component was unevenly distributed on the surface of the toner particles (A). The toner particles (A) thus obtained were about 10 parts by weight of parein wax with respect to 100 parts by weight of a binder resin having a styrene-n-butyl acrylate copolymer crosslinked with divinylbenzene and an unsaturated polyester unit. About 7.5 parts by weight of carbon black and about 2 parts by weight of negative charge control agent were contained. The unsaturated polyester reacted with styrene and n-butyl acrylate to form a hybrid component. The physical properties of the toner particles are shown in Tables 1-3.
[0177]
Hydrophobic silica fine powder (BET; specific surface area 200 m) to 100 parts by weight of the toner particles (A)² / G) After adding 2.0 parts by weight of the toner (A) of the present invention, the toner (A) 6.0 parts by weight and a silicone resin-coated magnetic ferrite carrier (average particle size: 50 μm) 94 parts by weight The two-component developer (A) for magnetic brush development was prepared by mixing the part.
[0178]
Example 2
Toner particles (B) were produced in the same manner as in Example 1 except that 4 parts by weight of the following saturated polyester was further added to the polymerizable monomer composition of Example 1.
[0179]
Saturated polyester:
(A) A polycondensate of the following terephthalic acid and the following bisphenol A derivative.
[0180]
[Outside 10]

(B) Weight average molecular weight: 11,000
(C) Acid value: 12 (mgKOH / g)
[0181]
Further, a toner (B) and a developer (B) were prepared in the same manner as in Example 1.
[0182]
Example 3
The toner particles (C), the toner (C), the toner (C), the toner polyester (C), the toner polyester (C), and the toner polyester (C), except that the amount of saturated polyester is 10 parts by weight and the amount of divinylbenzene (purity 55%) is 0.30 parts by weight. Developer (C) was obtained.
[0183]
Example 4
Toner particles (D), toner (D), and developer (D) were obtained in the same manner as in Example 3 except that the addition amounts of the unsaturated polyester and saturated polyester were 5 parts by weight and 15 parts by weight, respectively. .
[0184]
Example 5
Toner particles (E), toner (E), and developer (E) were obtained in the same manner as in Example 3 except that the addition amounts of the unsaturated polyester and saturated polyester were 6 parts by weight and 20 parts by weight, respectively. .
[0185]
Example 6
Toner particles (F), toner (F) and development were carried out in the same manner as in Example 1 except that the amount of divinylbenzene (purity 55%) was 1.8 parts by weight and the polymerization reaction was carried out at 60 ° C. for 10 hours. Agent (F) was obtained.
[0186]
Comparative Example 1
Comparative toner particles (G), comparative toner (G), and comparative developer (G) were used in the same manner as in Example 1 except that 20 parts by weight of the saturated polyester used in Example 2 was used without using unsaturated polyester. )
[0187]
Comparative Example 2
The addition amount of divinylbenzene (purity 55%) is 5.0 parts by weight, the addition amount of 2,2′-azobis (2,4-dimethylvaleronitrile) is 2 parts by weight, and the polymerization reaction is performed at 50 ° C. for 5 hours. A comparative toner particle (H), a comparative toner (H), and a comparative developer (H) were obtained in the same manner as in Example 1 except that the process was performed at 60 ° C. for 5 hours.
[0188]
Comparative Example 3
・ Styrene-butyl acrylate copolymer 100 parts by weight
(Peak molecular weight 2 million, MW = 32,000, Mw / Mn = 1.8, Tg = 59 ° C.)
-2 parts by weight of unsaturated polyester used in Example 1
-7.5 parts by weight of carbon black used in Example 1
-2 parts by weight of negative charge control agent used in Example 1
-10 parts by weight of paraffin wax used in Example 1
[0189]
The above mixture was melt-kneaded with a biaxial extruder, the cooled kneaded product was coarsely pulverized with a hammer mill, the coarsely pulverized product was finely pulverized with a jet mill, and classified to obtain comparative toner particles (I). Comparative toner (I) and comparative developer (I) were obtained using comparative toner particles (I) in the same manner as in Example 1.
[0190]
The wax component in the comparative toner particles (I) was in a finely dispersed state as shown in FIG. 2B, and wax was also confirmed on the toner particle surfaces.
[0191]
Tables 1 to 3 show physical particle size distributions, shape factor measurement results, and TEM observation results of toner particles (A) to (F) and comparative toner particles (G) to (I).
[0192]
[Table 1]

[0193]
[Table 2]

[0194]
[Table 3]

[0195]
Examples 7-12 and Comparative Examples 4-6
Each development prepared in Examples 1 to 6 and Comparative Examples 1 to 3 was put in a black developing device shown in FIG. 3, and an image output test was performed in a single color mode.
[0196]
The image forming apparatus used will be described with reference to FIG.
[0197]
The photosensitive drum 1 has a sightseeing layer 1b having an organic optical semiconductor on a substrate 1a, and is photosensitive by a charging roller 2 (conductive elastic layer 2a, cored bar 2b) that rotates in the direction of an arrow and rotates against and in contact. The body drum 1 was charged to a surface potential of about −600V. In exposure 3, a digital electrostatic charge image having an exposed portion potential of −100 V and a dark portion potential of −600 V was formed on a photoconductor by a polygon mirror according to digital image information. The developing unit 4-4 was used to develop an electrostatic image on the photoreceptor 1 by a reversal development method, thereby obtaining a black toner image. The toner image is transferred onto the intermediate transfer member 5 (elastic layer 5a, cored bar 5b as a support), and toner is formed on the intermediate transfer member 5. The transfer residual toner on the photoreceptor 1 was collected in the residual toner container 9 by the cleaner member 8.
[0198]
The intermediate transfer member 5 was coated on a pipe-shaped metal core 5b with an elastic layer 5b in which a carbon black conductivity imparting member was sufficiently dispersed in nitrile-butadiene rubber (NBR). The hardness of the coat layer 5b is 30 degrees according to “JIS K-6301” and the volume resistivity is 10⁹ It was Ω · cm. The transfer current required for transfer from the photosensitive member 1 to the intermediate transfer member 5 is about 5 μA, which was obtained by applying +500 V from the power source to the core metal 5b.
[0199]
The core 7b having an outer diameter of 20 mm and a diameter of 10 mm of the transfer roller 7 is coated with a carbon conductive imparting member sufficiently dispersed in an ethylene-propylene-diene terpolymer (EPDM) foam. The elastic layer 7a is produced by the above process, and the volume resistivity value of the elastic layer 7a is 10⁶ The standard hardness of “JIS K-6301” in Ω · cm was 35 degrees. A voltage was applied to the transfer roller to pass a transfer current of 15 μA.
[0200]
As the heat and pressure fixing device H, a heat roll type fixing device having no oil application function was used. At this time, both the upper roller and the lower roller had a fluororesin surface layer, and the roller had a diameter of 60 mm. The fixing temperature was 150 ° C., and the nip width was set to 7 mm.
[0201]
Under the above setting conditions, developer (A) at a printout speed of 8 sheets (A4 size) / min in an environment of normal temperature and normal humidity (25 ° C., 60% RH) and high temperature and high humidity (30 ° C., 80% RH). In each of (I) to (I), a printout test is performed in a continuous mode in a single color while supplying black toner sequentially (that is, a mode in which toner consumption is promoted without pausing the developing device), and the resulting printout is obtained. Images were evaluated for items described below.
[0202]
Further, matching between the image forming apparatus used at the same time and the developer was also evaluated.
[0203]
The residual toner collected by the cleaning was transported to the developing device by the loose mechanism and reused.
[0204]
Next, the fixing device was removed, the external driving device was attached, the fixing roller was rotated at 150 mm / second, the temperature control device was attached, and the fixing roller temperature was changed within the range of 100 to 230 ° C.
[0205]
In the fixing test, after the upper roller (heating roller) reaches the specified temperature, hold that temperature for another 10 minutes, and confirm that the lower roller (pressure roller) is heated sufficiently and the temperature becomes constant. I went there.
[0206]
The above evaluation results are shown in Tables 4 and 5.
[0207]
[Table 4]

[0208]
[Table 5]

[0209]
[Printout image evaluation]
<1> Image density
Ordinary paper for ordinary copying machines (75 g / m² ) Was evaluated by maintaining the image density when a predetermined number of printouts were completed. The image density was measured by using a “Macbeth reflection densitometer” (manufactured by Macbeth Co., Ltd.) to measure a relative density with respect to a printout image of a white background portion having a document density of 0.00.
A: Very good (above 1.40)
B: Good (1.35 to less than 1.40)
C: Normal (from 1.00 to less than 1.35)
D: Bad (less than 1.00)
[0210]
<2> Image fog
The fog density (%) was calculated from the difference between the whiteness of the white portion of the printout image measured by “Reflectometer” (manufactured by Tokyo Denshoku Co., Ltd.) and the whiteness of the transfer paper, and the image fogging was evaluated.
A: Very good (less than 1.5%)
B: Good (1.5% or more to less than 2.5%)
C: Normal (2.5% or more to less than 4.0%)
D: Poor (4% or more)
[0211]
<3> Fixing property
Fixability is 50 g / cm² The fixed image was rubbed with a soft thin paper, and the reduction rate (%) of the image density before and after rubbing was evaluated.
A: Very good (less than 5%)
B: Good (5% or more to less than 10%)
C: Normal (between 10% and less than 20%)
D: Bad (more than 20%)
[0212]
<4> Offset resistance
The offset resistance was evaluated based on the degree of contamination on an image after 3000 sheets of a sample image having an image area ratio of about 5%.
A: Very good (not generated)
B: Good (almost no occurrence)
C: Normal
D: Bad
[0213]
<5> Minimum fixing temperature
50 g / cm² Lens cleaning paper (lens cleaning paper (“Dusper” (trade name), mfd.by OZU paper Co. Ltd.)) rubs the fixed image 10 times and decreases the image density before and after rubbing. The lowest fixing temperature at which the rate is 20% or less is defined as the minimum fixing temperature.
[0214]
<6> High temperature resistant offset temperature
The presence or absence of high temperature offset is judged visually, and the highest fixing temperature at which high temperature offset does not occur is defined as the high temperature offset temperature.
[0215]
[Image forming device matching evaluation]
<1> Matching with developing sleeve
After completion of the printout test, the appearance of residual toner on the surface of the developing sleeve and the influence on the printout image were visually evaluated.
A: Very good (not generated)
B: Good (almost no occurrence)
C: Normal (there is sticking, but there is little influence on the image)
D: Poor (much sticking and causes image unevenness)
[0216]
<2> Matching with photosensitive drum
After completion of the printout test, the occurrence of scratches on the surface of the photosensitive drum and the sticking of residual toner and the influence on the printout image were visually evaluated.
A: Very good (not generated)
B: Good (slight scratches are seen, but there is little effect on the image)
C: Normal (there is sticking or scratching, but there is little effect on the image)
D: Poor (there is much sticking and causes vertical stripe-like image defects)
[0217]
<3> Matching with intermediate transfer member
After completion of the printout test, scratches on the surface of the intermediate transfer member and the adhesion state of the residual toner were visually evaluated.
A: Very good (not generated)
B: Good (the presence of residual toner is recognized on the surface, but there is no influence on the image)
C: Normal (there is sticking or scratching, but there is little effect on the image)
D: Poor (much sticking and causes image defects)
[0218]
<4> Matching with fixing device
After completion of the printout test, scratches on the surface of the fixing film and the fixing state of the residual toner were visually evaluated.
A: Very good (not generated)
B: Good (although slight fixation is observed, there is no influence on the image)
C: Normal (there is sticking or scratching, but there is little effect on the image)
D: Poor (much sticking and causes image defects)
Example 13 and Comparative Example 7
[0219]
The developing device of the image forming apparatus shown in FIG. 3 is replaced with the one shown in FIG. 5, and the moving speed of the toner carrier surface is set to be 3.0 times the moving speed of the electrostatic latent image carrier surface. While the toner (A) and the comparative toner (G) are sequentially replenished, the monochromatic intermittent mode (that is, the developing device is paused for 10 seconds every time one sheet is printed out, and the developing device is preliminarily operated upon restarting. The mode was evaluated in the same manner as in the previous example.
[0220]
The toner carrier used here has a surface roughness Ra of 1.5, and the toner regulating blade is made by bonding urethane rubber to a phosphor bronze base plate and coating the contact surface with the toner carrier with nylon. It was. 6 and 7 is used as the heat fixing device H, the surface temperature of the temperature detecting element 31d of the heating member 31 is 130 ° C., and the sponge 21 having a heating member 21-silicon rubber foam as a lower layer is used. The total pressure between the pressure rollers 33 is 8 kg, the nip between the pressure roller and the film is 6 mm, and the fixing film 32 has a low resistance in which a conductive substance is dispersed in PTEF (high molecular weight type) on the contact surface with the transfer material. A heat-resistant polyimide film having a thickness of 60 μm and having a release layer was used. The above evaluation results are shown in Table 6.
[0221]
[Table 6]

[0222]
Example 14 and Comparative Example 8
A commercially available laser beam printer LBP-EX (manufactured by Canon Inc.) was used with a Ruth mechanism attached and modified. Specifically, in FIG. 8, after the untransferred toner on the photosensitive drum 60 is scraped off by the elastic blade 62 of the cleaner 61 in contact with the photosensitive drum, it is sent into the cleaner by the cleaner roller, and further the cleaner screw. After passing through 63, the supply pipe 64 provided with a conveying screw is returned to the developing device 26 through the hopper 65, and a system using the collected toner is attached again, and the conductive carbon coated with nylon resin as the primary charging roller 67. Using a rubber roller (diameter: 12 mm, contact pressure: 50 g / cm) in which the electrostatic latent image bearing member is subjected to laser exposure (600 dpi) to dark part potential V_D = -700V, light potential V_L = -200V was formed. The developing sleeve 68 having a surface roughness Ra of 1.1 coated with a resin in which carbon black is dispersed on the surface as a toner carrier is set to be 1.1 times the moving speed of the photosensitive drum surface, Next, the gap (between S and D) between the photosensitive drum and the developing sleeve was 270 μm, and a urethane rubber blade was used as a toner regulating member. As a developing bias, an AC bias component is superimposed on a DC bias component. The set temperature of the heat fixing device was 150 ° C.
[0223]
Under the above setting conditions, toner (A) is printed at a printout speed of 12 sheets (A4 size) / min in an environment of normal temperature and normal humidity (25 ° C., 60% RH) and high temperature and high humidity (30 ° C., 80% RH). In the intermittent mode (that is, the mode in which the developing device is paused for 10 seconds every time one sheet is printed and the deterioration of the toner is promoted by the preliminary operation during the re-orbit) while sequentially supplying each of the comparative toners (G). A printout test was conducted, and the obtained printout images were evaluated for the items described below.
[0224]
The matching between the image forming apparatus used at the same time and the toner was also evaluated.
[0225]
The above evaluation results are shown in Table 7.
[0226]
[Table 7]

[0227]
Example 15
8 except that the toner reuse mechanism is removed and the printout speed is set to 16 sheets (A4 size) / min. A printout test was conducted in a mode that promotes toner consumption without pausing.
[0228]
The obtained printout image was evaluated for the items described below, and the matching with the image forming apparatus used was also evaluated. As a result, all items were good.
[0229]
Example 16
In Example 3, instead of carbon black, 6 parts by weight of a yellow colorant (CI Pigment Yellow 13), 6 parts by weight of a magenta colorant (CI Pigment Red 57: 1), a cyan colorant (C Pigment Blue 15: 3) Yellow toner particles, magenta toner particles, and cyan toner particles were respectively prepared using 6 parts by weight.
[0230]
Tables 8 to 10 show the physical properties of the toner particles.
[0231]
In the same manner as in Example 1, yellow toner, magenta toner, cyan toner, yellow developer, magenta developer, and cyan developer were prepared and placed in developing units 4-1, 4-2, and 4-3, respectively. Using the developer 4-4 containing 1 developer [toner (A)], an image output test was conducted in the full color mode. Even with oilless fixing, it was found that a clear full-color image was obtained without causing an offset and had sufficient mixing properties.
[0232]
[Table 8]

[0233]
[Table 9]

[0234]
[Table 10]

[0235]
【The invention's effect】
As described above, according to the present invention, extremely good low-temperature fixability and offset resistance can be compatible, and a high-quality image can be formed over a long period of time. Furthermore, matching with the image forming apparatus is also suitable.
[Brief description of the drawings]
1 is a GPC chromatogram of a THF soluble component of toner particles (A) produced in Example 1. FIG.
FIG. 2 is a schematic diagram showing an example of a cross section of toner particles in which wax is dispersed inside the toner particles.
FIG. 3 is a schematic explanatory diagram of an example of an image forming apparatus suitable for the image forming method of the present invention.
FIG. 4 is an enlarged cross-sectional view of a main part of a developing device for a two-component developer used in an embodiment of the present invention.
FIG. 5 is an enlarged cross-sectional view of a main part of a developing device for a one-component developer used in an embodiment of the present invention.
FIG. 6 is an exploded perspective view of a main part of the heat and pressure fixing device used in the embodiment of the present invention.
FIG. 7 is an enlarged cross-sectional view of a main part showing a film state when the heat and pressure fixing device used in the example of the present invention is not driven.
FIG. 8 is a schematic explanatory diagram of an example of an image forming apparatus that reuses untransferred toner.
[Explanation of symbols]
1 Photoconductor (electrostatic latent image carrier)
2 Charging roller
3 exposure
4 4-color developing device (4-1, 4-2, 4-3, 4-4)
5 Intermediate transfer member
6 Transfer material
7 Transfer roller
11 Developer carrier
13 Photosensitive drum
30 stays
31 Heating body
31a Heater board
31b Heating element
31c Surface protective layer
31d Temperature sensor
32 Fixing film
33 Pressure roller
34 Coil spring
35 Film edge regulating flange
36 Power connector
37 Power interruption member
38 Entrance guide
39 Exit guide (separation guide)

Claims (41)

An electrostatic charge image developing toner having toner particles containing at least a binder resin, a colorant and a wax;
(I) the binder resin,
i) a hybrid component in which a vinyl polymer unit of a vinyl polymer component and a polyester unit of a polyester component are bonded to each other ;
ii) In the gel permeation chromatography (GPC) chromatogram of the soluble component of tetrahydrofuran (THF),
Containing 42 to 95% by weight of component A which is a low molecular weight component having a molecular weight of less than 1 million and a medium molecular weight component,
2 to 15% by weight of component B, which is a high molecular weight component having a molecular weight of 1 million or more,
The main peak is in the region of molecular weight 3,000-50,000,
iii) containing 3 to 55% by weight of component C, which is a THF-insoluble component,
iv) the total amount of component B and component C is 5 to 58% by weight;
v) The B component contains 0 to 90% by weight of the polyester component (based on the weight of the B component), and the C component contains 0 to 90% by weight of the polyester component (based on the weight of the C component). And the total amount of the B component and the C component polyester component is 0.02 to 90% by weight (based on the total amount of the B component and the C component),
(II) A toner for developing an electrostatic charge image, wherein the toner particle has a shape factor SF-1 of 100 to 160 and a toner particle has a shape factor SF-2 of 100 to 140. The toner according to claim 1, wherein the binder resin contains 0.1 to 20% by weight of a polyester component (based on the weight of the binder resin). The toner according to claim 1, wherein the binder resin contains 0.1 to 10% by weight (based on the weight of the binder resin) of a polyester component. The toner according to claim 1, wherein the binder resin contains 0.1 to 5% by weight of a polyester component (based on the weight of the binder resin). The toner according to any one of claims 1 to 4 , wherein a main peak is in a region having a molecular weight of 3,000 to 40,000 in a GPC chromatogram of a soluble component of THF as a binder resin. In the GPC chromatogram of the soluble components of the THF of the binder resin, any of the toner of claims 1 to 4 main peak is in the molecular weight region of 10,000 to 30,000. A component, any of the toner of claims 1 to 6 having a vinyl polymer component 70% by weight or more (based on the weight of component A). A component, any of the toner of claims 1 to 6 having a vinyl polymer component 85% by weight or more (based on the weight of component A). The binder resin has 2 to 10% by weight of B component (based on the weight of the binder resin), 5 to 45% by weight of C component (based on the weight of the binder resin), and B any of the toner of claims 1 to 8 total amount of component and C component is 7-49 wt%. Toner particles have a weight average particle diameter of 4-8 [mu] m, any of the toner of claims 1 to 9 variation in number distribution coefficient is 35% or less. The toner according to claim 10 , wherein the toner particles have a coefficient of variation in the number distribution of 20 to 30%. Toner particles, a shape factor SF-1 is 100 to 140, any of the toner of claims 1 to 11 shape factor SF-2 is 100 to 120. Any of the toner of claims 1 to 12 wax has an endothermic main peak in the region of the temperature 40 to 150 ° C. in an endothermic curve of DSC. Waxes, one of the toner of claims 1 to 12 having an endothermic main peak in a temperature 50 to 100 ° C. in an endothermic curve of DSC. Any of the toner of claims 1 to 13 vinyl polymer component of the binder resin is crosslinked with a crosslinking agent. Vinyl polymer component styrene - acrylic copolymer component or a styrene - either toner of claims 1 to 15 is a methacrylic copolymer component. The polyester component, any of the toner of claims 1 to 16 having the following bisphenol A derivative unit.
[Outside 1]

(In the formula, R is an ethylene or propylene group, x and y are each an integer of 1 or more, and the average value of x + y is 2 to 10.) The polyester component, any of the toner of claims 1 to 17 and has an unsaturated polyester component having a vinyl unit. Toner particles are produced by dispersing a polymerizable monomer composition containing at least a vinyl monomer, an unsaturated polyester, a colorant and a wax in an aqueous medium to produce particles of the polymerizable monomer composition. any of the toner of claims 1 to 18 has a tree fat particles produced by polymerizing a vinyl monomer in the particles of the polymerizable monomer composition in the medium. The toner according to claim 19 , wherein the unsaturated polyester has a weight average molecular weight of 3000 to 100,000. The toner according to claim 19 or 20 , wherein the unsaturated polyester has an acid value of 2 to 20 mgKOH / g. The toner according to any one of claims 19 to 21 , wherein the unsaturated polyester is a polycondensate of a divalent alcohol component and a divalent dicarboxylic acid component having a vinyl group. The toner of claim 22 dihydric alcohol component is bisphenol A-induced body represented by the following formula (A).
[Outside 2]

(In the formula, R is an ethylene or propylene group, x and y are each an integer of 1 or more, and the average value of x + y is 2 to 10.) 24. The toner according to claim 22 , wherein the divalent dicarboxylic acid having a vinyl group is fumaric acid, and the unsaturated polyester is a linear polyester. Polymerizable monomer composition further any of the toner of claims 19 to 24 containing a saturated polyester. B component, any of the toner of claims 1 to 25 containing a hybrid component and are bonded vinyl polymer unit and an unsaturated polyester unit. Component C, any of the toner of claims 1 to 26 containing a hybrid component in which the vinyl polymer unit and an unsaturated polyester unit bonded. 28. The toner according to any one of claims 1 to 27 , wherein the toner particles include a wax, and the surface of the toner particles contains a hybrid component in which a vinyl polymer unit and an unsaturated polyester unit are combined. Waxes, one of the toner of claims 1 to 28 is contained 2 to 30 wt% in the toner particles. A charging step in which a voltage is applied to the charging member from the outside to charge the electrostatic charge image carrier, a step of forming an electrostatic charge image on the charged electrostatic charge image carrier, and the electrostatic charge image on the toner carrier. Developing with toner to form a toner image on the electrostatic charge image carrier, transfer process for transferring the toner image on the electrostatic charge image carrier to the transfer material, and heating and pressurizing the toner image on the transfer material An image forming method having a fixing step of fixing,
30. An image forming method , wherein the toner is the toner according to any one of claims 1 to 29 . A charging step of applying a voltage to the charging member from the outside to charge the electrostatic image carrier, a step of forming a first electrostatic image on the charged electrostatic image carrier, and a first electrostatic image Developing with the first toner to form a first toner image on the electrostatic charge image carrier, and a first transfer of the first toner image on the electrostatic charge image carrier to the intermediate transfer member A transfer process;
A charging step of applying a voltage to the charging member from the outside to charge the electrostatic charge image carrier, a step of forming a second electrostatic charge image on the charged electrostatic charge image carrier, and a second electrostatic charge image Developing with the second toner to form a second toner image on the electrostatic image carrier, and a first toner image transferred to the intermediate transfer member with the second toner image on the electrostatic image carrier A transfer process;
An image forming method comprising: a second transfer step of transferring a first toner image and a second toner image on an intermediate transfer member onto a transfer material; and a fixing step of heating and fixing the toner image on the transfer material. Yes,
An image forming method, wherein each toner is the toner according to claim 1 . In the developing step, the moving speed of the toner carrier surface in the developing region is 1.05 to 3.0 times the moving speed of the electrostatic charge image carrier surface, and the surface roughness Ra ( 32. The image forming method of claim 30 or 31 , wherein [mu] m) is 1.5 or less. The image forming method according to any one of claims 30 to 32, wherein blades are arranged at minute intervals so as to face the toner carrier. The image forming method according to any one of claims 30 to 32, wherein a blade formed of an elastic body facing the toner carrier is in contact with the toner. Has a fixed gap there is electrostatic charge image bearing member and the toner carrying member, any of the image forming method according to claim 30 or 34 develops the electrostatic image while applying an alternating electric field to the toner carrying member. The image forming method according to claim 30 or 34 toner layer on the toner carrying member to develop the electrostatic image while contacting the electrostatic image-bearing member. The charging step, the charging member is brought into contact with the electrostatic image bearing member, a voltage is applied to from the charging member outside any of the image forming method according to claim 30 or 36 for charging the electrostatic image bearing member. The electrostatic charge image carrier and the transfer device are in contact with each other via the transfer material during a transfer process in which the toner image on the electrostatic image carrier is electrostatically transferred to a transfer material using a transfer device. Item 40. The image forming method according to any one of Items 30 to 37 . Heating pressure fixing process, there is no supply of the liquid for preventing the offset, or by fuser does not have a cleaner heat-pressure fixing device, according to claim heated pressurizing pressure fixing the toner image to the transfer material 30 to 38 Any one of the image forming methods. The heat and pressure fixing step heats and presses the toner image onto the transfer material by a fixedly supported heating body and a pressure member that is in pressure contact with the heating body and is in close contact with the heating body through a film. the image forming method according to claim 30 or 39 for fixing. After the transfer, the untransferred residual toner on the electrostatic image carrier is cleaned and recovered, and the recovered toner is supplied to the developing device and held in the developing device again, and the electrostatic image on the electrostatic image carrier developed, any of the image forming method according to claim 30 or 40 for reuse recovered toner.

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