JP3943786B2 - Toner and image forming method - Google Patents

Description

【００５６】
一般式（１）で表わせるシラン化合物、窒素元素を含有する置換基を有するシランカップリング剤の例として、アミノプロピルトリメトキシシラン、アミノプロピルトリエトキシシラン、ジメチルアミノプロピルトリメトキシシラン、ジメチルアミノプロピルメチルジエトキシシラン、ジエチルアミノプロピルトリメトキシシラン、ジプロピルアミノプロピルトリメトキシシラン、ジブチルアミノプロピルトリメトキシシラン、モノブチルアミノプロピルトリメトキシシラン、ジオクチルアミノプロピルトリメトキシシラン、ジブチルアミノプロピルメチルジメトキシシラン、ジブチルアミノプロピルジメチルモノメトキシシラン、ジメチルアミノフェニルトリエトキシシラン、トリメトキシシリル−γ−プロピルフェニルアミン、トリメトキシシリル−γ−プロピルベンジルアミン、トリメトキシシリル−γ−プロピルピペリジン、トリメトキシシリル−γ−プロピルモルホリン、トリメトキシシリル−γ−プロピルイミダゾール、γ−アミノプロピルジメチルメトキシシラン、γ−アミノプロピルメチルジメトキシシラン、４−アミノブチルジメチルメトキシシラン、４−アミノブチルメチルジエトキシシラン、Ｎ−（２−アミノエチル）アミノプロピルジメチルメトキシシランがあげられる。
【００５７】
窒素元素を含有する置換基を有するシラザン類の例としては、１，３−ビス（３−アミノプロピル）−１，１，３，３−テトラメチルジシラザン、１，３−ビス（４−アミノブチル）−１，１，３，３−テトラメチルジシラザン、１，３−ビス｛Ｎ（２−アミノエチル）アミノプロピル｝−１，１，３，３−テトラメチルジシラザン、１，３−ビス（ジメチルアミノプロピル）−１，１，３，３−テトラメチルジシラザン、１，３−ビス（ジエチルアミノプロピル）−１，１，３，３−テトラメチルジシラザン、１，３−ビス（３−プロピルアミノプロピル）−１，１，３，３−テトラメチルジシラザン、１，３−ビス（３−アミノプロピル）−１，１，３，３−テトラメチルジシラザンを挙げることができる。
【００５８】
窒素元素を含有する置換基を有するシロキサン類の例としては、１，３−ビス（３−アミノプロピル）−１，１，３，３−テトラメチルジシロキサン、１，３−ビス（４−アミノブチル）−１，１，３，３−テトラメチルジシロキサン、１，３−ビス｛Ｎ（２−アミノエチル）アミノプロピル｝−１，１，３，３−テトラメチルジシロキサン、１，３−ビス（ジメチルアミノプロピル）−１，１，３，３−テトラメチルジシロキサン、１，３−ビス（ジエチルアミノプロピル）−１，１，３，３−テトラメチルジシロキサン、１，３−ビス（３−プロピルアミノプロピル）−１，１，３，３−テトラメチルジシロキサン、１，３−ビス（３−アミノプロピル）−１，１，３，３−テトラメチルジシロキサンを挙げることができる。
【００５９】
窒素元素を含有する置換基を有するシリコーンオイルとしては、珪素原子上の置換基が水素，メチル基，フェニル基，一部または全部の水素がフッ素置換されたアルキル基のいずれかであるシリコーンオイルにおいて、窒素元素を有する置換基をポリシロキサン骨格の側鎖，両末端，片末端，側鎖片末端，側鎖両末端に導入した含窒素シリコーンオイルがあげられる。好ましくはこの置換基が次式で表わせる置換基であることが好ましい。
【００６０】
−Ｒ−ＮＲ₁₂Ｒ₁₃、−Ｒ’−ＮＲ₁₄−Ｒ”−ＮＲ₁₅Ｒ₁₆、
−Ｒ−Ｒ₁₇、−Ｒ−ＮＲ₁₄−Ｒ₁₇
式中、Ｒ，Ｒ’，Ｒ”はフェニレン基，アルキレン基を表わし、Ｒ₁₂，Ｒ₁₃，Ｒ₁₄，Ｒ₁₅，Ｒ₁₆は水素、置換基を有していても良いアルキル基，アリール基を表わし、Ｒ₁₇は含窒素複素環を表わす。またこれらの置換基がアンモニウム塩の形態をとっていても良い。
【００６１】
これらの含窒素シリコーンオイルは、エポキシ基、ポリエーテル基、メチルスチリル基、アルキル基、脂肪酸エステル基、アルコキシ基、カルボキシル基、カルビノール基、メタクリル基、メルカプト基、フェノール基、ビニル基の如き置換基を同時に有していても良い。
【００６２】
これらの含窒素シリコーンオイルは、２５℃における粘度が５，０００ｍｍ²／ｓ以下であることが好ましい。５，０００ｍｍ²／ｓを超える場合は、分散が不十分になり均一処理しづらくなる。さらに、分子量を１分子あたりのアミンの数で割ったアミン当量が２００〜４０，０００であることが好ましく、さらに好ましくは３００〜３０，０００であることが良い。このアミン当量が４０，０００を超える場合には、帯電の緩和効果が現われにくい場合があり、２００未満の場合には電荷のリークが増大し過ぎる場合がある。さらに、これらの含窒素シリコーンオイルを複数用いることも可能である。具体的にはアミノ変性シリコーンオイル、アミノ変性を含む異種官能基変性シリコーンオイルがあげられる。
【００６３】
無機微粉体Ｂ及びＣを表面処理するのに用いられるその他のシラン化合物としては、メトキシシラン，エトキシシラン，プロポキシシランの如きアルコキシシラン類、クロルシラン，ブロモシラン，ヨードシランの如きハロシラン類、ハイドロシラン類、アルキルシラン類、アリールシラン類、ビニルシラン類、アクリルシラン類、エポキシシラン類、シリル化合物類、シロキサン類、シリルウレア類、シリルアセトアミド類、及びこれらのシラン化合物類が有する異種の置換基を同時に有するシラン化合物類があげられる。その具体例として、トリメチルシラン、トリメチルクロルシラン、トリメチルエトキシシラン、ジメチルジクロルシラン、メチルトリクロルシラン、ｔ−ブチルジメチルメトキシシラン、アリルジメチルクロルシラン、アリルフェニルジクロルシラン、ベンジルメチルジクロルシラン、ブロムメチルジメチルクロルシラン、ｏ−クロルエチルトリクロルシラン、β−クロルエチルトリクロルシラン、クロルメチルジメチルクロルシラン、トリオルガノシリルメルカプタン、トリメチルシリルメルカプタン、トリオルガノシリルアクリレート、ビニルジメチルアセトキシシラン、ジメチルジエトキシシラン、ジメチルジメトキシシラン、ジフェニルジエトキシシラン、Ｎ，Ｏ−（ビストリメチルシリル）アセトアミド、Ｎ，Ｎ−ビス（トリメチルシリル）ウレア、ヘキサメチルジシロキサン、１，３−ジビニルテトラメチルジシロキサン、１，３−ジフェニルテトラメチルジシロキサン、１分子当たり２から１２個のシロキサン単位を有し末端に位置する単位にシラノール基を含有するジメチルポリシロキサンがあげられる。
【００６４】
無機微粉体Ｂ及びＣを表面処理するその他のシリコーンオイルとしては、例えばエポキシ変性，カルボキシル変性，カルビノール変性，メタクリル変性，メルカプト変性，フェノール変性，異種官能基変性の如き反応性シリコーン；ポリエーテル変性，メチルスチリル変性，アルキル変性，脂肪酸変性，アルコキシ変性，フッ素変性の如き非反応性シリコーン；ジメチルシリコーン，メチルフェニルシリコーン，ジフェニルシリコーン，メチルハイドロジェンシリコーンの如きストレートシリコーンがあげられる。
【００６５】
これらのシリコーンオイルの中でも非反応性シリコーン，ストレートシリコーンが好ましく用いられる。特に無機微粉体Ｃを処理するシリコーンオイルとして好ましい具体例としては、ジメチルシリコーン，メチルハイドロジェンシリコーンである。
【００６６】
これらのシリコーンオイルは、２５℃における粘度が５〜２，０００ｍｍ²／ｓであることが好ましい。更に好ましくは１０〜１，０００ｍｍ²／ｓである。５ｍｍ²／ｓ未満では目的の疎水性が得られないことがあり、２，０００ｍｍ²／ｓを超える場合には無機微粉体処理等に均一に処理しづらくなったり、凝集物ができやすく十分な流動性が得られないことがある。これらのシリコーンオイルを複数用いても良い。
【００６７】
特には無機微粉体Ｂ及びＣは、ＢＥＴ法による比表面積が２０ｍ²／ｇ以上であることが好ましく、更に好ましくは３０〜４００ｍ²／ｇであり、特に好ましくは５０〜３００ｍ²／ｇである。比表面積が２０ｍ²／ｇ未満であると、電荷のリーク，帯電の非局在化効果に劣るようになり、電荷の緩和均一化に効果を大きくは期待できなくなる場合がある。また比表面積が４００ｍ²／ｇを超える場合には、電荷のリークが大きすぎる場合が出てくる。
【００６８】
本発明の無機微粉体Ｂ及びＣの含有量はトナー粒子１００質量部に対し０．０５〜２．０質量部であることが好ましい。
【００６９】
本発明において無機微粉体Ｂ及びＣの処理母体１００質量部に対する、処理剤の処理量は１〜４０質量部であることが好ましく、さらに好ましくは２〜３０質量部である。１質量部未満では処理効果が現われず、４０質量部を超える場合には凝集物が増加し、流動性が低下することがある。
【００７０】
処理剤が窒素元素を有する置換基を有するシラン化合物の場合には、無機微粉体の処理母体１００質量部に対し０．０１〜２０質量部で処理されていることが好ましく、更に好ましくは０．０５〜１５質量部、特に好ましくは０．１〜１０質量部である。０．０１質量部未満では、電荷のリークによる過剰帯電の防止，正負両方の帯電の安定性が不十分となりやすい。２０質量部を超える場合には、電荷のリークが多くなり帯電不良や高湿下での帯電不足を発生したりすることがあり、負帯電性トナーの場合には逆極性粒子の発生、正帯電性トナーの場合には帯電過剰や選択現像を発生しやすくなる。
【００７１】
処理剤が窒素元素を有する置換基を有するシリコーンオイルの場合には、無機微粉体の処理母体１００質量部に対し０．１〜３０質量部で処理されていることが好ましく、更に好ましくは０．２〜２０質量部、特に好ましくは０．５〜１５質量部である。０．１質量部未満では電荷のリークによる過剰帯電の防止，正負両方の帯電の安定性が不十分となりやすい。３０質量部を超える場合には、電荷のリークが多くなり帯電不良や高湿下での帯電不足を発生したりすることがあり、負帯電性トナーの場合には逆極性に帯電した粒子が生じやすくなり、正帯電性トナーの場合には帯電過剰や選択現像を引き起こしやすくなる。
【００７２】
これら数種類の処理剤を用いる場合は、各処理剤が上記の範囲内で用いられ、全部あわせた処理量が、無機微粉体の処理母体１００質量部に対して５０質量部以下であることが好ましく、更に好ましくは３〜４５質量部、特に好ましくは６〜４０質量部である。処理量が５０質量部を超える場合には、凝集体を発生したり、処理が不均一になり易くなる。
【００７３】
本発明において、無機微粉体のｐＨ測定はガラス電極を用いたｐＨメータを用いて行なう。試料４．０ｇをビーカーに量り取リメタノール５０ｃｍ³を加え、試料をぬらし、更に純水５０ｃｍ³を加えてホモミキサーにて十分に撹拌する。その後ｐＨメータを用いてｐＨ値を測定する。
【００７４】
次に本発明に係るトナー粒子について説明する。
【００７５】
本発明のトナーに使用される結着樹脂としては、下記の重合体の使用が可能である。
【００７６】
例えば、ポリスチレン；ポリ−ｐ−クロルスチレン、ポリビニルトルエンの如きスチレン置換体の単重合体；スチレン−ｐ−クロルスチレン共重合体、スチレン−ビニルトルエン共重合体、スチレン−ビニルナフタリン共重合体、スチレン−アクリル酸エステル共重合体、スチレン−メタクリル酸エステル共重合体、スチレン−α−クロルメタクリル酸メチル共重合体、スチレン−アクリロニトリル共重合体、スチレン−ビニルメチルエ−テル共重合体、スチレン−ビニルエチルエーテル共重合体、スチレン−ビニルメチルケトン共重合体、スチレン−ブタジエン共重合体、スチレン−イソプレン共重合体、スチレン−アクリロニトリル−インデン共重合体の如きスチレン系共重合体；ポリ塩化ビニル、フェノール樹脂、天然変性フェノール樹脂、天然樹脂変性マレイン酸樹脂、アクリル樹脂、メタクリル樹脂、ポリ酢酸ビニール、シリコーン樹脂、ポリエステル樹脂、ポリウレタン、ポリアミド樹脂、フラン樹脂、エポキシ樹脂、キシレン樹脂、ポリビニルブチラール、テルペン樹脂、クマロンインデン樹脂、石油系樹脂が挙げられる。好ましい結着樹脂としては、スチレン系共重合体もしくはポリエステル樹脂がある。
【００７７】
スチレン系共重合体のスチレンモノマーに対するコモノマーとしては、例えばアクリル酸、アクリル酸メチル、アクリル酸エチル、アクリル酸ブチル、アクリル酸ドデシル、アクリル酸オクチル、アクリル酸−２−エチルヘキシル、アクリル酸フェニル、メタクリル酸、メタクリル酸メチル、メタクリル酸エチル、メタクリル酸ブチル、メタクリル酸オクチル、アクリロニトリル、メタクリルニトリル、アクリルアミドのような二重結合を有するモノカルボン酸もしくはその置換体；例えば、マレイン酸、マレイン酸ブチル、マレイン酸メチル、マレイン酸ジメチルのような二重結合を有するジカルボン酸およびその置換体；例えば塩化ビニル、酢酸ビニル、安息香酸ビニルのようなビニルエステル類；例えばエチレン、プロピレン、ブチレンのようなエチレン系オレフィン類；例えばビニルメチルケトン、ビニルヘキシルケトンのようなビニルケトン類；例えばビニルメチルエーテル、ビニルエチルエーテル、ビニルイソブチルエーテルのようなビニルエーテル類が挙げられる。これらのビニル単量体は、単独もしくは２つ以上用いられる。
【００７８】
スチレン系重合体またはスチレン系共重合体は架橋されていてもよく、また混合樹脂でもかまわない。
【００７９】
結着樹脂の架橋剤としては、主として２個以上の重合可能な二重結合を有する化合物を用いてもよい。例えば、ジビニルベンゼン、ジビニルナフタリンのような芳香族ジビニル化合物；例えば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ジメタクリレート、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ようなジビニル化合物；および３個以上のビニル基を有する化合物が挙げられる。これら架橋剤は単独もしくは混合物として用いられる。
【００８０】
該スチレン系共重合体の合成方法としては、塊状重合法，溶液重合法，懸濁重合法及び乳化重合法のいずれでも良い。
【００８１】
塊状重合法では、高温で重合させて停止反応速度を早めることで、低分子量の重合体を得ることもできるが、反応をコントロールしにくい問題点がある。溶液重合法では溶媒によるラジカルの連鎖移動の差を利用して、また開始剤量や反応温度を調節することで低分子量重合体を温和な条件で容易に得ることができ、ＧＰＣのクロマトグラムにおいて分子量５，０００〜１０万の領域に分子量の極大値を有する低分子量重合体を得る時には好ましい。
【００８２】
溶液重合で用いる溶媒としては、キシレン、トルエン、クメン、酢酸セロソルブ、イソプロピルアルコール、ベンゼンが用いられる。スチレンモノマー混合物の場合はキシレン、トルエン又はクメンが好ましい。重合生成するポリマーによって適宜選択される。
【００８３】
反応温度としては、使用する溶媒、開始剤、重合するポリマーによって異なるが、７０℃〜２３０℃で行なうのが良い。溶液重合においては溶媒１００質量部に対してモノマー３０〜４００質量部で行なうのが好ましい。
【００８４】
更に、重合終了時に溶液中で他の重合体を混合することも好ましく、数種の重合体をよく混合できる。
【００８５】
また、ＧＰＣのクロマトグラムにおいて分子量３０万〜５００万の領域に分子量の極大値を有する高分子量重合体や架橋重合体を得る重合法としては、乳化重合法や懸濁重合法が好ましい。
【００８６】
このうち、乳化重合法は、水にほとんど不溶の単量体（モノマー）を乳化剤で小さい粒子として水相中に分散させ、水溶性の重合開始剤を用いて重合を行なう方法である。この方法では反応熱の調節が容易であり、重合の行なわれる相（重合体と単量体からなる油相）と水相とが別であるから停止反応速度が小さく、その結果重合速度が大きく、高重合度のものが得られる。さらに、重合プロセスが比較的簡単であること、及び重合生成物が微細粒子であるために、トナーの製造において、着色剤及び荷電制御剤その他の添加物との混合が容易であること等の理由から、トナー用バインダー樹脂の製造方法として他の方法に比較して有利である。
【００８７】
しかし、添加した乳化剤のため生成重合体が不純になり易く、重合体を取り出すには塩析などの操作が必要であるので懸濁重合が簡便な方法である。
【００８８】
懸濁重合においては、水系媒体１００質量部に対して、モノマー１００質量部以下（好ましくは１０〜９０質量部）で行なうのが良い。使用可能な分散剤としては、ポリビニルアルコール、ポリビニルアルコール部分ケン化物、リン酸カルシウムが用いられ、水系媒体に対するモノマー量等で適当量があるが、一般に水系媒体１００質量部に対して０．０５〜１質量部で用いられる。重合温度は５０〜９５℃が適当であるが、使用する重合開始剤、目的とするポリマーによって適宜選択すべきである。また重合開始剤の種類としては、水に不溶或いは難溶のものであれば用いることが可能である。
【００８９】
これらの重合法において使用する重合開始剤としては、ｔ−ブチルパーオキシ−２−エチルヘキサノエート、クミンパーピバレート、ｔ−ブチルパーオキシラウレート、ベンゾイルパーオキサイド、ラウロイルパーオキサイド、オクタノイルパーオキサイド、ジ−ｔ−ブチルパーオキサイド、ｔ−ブチルクミルパーオキサイド、ジクミルパーオキサイド、２，２’−アゾビスイソブチロニトリル、２，２’−アゾビス（２−メチルブチロニトリル）、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（４−メトキシ−２，４−ジメチルバレロニトリル）、１，１−ビス（ｔ−ブチルパーオキシ）３，３，５−トリメチルシクロヘキサン、１，１−ビス（ｔ−ブチルパーオキシ）シクロヘキサン、１，４−ビス（ｔ−ブチルパーオキシカルボニル）シクロヘキサン、２，２−ビス（ｔ−ブチルパーオキシ）オクタン、ｎ−ブチル４，４−ビス（ｔ−ブチルパーオキシ）バリレート、２，２−ビス（ｔ−ブチルパーオキシ）ブタン、１，３−ビス（ｔ−ブチルパーオキシ−イソプロピル）ベンゼン、２，５−ジメチル−２，５−ジ（ｔ−ブチルパーオキシ）ヘキサン、２，５−ジメチル−２，５−ジ（ｔ−ブチルパーオキシ）ヘキサン、２，５−ジメチル−２，５−ジ（ベンゾイルパーオキシ）ヘキサン、ジ−ｔ−ブチルジパーオキシイソフタレート、２，２−ビス（４，４−ジ−ｔ−ブチルパーオキシシクロヘキシル）プロパン、ジ−ｔ−ブチルパーオキシα−メチルサクシネート、ジ−ｔ−ブチルパーオキシジメチルグルタレート、ジ−ｔ−ブチルパーオキシヘキサヒドロテレフタレート、ジ−ｔ−ブチルパーオキシアゼラート、２，５−ジメチル−２，５−ジ（ｔ−ブチルパーオキシ）ヘキサン、ジエチレングリコール−ビス（ｔ−ブチルパーオキシカーボネート）、ジ−ｔ−ブチルパーオキシトリメチルアジペート、トリス（ｔ−ブチルパーオキシ）トリアジン、ビニルトリス（ｔ−ブチルパーオキシ）シランが挙げられる。これらの重合開始剤は単独あるいは併用して使用できる。
【００９０】
その使用量はモノマー１００質量部に対し、０．０５質量部以上（好ましくは０．１〜１５質量部）の濃度で用いられる。
【００９１】
結着樹脂としてポリエステル樹脂を用いる場合、ポリエステル樹脂の組成は以下の通りである。
【００９２】
２価のアルコール成分としては、エチレングリコール、プロピレングリコール、１，３−ブタンジオール、１，４−ブタンジオール、２，３−ブタンジオール、ジエチレングリコール、トリエチレングリコール、１，５−ペンタンジオール、１，６−ヘキサンジオール、ネオペンチルグリコール、２−エチル−１，３−ヘキサンジオール、水素化ビスフェノールＡ、また式（Ａ）で表わされるビスフェノール及びその誘導体；
【００９３】
【外２】

（式中、Ｒはエチレンまたはプロピレン基を示し、ｘおよびｙはそれぞれ０以上の整数であり、かつ、ｘ＋ｙの平均値は０〜１０である。）
【００９４】
また式（Ｂ）で示されるジオール類；
【００９５】
【外３】

（式中、Ｒ’は−ＣＨ₂ＣＨ₂−又は
【００９６】
【外４】

を示し、ｘ’及びｙ’は０以上の整数であり、かつ、ｘ’＋ｙ’の平均値は０〜１０である。）が挙げられる。
【００９７】
２価の酸成分としては、例えばフタル酸、テレフタル酸、イソフタル酸、無水フタル酸の如きベンゼンジカルボン酸類又はその無水物、低級アルキルエステル；こはく酸、アジピン酸、セバシン酸、アゼライン酸の如きアルキルジカルボン酸類又はその無水物、低級アルキルエステル；ｎ−ドデセニルコハク酸、ｎ−ドデシルコハク酸の如きアルケニルコハク酸類もしくはアルキルコハク酸類、又はその無水物、低級アルキルエステル；フマル酸、マレイン酸、シトラコン酸、イタコン酸の如き不飽和ジカルボン酸類又はその無水物、低級アルキルエステルの如きジカルボン酸類及びその誘導体が挙げられる。
【００９８】
また、架橋成分としても働く３価以上のアルコール成分と３価以上の酸成分を併用することが好ましい。
【００９９】
３価以上の多価アルコール成分としては、例えばソルビトール、１，２，３，６−ヘキサンテトロール、１，４−ソルビタン、ペンタエリスリトール、ジペンタエリスリトール、トリペンタエリスリトール、１，２，４−ブタントリオール、１，２，５−ペンタントリオール、グリセロール、２−メチルプロパントリオール、２−メチル−１，２，４−ブタントリオール、トリメチロールエタン、トリメチロールプロパン、１，３，５−トリヒドロキシベンゼンが挙げられる。
【０１００】
また、３価以上の多価カルボン酸成分としては、例えばトリメリット酸、ピロメリット酸、１，２，４−ベンゼントリカルボン酸、１，２，５−ベンゼントリカルボン酸、２，５，７−ナフタレントリカルボン酸、１，２，４−ナフタレントリカルボン酸、１，２，４−ブタントリカルボン酸、１，２，５−ヘキサントリカルボン酸、１，３−ジカルボキシル−２−メチル−２−メチレンカルボキシプロパン、テトラ（メチレンカルボキシル）メタン、１，２，７，８−オクタンテトラカルボン酸、エンポール三量体酸、及びこれらの無水物、低級アルキルエステル；
次式
【０１０１】
【外５】

（式中、Ｘは炭素数１以上の側鎖を１個以上有する炭素数１〜３０のアルキレン基又はアルケニレン基を示す）
で表されるテトラカルボン酸、及びこれらの無水物、低級アルキルエステルの如き多価カルボン酸類及びその誘導体が挙げられる。
【０１０２】
アルコール成分として４０〜６０ｍｏｌ％、好ましくは４５〜５５ｍｏｌ％、酸成分として６０〜４０ｍｏｌ％、好ましくは５５〜４５ｍｏｌ％用いることが好ましい。
【０１０３】
また３価以上の多価の成分は、全成分中の１〜６０ｍｏｌ％であることも好ましい。
【０１０４】
本発明のトナー中には上記結着樹脂成分の他に、該結着樹脂成分の含有量より少ない割合でシリコーン樹脂、ポリウレタン、ポリアミド、エポキシ樹脂、ポリビニルブチラール、ロジン、変性ロジン、テルペン樹脂、フェノール樹脂、２種以上のα−オレフィンの共重合体樹脂成分を含有させることができる。
【０１０５】
また、本発明のトナーに用いられる結着樹脂のガラス転移点（Ｔｇ）は好ましくは４５〜８０℃、より好ましくは５０〜７０℃である。
【０１０６】
本発明においては、低温定着性や耐高温オフセット性の向上のためにワックスを含有させることが好ましい。
【０１０７】
本発明のトナーに含有されるワックスは、低分子量ポリエチレン、低分子量ポリプロピレン、オレフィンの共重合物、マイクロクリスタリンワックス、パラフィンワックス、サゾールワックスの如き脂肪族炭化水素系ワックス；酸化ポリエチレンワックスの如き脂肪族炭化水素系ワックスの酸化物または、それらのブロック共重合物；カルナバワックス、モンタン酸エステルワックスの如き脂肪酸エステルを主成分とするワックス類；脱酸カルナバワックスの如き脂肪酸エステル類を一部または全部を脱酸化したものが挙げられる。さらに、パルミチン酸、ステアリン酸、モンタン酸、あるいは更に長鎖のアルキル基を有する長鎖アルキルカルボン酸類の如き飽和直鎖脂肪酸類；ブランジン酸、エレオステアリン酸、バリナリン酸の如き不飽和脂肪酸類；ステアリンアルコール、アラルキルアルコール、ベヘニルアルコール、カルナウビルアルコール、セリルアルコール、メリシルアルコール、あるいは更に長鎖のアルキル基を有する長鎖アルキルアルコール類の如き飽和アルコール類；ソルビトールの如き多価アルコール類；リノール酸アミド、オレイン酸アミド、ラウリン酸アミドの如き脂肪酸アミド類；メチレンビスステアリン酸アミド、エチレンビスカプリン酸アミド、エチレンビスラウリン酸アミド、ヘキサメチレンビスステアリン酸アミドの如き飽和脂肪酸ビスアミド類、エチレンビスオレイン酸アミド、ヘキサメチレンビスオレイン酸アミド、Ｎ，Ｎ’−ジオレイルアジピン酸アミド、Ｎ，Ｎ’−ジオレイルセバシン酸アミドの如き不飽和脂肪酸アミド類；ｍ−キシレンビスステアリン酸アミド、Ｎ，Ｎ’−ジステアリルイソフタル酸アミドの如き芳香族系ビスアミド類；脂肪族炭化水素系ワックスにスチレンやアクリル酸の如きビニル系モノマーを用いてグラフト化させたワックス類；ベヘニン酸モノグリセリドの如き脂肪酸と多価アルコールの部分エステル化物；植物性油脂を水素添加することによって得られるヒドロキシ基を有するメチルエステル化合物が挙げられる。
【０１０８】
好ましく用いられるワックスとしては、アルキレンを高圧下でラジカル重合あるいは低圧下でチーグラー触媒又はその他の触媒を用いて重合した低分子量のアルキレンポリマー；高分子量のアルキレンポリマーを熱分解して得られるアルキレンポリマー；アルキレンポリマーを重合する際に副生する低分子量アルキレンポリマーを分離精製したもの；一酸化炭素及び水素からなる合成ガスからアーゲ法により得られる炭化水素の蒸留残分から、あるいは、これらを水素添加して得られる合成炭化水素から、特定の成分を抽出分別したワックスが挙げられる。これらワックスには酸化防止剤が添加されていてもよい。さらに、直鎖状のアルコール、脂肪酸、酸アミド、エステルあるいは、モンタン系誘導体で形成されるワックスが挙げられる。また、脂肪酸等の不純物を予め除去してあるものも好ましい。
【０１０９】
中でも好ましいものは、エチレンなどのオレフィンを重合したもの及びこの時の副生成物、フィッシャートロプシュワックスなどの炭素数が数千ぐらいまでの炭化水素を母体とするものが良い。また、炭素数が数百ぐらいまでの末端に水酸基をもつ長鎖アルキルアルコールも好ましい。更に、アルコールにアルキレンオキサイドを付加したものも好ましく用いられる。
【０１１０】
そして、これらのワックスから、プレス発汗法、溶剤法、真空蒸留、超臨界ガス抽出法、分別結晶化（例えば、融液晶析及び結晶ろ別）等を利用して、ワックスを分子量により分別し、分子量分布をシャープにしたワックスは、必要な融解挙動範囲の成分が占める割合が多くなるので更に好ましい。中でも、このように分別したワックスを２種類以上用いることが、低温定着性、耐ブロッキング性及び耐高温オフセット性に対し、これらの性能がバランス良く向上するために必要な融解挙動範囲のワックス成分を無駄なくトナー中に含有せしめられる点で特に好ましい。
【０１１１】
本発明のトナーには荷電制御剤を含有させることが好ましい。
【０１１２】
トナーを正荷電性に制御するものとして下記の物質がある。
【０１１３】
ニグロシン及び脂肪酸金属塩による変成物；トリブチルベンジルアンモニウム−１−ヒドロキシ−４−ナフトスルフォン酸塩、テトラブチルアンモニウムテトラフルオロボレートなどの四級アンモニウム塩、及びこれらの類似体であるホスホニウム塩の如きオニウム塩及びこれらのレーキ顔料、トリフェニルメタン染料及びこれらのレーキ顔料（レーキ化剤としては、りんタングステン酸、りんモリブデン酸、りんタングステンモリブデン酸、タンニン酸、ラウリン酸、没食子酸、フェリシアン化物、フェロシアン化物）高級脂肪酸の金属塩；ジブチルスズオキサイド、ジオクチルスズオキサイド、ジシクロヘキシルスズオキサイドの如きジオルガノスズオキサイド；ジブチルスズボレート、ジオクチルスズボレート、ジシクロヘキシルスズボレートの如きジオルガノスズボレート類；グアニジン化合物、イミダゾール化合物が挙げられる。これらを単独で或いは２種類以上組合せて用いることができる。これらの中でも、トリフェニルメタン化合物、イミダゾール化合物、カウンターイオンがハロゲンでない四級アンモニウム塩が好ましく用いられる。
【０１１４】
また一般式（１）
【０１１５】
【外６】

で表わされるモノマーの単重合体；上記モノマーと、前述したスチレン、アクリル酸エステル、メタクリル酸エステルの如き重合性モノマーとの共重合体を正荷電性制御剤として用いることもできる。この場合これらの荷電制御剤は、結着樹脂（の全部または一部）としての作用をも有する。
【０１１６】
特に下記一般式（２）で表わされるトリフェニルメタン化合物が本発明の構成においては好ましい。
【０１１７】
【外７】

【０１１８】
トナーを負荷電性に制御するものとして下記物質がある。
【０１１９】
例えば有機金属錯体、キレート化合物が有効であり、モノアゾ金属錯体、アセチルアセトン金属錯体、芳香族ハイドロキシカルボン酸、芳香族ダイカルボン酸系の金属化合物がある。他には、芳香族ハイドロキシカルボン酸、芳香族モノ及びポリカルボン酸及びその金属塩、無水物、エステル類；ビスフェノールの如きフェノール誘導体類がある。
【０１２０】
また次に示した一般式（３）で表わされるアゾ系金属錯体が好ましい。
【０１２１】
【外８】

【０１２２】
特に中心金属ＭとしてはＦｅ又はＣｒが好ましく、置換基としてはハロゲン、アルキル基、アニリド基が好ましい。
【０１２３】
あるいは次の一般式（４）に示した塩基性有機酸金属化合物も負帯電性制御剤として好ましい。
【０１２４】
【外９】

【０１２５】
特に中心金属としてはＦｅ，Ｃｒ，Ｓｉ，Ｚｎ又はＡｌが好ましく、置換基としては、好ましくはＣ₁〜Ｃ₁₈のアルキル基、アニリド基、アリール基、ハロゲン原子、特にはアルキル基又はハロゲン原子が好ましく、カチオンは水素イオン、アンモニウムイオン、脂肪族アンモニウムイオンが好ましい。
【０１２６】
電荷制御剤をトナーに含有させる方法としては、トナー内部に添加する方法と外添する方法がある。これらの電荷制御剤の使用量としては、結着樹脂の種類、他の添加剤の有無、分散方法を含めたトナー製造方法によって決定されるもので、一義的に限定されるものではないが、好ましくは結着樹脂１００質量部に対して０．１〜１０質量部、より好ましくは０．１〜５質量部の範囲で用いられる。
【０１２７】
また、一成分，二成分を問わず着色剤としては、カーボンブラック、アニリンブラック、アセチレンブラック、チタンホワイトやその他あらゆる顔料及び／又は染料を用いることができる。
【０１２８】
例えば本発明のトナーを磁性カラートナーとして使用する場合には、染料としては、Ｃ．Ｉ．ダイレクトレッド１、Ｃ．Ｉ．ダイレクトレッド４、Ｃ．Ｉ．アシッドレッド１、Ｃ．Ｉ．ベーシックレッド１、Ｃ．Ｉ．モーダントレッド３０、Ｃ．Ｉ．ダイレクトブルー１、Ｃ．Ｉ．ダイレクトブルー２、Ｃ．Ｉ．アシッドブルー９、Ｃ．Ｉ．アシッドブルー１５、Ｃ．Ｉ．ベーシックブルー３、Ｃ．Ｉ．ベーシックブルー５、Ｃ．Ｉ．モーダントブルー７、Ｃ．Ｉ．ダイレクトグリーン６、Ｃ．Ｉ．ベーシックグリーン４、Ｃ．Ｉ．ベーシックグリーン６を用いることができる。顔料としては、黄鉛、カドミウムイエロー、ミネラルファストイエロー、ネーブルイエロー、ナフトールイエローＳ、ハンザイエローＧ、パーマネントイエローＮＣＧ、タートラジンレーキ、赤口黄鉛、モリブデンオレンジ、パーマネントオレンジＧＴＲ、ピラゾロンオレンジ、ベンジジンオレンジＧ、カドミウムレッド、パーマネントレッド４Ｒ、ウオッチングレッドカルシウム塩、エオシンレーキ、ブリリアントカーミン３Ｂ、マンガン紫、ファストバイオレットＢ、メチルバイオレットレーキ、紺青、コバルトブルー、アルカリブルーレーキ、ビクトリアブルーレーキ、フタロシアニンブルー、ファーストスカイブルー、インダンスレンブルーＢＣ、クロムグリーン、酸化クロム、ピグメントグリーンＢ、マラカイトグリーンレーキ、ファイナルイエローグリーンＧを用いることができる。
【０１２９】
また、本発明のトナーを二成分フルカラー用トナーとして使用する場合には、次の様なものが挙げられる。
【０１３０】
マゼンタ用着色顔料としては、Ｃ．Ｉ．ピグメントレッド１，２，３，４，５，６，７，８，９，１０，１１，１２，１３，１４，１５，１６，１７，１８，１９，２１，２２，２３，３０，３１，３２，３７，３８，３９，４０，４１，４８，４９，５０，５１，５２，５３，５４，５５，５７，５８，６０，６３，６４，６８，８１，８３，８７，８８，８９，９０，１１２，１１４，１２２，１２３，１６３，２０２，２０６，２０７，２０９、Ｃ．Ｉ．ピグメントバイオレット１９、Ｃ．Ｉ．バットレッド１，２，１０，１３，１５，２３，２９，３５が挙げられる。
【０１３１】
かかるマゼンタ用着色顔料を単独で使用しても構わないが、マゼンタ用染料と併用してその鮮明度を向上させた方が、フルカラー画像の画質の点からより好ましい。かかるマゼンタ用染料としては、Ｃ．Ｉ．ソルベントレッド１，３，８，２３，２４，２５，２７，３０，４９，８１，８２，８３，８４，１００，１０９，１２１、Ｃ．Ｉ．ディスパースレッド９、Ｃ．Ｉ．ソルベントバイオレット８，１３，１４，２１，２７、Ｃ．Ｉ．ディスパースバイオレット１の如き油溶染料、Ｃ．Ｉ．ベーシックレッド１，２，９，１２，１３，１４，１５，１７，１８，２２，２３，２４，２７，２９，３２，３４，３５，３６，３７，３８，３９，４０、Ｃ．Ｉ．ベーシックバイオレット１，３，７，１０，１４，１５，２１，２５，２６，２７，２８の如き塩基性染料が挙げられる。
【０１３２】
その他の着色顔料として、シアン用着色顔料としては、Ｃ．Ｉ．ピグメントブルー２，３，１５，１６，１７、Ｃ．Ｉ．バットブルー６、Ｃ．Ｉ．アシッドブルー４５又は次式で示される構造を有するフタロシアニン骨格にフタルイミドメチル基を１〜５個置換した銅フタロシアニン顔料が挙げられる。
【０１３３】
【外１０】

【０１３４】
イエロー用着色顔料としては、Ｃ．Ｉ．ピグメントイエロー１，２，３，４，５，６，７，１０，１１，１２，１３，１４，１５，１６，１７，２３，６５，７３，８３、Ｃ．Ｉ．バットイエロー１，３，２０が挙げられる。
【０１３５】
これらの着色剤の使用量は、結着樹脂１００質量部に対して、０．１〜６０質量部であり、好ましくは０．１〜５０質量部、より好ましくは０．１〜２０質量部、特に好ましくは０．３〜１０質量部である。
【０１３６】
また、本発明のトナーにおいては、着色剤として磁性体を用い、磁性トナーとして使用することもできる。
【０１３７】
さらに本発明のトナーを磁性トナーとし、一成分系現像剤として使用する場合、磁性体としては、マグネタイト、ヘマタイト、フェライトの酸化鉄；鉄、コバルト、ニッケルのような金属或いはこれらの金属とアルミニウム、コバルト、銅、鉛、マグネシウム、スズ、亜鉛、アンチモン、ベリリウム、ビスマス、カドミウム、カルシウム、マンガン、セレン、チタン、タングステン、バナジウムのような金属との合金及びその混合物が挙げられる。
【０１３８】
これらの磁性体は、平均粒径が２μｍ以下、好ましくは０．１〜０．５μｍ程度のものが好ましい。トナー中に含有させる量としては、結着樹脂１００質量部に対し、好ましくは２０〜２００質量部、特に好ましくは４０〜１５０質量部が良い。
【０１３９】
さらにこれらの磁性体の飽和磁化としては、７．９６×１０²ｋＡ／ｍ（１０ｋＯｅ）の磁場で、５〜２００Ａｍ²／ｋｇ（ｅｍｕ／ｇ）、さらには１０〜１５０Ａｍ²／ｋｇ（ｅｍｕ／ｇ）であることが好ましい。
【０１４０】
磁性体の残留磁化としては、７．９６×１０²ｋＡ／ｍ（１０ｋＯｅ）の磁場で、１〜１００Ａｍ²／ｋｇ（ｅｍｕ／ｇ）、さらには１〜７０Ａｍ²／ｋｇ（ｅｍｕ／ｇ）であることが好ましい。
【０１４１】
磁性体の磁気特性は、「振動試料型磁力計ＶＳＭ−３Ｓ−１５」（東英工業（株）製）を用いて、外部磁場７．９６×１０²ｋＡ／ｍ（１０ｋＯｅ）の下で測定した値である。
【０１４２】
本発明のトナーは、二成分系現像剤として用いる場合には、キャリア粉と混合して用いられる。この場合には、トナーとキャリア粉との混合比はトナー濃度として０．１〜５０質量％、好ましくは０．５〜１０質量％、更に好ましくは３〜１０質量％が好ましい。本発明に使用しうるキャリアとしては、従来知られているものが全て使用可能であるが、具体的には、表面酸化又は未酸化の鉄、ニッケル、コバルト、マンガン、クロム、希土類の如き金属及びそれらの合金又は酸化物を用いることができ、平均粒径２０〜３００μｍの粒子が好ましく使用される。
【０１４３】
またそれらキャリア粒子の表面に、スチレン系樹脂、アクリル系樹脂、シリコーン系樹脂、フッ素系樹脂、ポリエステル系樹脂の如き樹脂を付着又は被覆させたものが好ましく使用される。
【０１４４】
本発明に係るトナー粒子を作製するためには、結着樹脂、磁性体、ワックス、荷電制御剤、その他の添加剤を、ヘンシェルミキサー、ボールミルの如き混合機により十分混合してから加熱ロール、ニーダー、エクストルーダーの如き熱混練機を用いて溶融混練して樹脂類を互いに相溶せしめた中に構成成分を分散又は溶解せしめ、冷却固化粉砕及び分級行って本発明に係るトナー粒子を得ることができる。
【０１４５】
得られたトナー粒子に対し、無機微粉体その他の添加剤をヘンシェルミキサーの如き混合機により十分混合し、本発明に係るトナーを得ることができる。
【０１４６】
本発明においては、トナーの重量平均粒径が、好ましくは４〜１３μｍ、より好ましくは５〜１２μｍであることが良い。トナーの重量平均粒径が４μｍ未満の場合には、十分な画像濃度が得られ難い。１３μｍを超える場合には、より高精細な画像形成が困難である。
【０１４７】
トナーの重量平均粒径の測定は、コールターカウンターＴＡ−ＩＩ型（コールター社製）を用いて行なうが、コールターマルチサイザー（コールター社製）を用いることも可能である。電解液は１級塩化ナトリウムを用いて１％ＮａＣｌ水溶液を調製する。たとえば、ＩＳＯＴＯＮ Ｒ−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フォン酸塩を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分間分散処理を行い、前記測定装置によりアパーチャーとして１００μｍアパーチャーを用いて、２．００μｍ以上のトナーの体積，個数を測定して体積分布と個数分布とを算出した。それから、本発明に係る体積分布から求めた重量基準の重量平均粒径（Ｄ₄）（各チャンネルの中央値をチャンネル毎の代表値とする）を求めた。
【０１４８】
チャンネルとしては、２．００〜２．５２μｍ未満；２．５２〜３．１７μｍ未満；３．１７〜４．００μｍ未満；４．００〜５．０４μｍ未満；５．０４〜６．３５μｍ未満；６．３５〜８．００μｍ未満；８．００〜１０．０８μｍ未満；１０．０８〜１２．７０μｍ未満；１２．７０〜１６．００μｍ未満；１６．００〜２０．２０μｍ未満；２０．２０〜２５．４０μｍ未満；２５．４０〜３２．００μｍ未満；３２．００〜４０．３０μｍ未満の１３チャンネルを用いた。
【０１４９】
本発明のトナーを用いて画像形成を行う場合、静電荷像保持体としては、導電体基体上に感光層としてａ−Ｓｉ層を有するａ−Ｓｉ感光体を使用するのが好ましい。
【０１５０】
ａ−Ｓｉ感光体の構成としては、感光層の下部に、下部電荷注入防止層を設け、基板からの電荷の進入を防ぐことができる。更に耐久性向上のため、感光層の上部に表面保護層を、静電荷像保持体の表面からの潜像電荷の注入を防ぐ上部電荷注入防止層を感光層の上部、あるいは表面保護層と感光層の間に設けることもできる。また、表面保護層と上部電荷注入防止層を兼ねた層を感光層の上部に設けてもよい。また、更に、長波長光の干渉現像の現出を防止するために長波長光遮断層を設けることもできる。
【０１５１】
これらの各層を設ける際には、各層を必要に応じてその特性を実用に適合させるため、水素原子やホウ素，アルミニウム，ガリウムの如き周期表第ＩＩＩ族の原子、ゲルマニウム，スズの如き周期表第ＩＶ族の原子、窒素，リン，ヒ素の如き周期表第Ｖ族の原子、酸素，イオウ，セレンの如き周期表第ＶＩ族の原子、フッ素，塩素，臭素等のハロゲン原子を単独または複合してａ−Ｓｉ形成時に導入して、各特性をコントロールすることができる。
【０１５２】
例えば、水素化ａ−Ｓｉ（ａ−Ｓｉ：Ｈ）にリン（Ｐ）をドープしたａ−Ｓｉ：Ｈ膜で構成された下部電荷注入防止層、ノンドープのａ−Ｓｉ：Ｈ膜で構成された感光層、そしてホウ素（Ｂ）をドープしたａ−Ｓｉ：膜で構成された上部電荷注入防止層をこの順序でドラム基体上に設けることにより、負電荷の静電荷像を保持する所望のアモルファスシリコン感光体ドラムを得ることができる。
【０１５３】
また、同様にホウ素をドープしたａ−Ｓｉ：Ｈ膜で構成された下部電荷注入防止層、ノンドープのａ−Ｓｉ：Ｈ膜で構成された感光層、そしてシリコンと炭素と水素から成るシリコン膜（即ちａ−ＳｉＣ：Ｈ膜）で構成された表面保護層をこの順序でドラム基体上に設けることにより、正電荷を保持する所望のアモルファスシリコン感光ドラムを得ることができる。
【０１５４】
このようなａ−Ｓｉ感光体により、可視光から半導体レーザー光まで分光感度をもつ静電荷像保持体とすることができ、該静電荷像保持体を用いることにより、半導体レーザー等からのレーザースポットでのデジタル潜像を該静電荷像保持体に形成することができる。
【０１５５】
次に、本発明の画像形成方法について説明する。
【０１５６】
次に、図１を参照しながら、本発明の画像形成方法を説明する。一次帯電器２で潜像担持体（感光体）１表面を負極性又は正極性に帯電し、アナログ露光又はレーザ光による露光５により静電荷像（例えば、イメージスキャニングによるデジタル潜像）を形成し、現像スリーブ４を具備する現像器１０のトナー１３で静電荷像を反転現像又は正規現像により現像する。現像部において、感光体１と現像スリーブ４との間には、バイアス印加手段１２により交互バイアス、パルスバイアス及び／又は交流バイアスが印加されている。トナー像は、中間転写体を介して、又は介さず（図１では、中間転写体を介さない場合を示す。）に搬送ローラー１４により搬送された転写材へ転写される。転写紙Ｐが搬送されて、転写部にくると転写帯電器３により転写紙Ｐの背面（感光体側と反対面）から正極性または負極性の帯電をすることにより、感光体表面上の負荷電性トナー像又は正荷電性トナー像が転写紙Ｐ上へ静電転写される。感光体１から分離された転写紙Ｐは、ヒータ１６を内包している加熱加圧ローラー定着器７により転写紙Ｐ上のトナー画像は、定着される。転写工程後の感光体１に残留するトナーは、クリーニングブレード８及びクリーニングローラー９を有するクリーニング手段で除去される。クリーニング後の感光体１は、イレース露光６により除電され、再度、一次帯電器２により帯電工程から始まる工程が繰り返される。
【０１５７】
次に現像装置について詳しく説明する。
【０１５８】
図２においては、現像装置Ｘ１は、公知のプロセスにより形成された静電潜像を保持する静電潜像保持体、例えば電子写真感光ドラム１は、矢印Ｂ方向に回転される。現像剤担持体としての現像スリーブ４は、現像容器としてのホッパー１７から供給されたトナー１３を担持して、矢印Ａ方法に回転することにより、現像スリーブ４と感光ドラム１とが対向した現像部Ｄにトナー１３を搬送する。現像スリーブ４内には、トナー１３を現像スリーブ４上に磁気的に吸引・保持するために、磁石１５が配置されている。トナー１３は現像スリーブ４との摩擦により、感光ドラム１上の静電潜像を現像可能な摩擦帯電電荷を得る。
【０１５９】
現像部Ｄに搬送されるトナー１３の層厚を規制するために、強磁性金属からなる現像剤層厚規制部材としての規制ブレード１１が、現像スリーブ４の表面から約２００〜３００μｍのギャップ幅を持って現像スリーブ４に臨むように、ホッパー１７から垂下されている。磁石１５の磁極Ｎ１からの磁力線が規制ブレード１１に集中することにより、現像スリーブ４上にトナー１３の薄層（現像剤層）が形成される。規制ブレード１１としては、磁性又は非磁性のどちらのものも使用することができる。
【０１６０】
現像スリーブ４上に形成されるトナー１３の薄層の厚みは、現像部Ｄにおける現像スリーブ４と感光ドラム１との間の最小間隙よりも薄いものであることが好ましい。このようなトナー薄層により静電潜像を現像する方式の現像装置、即ち非接触型現像装置に、本発明は特に有効である。しかし、現像部においてトナー層の厚みが現像スリーブ４と感光ドラム１との間の最小間隙以上の厚みである現像装置、即ち接触型現像装置にも、本発明は適用することができる。
【０１６１】
説明の煩雑を避けるため、以下の説明は、非接触型現像装置を例に関して行う。
【０１６２】
上記現像スリーブ４には、これに担持された現像剤であるトナー１３を飛翔させるために、バイアス印加手段１２により現像バイアス電圧が印加される。この現像バイアス電圧として直流電圧を使用するときは、静電潜像の画像部（トナー１３が付着して可視化される領域）の電位と背景部の電位との間の値の電圧が、現像スリーブ４に印加されることが好ましい。一方、現像画像の濃度を高め或は階調性を向上するために、現像スリーブ４に交番バイアス電圧を印加して、現像部Ｄに向きが交互に反転する振動電界を形成してもよい。この場合、上記画像部の電位と背景部の電位の間の値を有する直流電圧成分が重畳された交番バイアス電圧を現像スリーブ４に印加することが好ましい。
【０１６３】
高電位部と低電位部を有する静電潜像の高電位部にトナーを付着させて可視化する、いわゆる正規現像では、静電潜像の極性と逆極性に帯電するトナーを使用し、一方、静電潜像の低電位部にトナーを付着させて可視化する、いわゆる反転現像では、トナーは静電潜像の極性と同極性に帯電するトナーを使用する。尚、高電位と低電位というのは、絶対値による表現である。いずれにしても、トナー１３は現像スリーブ４との摩擦により静電潜像を現像するための極性に帯電する。
【０１６４】
図３は現像装置の他の実施形態を示す構成図である。
【０１６５】
図３の現像装置Ｘ２では、現像スリーブ４上のトナー１３の層厚を規制するための現像剤層厚規制部材として、ウレタンゴム及びシリコーンゴムの如きゴム弾性を有する材料、或はリン青銅及びステンレス鋼の如き金属弾性を有する材料の弾性板１８を使用し、この弾性板１８を現像スリーブ４に圧接させていることが特徴である。このような現像装置では、現像スリーブ４上に更に薄いトナー層を形成することができる。図３の現像装置Ｘ２のその他の構成は、図２に示した現像装置Ｘ１と基本的に同じで、図３において図２に付した符号と同一の符号は同一の部材を示す。
【０１６６】
上記のようにして現像スリーブ４上にトナー層を形成する図３に示すような現像装置Ｘ２は、弾性板１８によりトナーを現像スリーブ４上に擦りつけるため、トナーの摩擦帯電量も多くなり、画像濃度の向上が図られる。特に非磁性一成分系現像剤においては、このような弾性板を用いた現像装置が用いられることが好ましい。
【０１６７】
【実施例】
以下、本発明を実施例により具体的に説明するが、これは、本発明をなんら限定するものではない。
【０１６８】
（無機微粉体Ａの製造例１〜７及び比較製造例１〜２）
バストネサイト精鉱を粉砕し、硫酸にて溶解し、その後、溶媒抽出により各希土類元素量を調整した後、希土類元素の炭酸塩とした後、焼成し、酸化希土化合物とする。放冷後、湿式粉砕を行いながら、表１に示すとおりのフッ素含有量になるようにフッ酸を添加し、乾燥後、電気炉で、６００〜１０００℃で５〜１０時間焼成し、粉砕・分級工程をへて表１に示す通りの製造例１〜７の無機微粉体Ａ−１〜Ａ−７及び比較製造例１〜２の無機微粉体ａ−１，ａ−２を得た。
【０１６９】
（無機微粉体の比較製造例３）
バストネサイト精鉱を選鉱し、粉砕、乾燥し、電気炉で、６００〜１０００℃で５〜１０時間焼成後、粉砕・分級工程をへて、比較製造例３の無機微粉体ａ−３を得た。得られた無機微粉体ａ−３の組成を表１に示す。
【０１７０】
（無機微粉体の比較製造例４）
モナザイト精鉱から得られた塩化希土からアルカリ分解処理して、希土類元素の水酸化物した後、酸処理して乾燥させ、焼成し、粉砕・分級工程をへて表１に示す通りの比較製造例４の無機微粉体ａ−４を得た。
【０１７１】
（無機微粉体Ｂ及びＣの製造）
容器中にトルエン１０００質量部とシリカ２００質量部を入れ、ミキサーにより撹拌してスラリーとし、γ−アミノプロピルトリエトキシシラン６質量部、ジメチルシリコーンオイル（５０ｍｍ²／ｓ）３４質量部を添加し、更にミキサーで撹拌した。このスラリーを、ジルコニアボールをメディアとしてサンドミルに３０分間かけた。スラリーをサンドミルから取り出し、６０℃で減圧しながらトルエンを除去した後、ステンレス容器で撹拌しながら２５０℃で２時間乾燥した。さらにハンマーミルにて解砕処理をし、無機微粉体ｉを得た。同様にして、母体及び処理剤を表２に示すとおりにする以外は無機微粉体ｉと同様にして無機微粉体ｉｉ及びｉｉｉを得た。
【０１７２】
密閉型高速撹拌ミキサーにシリカ２００質量部を入れ、窒素置換した。撹拌しながらヘキサメチルジシラザン４０質量部を噴霧し、添加終了後室温で１０分間撹拌した後、高速撹拌しながら３００℃に昇温させて１時間撹拌した。撹拌しながら室温に戻し、ミキサーから粉体を取り出し、無機微粉体ｉｖを得た。
【０１７３】
得られた無機微粉体ｉ〜ｉｖの物性を表２に示す。
【０１７４】
＜実施例１＞
・スチレン−ブチルアクリレート共重合体（結着樹脂） １００質量部
・磁性酸化鉄（磁性体） ９０質量部
・トリフェニルメタン系レーキ顔料（正荷電性制御剤） ２質量部
・低分子量ポリエチレン（離型剤） ４質量部
上記材料をヘンシェルミキサーで前混合した後、１３０℃に設定した二軸混練押し出し機によって、溶融混練した。得られた混練物を冷却し、カンターミルで粗粉砕した後、ジェット気流を用いた微粉砕機で粉砕し、得られた微粉砕粉末をコアンダ効果を利用した多分割分級機を用いて分級し、トナー粒子を得た。トナー粒子１００質量部に対し、無機微粉体Ａ−１を３．０質量部、無機微粉体ｉを１．０質量部、外添混合して正帯電性トナーを得た。得られた正帯電性トナーは、重量平均粒径が７．２μｍであった。
【０１７５】
このトナーを用いて、アモルファスシリコンドラムを有する市販の電子写真複写機ＮＰ６０８５（キヤノン株式会社製）改造機により、複写試験を行った。変更点としては、正帯電性トナーを使用した反転現像が可能となるようにバイアス、その他（非画像部ドラム電位４００Ｖ，画像部ドラム電位５０Ｖ，現像バイアスＤＣ分２８０Ｖ，画像電位コントラスト２３０Ｖ、ドラム表面温度４２℃設定）を改造し、更にクリーニング方式としては、磁束密度１０００ガウスの極を８つ持つマグネットローラーであるクリーニングローラーと、ポリウレタンゴムからなるクリーニングブレード（硬度７０度、厚さ３ｍｍ）とを設置した。このとき、マグネットローラーは対感光ドラム周速８０％で順方向に回転し、感光ドラムとマグネットローラーのギャップは１．２ｍｍとし、クリーニングブレードの感光ドラムヘの侵入量を０．５ｍｍとした。
【０１７６】
複写試験は、温度２３℃，湿度５％ＲＨ（常温低湿）の環境下、及び、温度３０℃，湿度８０％ＲＨ（高温高湿）の環境下で、それぞれ１００，０００枚の画出しを行い、以下の項目について評価した。また結果を表３及び表４に示す。
【０１７７】
１）画像濃度
マクベス濃度計（マクベス社製）でＳＰＩフィルターを使用して、反射濃度測定を行い、直径５ｍｍ丸の画像を測定した。
【０１７８】
２）カブリ
反射濃度計（リフレクトメーターモデルＴＣ６ＤＳ東京電色社製）を用いて行い、画像形成後の白地部反射濃度最悪値をＤｓ、画像形成前の転写材の反射平均濃度をＤｒとし、Ｄｓ−Ｄｒをカブリ量としてカブリの評価を行った。数値の少ない方がカブリ抑制が良い。
【０１７９】
３）感光体ドラム表面のトナー固着
常温低湿環境下（温度２３℃，湿度５％ＲＨ）及び高温高湿環境下（温度３０℃，湿度８０％ＲＨ）での１００，０００枚耐久終了後の感光体表面及び複写画像を目視により評価した。
Ａ：未発生
Ｂ：わずかに発生するが、画像への影響はない。
Ｃ：固着があるが画像への影響は少ない。
Ｄ：固着が多く画像への影響が大きい。
【０１８０】
４）画像流れ
常温低湿環境下（温度２３℃，湿度５％ＲＨ）及び高温高湿環境下（温度３０℃，湿度８０％ＲＨ）での、１００，０００枚目の画像を用いて、画像流れの評価を行った。
Ａ：未発生
Ｂ：ごくわずかに発生する。
Ｃ：わずかに発生する。
Ｄ：発生し、画像のにじむ部分が広い。
【０１８１】
５）クリーニングすり抜け
常温低湿環境下（温度２３℃，湿度５％ＲＨ）及び高温高湿環境下（温度３０℃，湿度８０％ＲＨ）での、１００，０００枚耐久終了後のクリーニングブレード及び複写画像を目視により評価した。
Ａ：未発生
Ｂ：クリーニングブレードに凝集物が溜まっているが、すり抜けの発生はない。
Ｃ：クリーニングブレードのトナーすり抜けが発生しており、画像にスジが発生している。
【０１８２】
６）クリーニングブレード端部からのトナーもれ
常温低湿環境下（温度２３℃，湿度５％ＲＨ）及び高温高湿環境下（温度３０℃，湿度８０％ＲＨ）での、１００，０００枚耐久終了後のクリーニングブレード及び感光体表面を目視により評価を行った。
Ａ：もれ未発生
Ｂ：ブレード端部よりトナーがごくわずかに漏れる。
Ｃ：ブレード端部よりトナーが漏れるが、ドラム端部融着の発生はない。
Ｄ：ドラム端部へのトナー融着が発生している。
【０１８３】
７）ドラム削れ量
１００，０００枚耐久前後のドラムの膜厚を測定し、その差を削れ量とした。
【０１８４】
表には、１００，０００枚あたりの削れ量をｎｍ単位で表示した。後述の実施例６では１５，０００枚耐久時で測定し、表にはμｍ単位で表示した。
【０１８５】
＜実施例２＞
無機微粉体Ａ−１の代わりに、無機微粉体Ａ−２を２．０質量部使用する以外は、実施例１と同様にして正帯電性トナーを製造、評価した。結果を表３及び表４に示す。
【０１８６】
＜実施例３＞
無機微粉体Ａ−１の代わりに、無機微粉体Ａ−３を１．０質量部使用する以外は、実施例１と同様にして正帯電性トナーを製造、評価した。結果を表３及び表４に示す。
【０１８７】
＜実施例４＞
無機微粉体Ａ−１および無機微粉体ｉの代わりに、無機微粉体Ａ−４を４．０質量部および無機微粉体ｉｉを０．８質量部使用する以外は、実施例１と同様にして正帯電性トナーを製造、評価した。結果を表３及び表４に示す。
【０１８８】
＜実施例５＞
無機微粉体Ａ−１および無機微粉体ｉの代わりに、無機微粉体Ａ−５を３．０質量部および無機微粉体ｉｉを０．８質量部使用する以外は、実施例１と同様にして正帯電性トナーを製造、評価した。結果を表３及び表４に示す。
【０１８９】
＜実施例６＞
・スチレン−ブチルアクリレート共重合体（樹脂） １００質量部
・磁性酸化鉄（磁性体） ９０質量部
・モノアゾ染料系クロム錯体（負荷電性制御剤） ２質量部
・低分子量ポリプロピレン（離型剤） ４質量部
上記材料をヘンシェルミキサーで前混合した後、１３０℃に設定した二軸混練押し出し機によって、溶融混練した。得られた混練物を冷却し、カンターミルで粗粉砕した後、ジェット気流を用いた微粉砕機で粉砕し、得られた微粉砕粉末をコアンダ効果を利用した多分割分級機を用いて分級し、トナー粒子を得た。トナー粒子１００質量部に対し、無機微粉体Ａ−６を０．５質量部、無機微粉体ｉｉｉを１．０質量部、外添混合して負帯電性トナーを得た。得られた負帯電性トナーは、重量平均粒径が６．５μｍであった。
【０１９０】
上記トナーをレーザービームプリンターＬＢＰ−９３０（キヤノン株式会社製、ＯＰＣ感光ドラムを使用）を、非画像部ドラム電位が−７００Ｖ、画像部ドラム電位が−１７０Ｖ、現像バイアスＤＣ分が−５００Ｖ、画像電位コントラスト３３０Ｖとなるように設定し、クリーナー部材として、ポリウレタンゴムからなるクリーニングブレード（硬度６５度、厚さ１．２ｍｍ、感光体への侵入量０．９ｍｍ）を設置した。以上の条件で１５，０００枚のプリントを行い実施例１と同様の方法で評価を行った。結果を表３及び表４に示す。
【０１９１】
＜実施例７＞
・架橋ポリエステル樹脂（結着樹脂） １００質量部
・磁性酸化鉄（磁性体） ９０質量部
・モノアゾ染料系クロム錯体（負荷電性制御剤） ２質量部
・低分子量ポリプロピレン（離型剤） ４質量部
上記材料をヘンシェルミキサーで前混合した後、１３０℃に設定した二軸混練押し出し機によって、溶融混練した。得られた混練物を冷却し、カンターミルで粗粉砕した後、ジェット気流を用いた微粉砕機で粉砕し、得られた微粉砕粉末をコアンダ効果を利用した多分割分級機を用いて分級し、トナー粒子を得た。トナー粒子１００質量部に対し、無機微粉体Ａ−７を５．０質量部、無機微粉体ｉｖを１．０質量部、外添混合して負帯電性トナーを得た。得られた負帯電性トナーは、重量平均粒径が７．８μｍであった。
【０１９２】
上記トナーを、市販のアモルファスシリコンドラムを有する電子写真複写機ＮＰ６０８５（キヤノン株式会社製）を非画像部ドラム電位５０Ｖ，画像部ドラム電位４２０Ｖ，現像バイアスＤＣ分１９０Ｖ，画像電位コントラスト２３０Ｖ，ドラム表面温度４２℃設定となるように設定し、更にクリーニング方式としては、クリーニングローラーとして磁束密度７５０ガウスの極を６つ持つのマグネットローラーとポリウレタンゴムからなるクリーニングブレード（硬度７３度、厚さ３ｍｍ）を設置した。このとき、マグネットローラーは対感光ドラム周速８０％で順方向に回転し、感光ドラムとマグネットローラーのギャップは１．２ｍｍであり、クリーニングブレードの感光ドラムヘの侵入量を０．５ｍｍと設定した。これを用い、実施例１と同様にして評価した。結果を表３及び表４に示す。
【０１９３】
＜比較例１＞
無機微粉体Ａ−１の代わりに、無機微粉体ａ−１を使用する以外は、実施例１と同様にして正帯電性トナーを製造、評価した。結果を表３及び表４に示す。
【０１９４】
＜比較例２＞
無機微粉体Ａ−７の代わりに、無機微粉体ａ−２を使用する以外は、実施例７と同様にして負帯電性トナーを製造、評価した。結果を表３及び表４に示す。
【０１９５】
＜比較例３，４＞
無機微粉体Ａ−１の代わりに、無機微粉体ａ−３，ａ−４を使用する以外は、実施例１と同様にして正帯電性トナーを製造、評価した。結果を表３及び表４に示す。
【０１９６】
＜実施例８＞
・スチレン−ブチルアクリレート共重合体（結着樹脂） １００質量部
・銅フタロシアニン（着色剤） ３．５質量部
・トリフェニルメタン系レーキ顔料（正荷電性制御剤） ２質量部
・低分子量ポリエチレン（離形剤） ３質量部
上記材料をヘンシェルミキサーで前混合した後、１２０℃に設定した２軸混練押し出し機によって溶融混練した。得られた混練物を冷却し、カッターミルで粗粉砕した後、ジェット気流を用いた微粉砕機を用いて微粉砕し、得られた微粉砕物を更に風力分級機で分級し、トナー粒子を得た。トナー粒子１００質量部に対し、無機微粉体Ａ−１を１．０質量部、無機微粉体ｉを１．０質量部、外添混合して正帯電性非磁性トナーを得た。得られたトナーは、重量平均粒径が８．５μｍであった。
【０１９７】
このトナーを、市販の複写機ＦＣ−３３０（キヤノン（株）社製 ＯＰＣ感光ドラム使用）を用い、非画像部ドラム電位−１５０Ｖ、画像部ドラム電位−６００Ｖ、現像バイアスＤＣ分−２８０Ｖ、画像電位コントラスト３２０Ｖと設定し、クリーニング部材として、ポリウレタンゴムからなるクリーニングブレード（硬度６５度、厚さ１．２ｍｍ、感光体への侵入量０．７ｍｍ）を設置した。以上の条件で温度２３℃、湿度５％ＲＨ（常温低湿）の環境に引き続き、温度３０℃、湿度８０％ＲＨ（高温高湿）の環境で１０００枚の複写試験を行い、実施例１と同様にして、各種評価（ドラム削れの評価を除く）を行った。結果を表３及び表４に示す。
【０１９８】
【表１】

【０１９９】
【表２】

【０２００】
【表３】

【０２０１】
【表４】

【０２０２】
【発明の効果】
本発明のトナー及び画像形成方法によれば、画像流れ、トナー融着、クリーニング不良等が発生せず、アモルファスシリコン感光体を用いた電子写真装置においても優れた現像性や耐久性が得られ、また正帯電トナーとして用いても安定した帯電特性を得ることができる。
【図面の簡単な説明】
【図１】本発明の画像形成方法を実施するための画像形成装置の一具体例を示す概略的説明図である。
【図２】現像装置の拡大説明図である。
【図３】現像装置の他の一具体例を示す概略的説明図である。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to toner for use in electrophotography, toner jet, and an image forming method using the toner.
[0002]
[Prior art]
Many electrophotographic methods are known as described in US Pat. No. 2,297,691, Japanese Patent Publication No. 42-23910 and Japanese Patent Publication No. 43-24748. In general, a photoconductive substance is used to form an electrostatic latent image on a photoreceptor by various means, and then the latent image is developed with toner, and a recording material such as paper (transfer material) as necessary. After the toner image is transferred to the toner image, the toner image is fixed by heating, pressure, heating pressure or solvent vapor to obtain a toner image. Conventionally, an analog method in which an original image is exposed and the reflected light is exposed to a photosensitive member to obtain a latent image has been generally performed. However, in recent years, the original reflected light is converted into an electric signal, and the signal is converted into an electric signal. After processing, electrophotographic and electrostatic recording systems using a digital method in which a latent image is formed by directly irradiating a photosensitive member with laser light, LED light, or the like based on the processing have been commercialized.
[0003]
In many electrophotographic systems using digital image signals, a light emitter (such as a semiconductor laser) is turned on and off (ON-OFF) in accordance with the image signal, and the light is projected onto a photoconductor. In this case, the printing rate (the ratio of the printing area per page) is usually 30% or less, and the so-called reversal development in which the character portion is exposed is advantageous in terms of the life of the light emitter. Therefore, the latent image is formed by gathering constant potential dots (pixel units), and the solid portion, the halftone portion, and the light portion are expressed by changing the dot density. However, in such a digital method, compared to the analog method, a phenomenon called “image flow” in which a latent image charge flow occurs due to adhesion of low-resistance contaminants to the drum, particularly in a halftone portion, and the image blurs. In this case, there is a problem that the developed image tends to appear due to the property of image formation.
[0004]
When a digital inverted latent image is formed using a semiconductor laser or the like, a photosensitive drum having spectral sensitivity in the infrared region near 800 nm is used.
[0005]
As a photoconductor having spectral sensitivity in this region, there is an amorphous silicon (hereinafter referred to as a-Si) photoconductor. Since the a-Si photoreceptor has good durability such as heat resistance and friction resistance, has a wide sensitivity region and high sensitivity, various laser beams can be used. Functionalization can be achieved. However, although the a-Si photoreceptor has such advantages, it is generally difficult to increase the film thickness from the viewpoint of cost and mass productivity, and the chargeability cannot be increased with a practical level a-Si photoreceptor. For this reason, it is necessary to use a toner that can be developed with a low potential contrast, and it is important to increase the charge amount of the toner and to control it as uniformly as possible. In particular, it is important to prevent a decrease in toner charge amount and toner fluidity in a high temperature and high humidity environment.
[0006]
Moreover, although the a-Si photosensitive member has high surface hardness and high durability, there is a problem that the surface of the photosensitive member is difficult to be scraped. The toner developed on the photoconductor in the electrophotographic process is transferred to a transfer material such as paper, but residual toner remaining on the photoconductor without being transferred at that time is removed by a cleaning member. It is difficult to completely remove the residual toner, and the residual toner that has not been removed is usually scraped together with the surface of the photoreceptor due to friction with the toner in the subsequent development and transfer processes. Don't be. However, since the a-Si photosensitive member has a high hardness, the surface is difficult to be scraped, and it is difficult to remove the residual toner, thereby easily causing toner fusion to the photosensitive member.
[0007]
Further, impurities such as paper dust generated during the electrophotographic process, ozone deposits, or exudates from the conveyance rubber roller attached to the photoreceptor via the transfer material are present on the surface of the photoreceptor. Normally, these impurities are not scraped together with the surface of the photoconductor as in the case of the residual toner. However, in the case of the a-Si photoconductor, it is difficult to remove the impurities as in the case of the residual toner, and image defects such as image flow are likely to occur. .
[0008]
In order to prevent image flow, a method has been proposed in which a drum heater for temperature control is built in the photoconductor, and the surface temperature of the photoconductor is increased to lower the relative humidity, thereby suppressing moisture adhesion to the surface of the photoconductor. ing. However, it is not possible to raise the surface temperature of the photoreceptor so much in consideration of the effect of temperature rise in the apparatus and reduction of power consumption. Therefore, improvement from the toner side is desired.
[0009]
As the cleaning member, a cleaning blade or a cleaning roller is known, and these can be used alone or in combination. The cleaning blade method is a method in which a blade having elasticity is brought into contact with the photoreceptor to physically scrape the residue on the photoreceptor. Usually, toner is present at a portion where the blade and the photosensitive member are in contact with each other, and good cleaning is always performed with the role of lubrication between the cleaning blade and the photosensitive member by the somewhat existing toner. However, when the toner is rapidly reduced, the lubricity is partially deteriorated, and the cleaning blade is turned in the rotating direction of the photosensitive member or vibrated on the photosensitive member, so that the residual toner on the photosensitive member cannot be removed. It becomes a state. Therefore, for the purpose of supplying stable toner to the cleaning blade, a cleaning roller is installed on the upstream side of the cleaning blade in the rotation direction of the photosensitive member, and the residue on the photosensitive member is scraped and applied to the photosensitive member by rubbing. Has been implemented. However, in this case, agglomerates such as toner or paper dust are easily generated in the cleaner including the cleaning roller, and the agglomerates are caught in the gap between the cleaner blade and the photosensitive member, and the toner slips from there. It becomes easy to do.
[0010]
For the purpose of these improvements, various proposals have been made to include fine inorganic powder as an abrasive or lubricant in the toner. For example, the conductive oxidation described in JP-A-58-66951, JP-A-59-168458, JP-A-59-168458, JP-A-59-168460 and JP-A-59-170847. The inclusion of zinc and tin oxide is disclosed. However, with such a method, it is difficult to obtain a stable image density in digital high-speed development or low-potential development. Further, many proposals have been made to use cerium oxide particles as abrasive particles. For example, JP-A-62-1119550 discloses that negatively charged toner contains cerium oxide together with hydrophobic silica. However, in this case as well, stable charging cannot be obtained in the positively charged toner, or in the digital high-speed development and digital reversal development. Further, Japanese Patent Application Laid-Open No. 61-236560 discloses a method of adding a rare earth element compound containing cerium oxide as a main component. However, the hardness of these mixtures is not constant and the photoreceptor is shaved unevenly. As a result, the coefficient of friction between the photosensitive member and the cleaning blade differs between the polished part and the unpolished part, and there is a problem that the blade is turned over and slipped out. Furthermore, in JP-A-1-204068 and JP-A-8-82949, it is disclosed that cerium fluoride or fluorine-containing cerium oxide particles are contained, and a preferable effect is obtained. Difficult to keep constant. Further, when these cerium oxide particles are used, the charge balance of the toner is lost, and problems such as density stability and fogging may occur. That is, at present, there is nothing that has a good balance of abrasiveness, lubricity, cleaning properties and developability.
[0011]
[Problems to be solved by the invention]
The object of the present invention is to solve the above-mentioned problems.
[0012]
That is, an object of the present invention is to provide a toner having excellent developability, a stable image density even under various environments such as high temperature and high humidity, low temperature and low humidity, and low fog.
[0013]
It is a further object of the present invention to provide a toner that is free from toner fusion and that does not cause image drift.
[0014]
A further object of the present invention is to provide an image forming method which can obtain good developability even when an amorphous silicon photoreceptor is used.
[0015]
A further object of the present invention is to provide an image forming method in which image flow does not occur even if the drum surface temperature is not increased so much by a drum heater.
[0016]
Furthermore, an object of the present invention is to provide an image forming method in which cleaning failure such as blade slipping, blade turning, and toner leakage from the blade end portion does not occur in a cleaning process using a cleaning blade or a cleaning roller in combination. There is.
[0017]
It is a further object of the present invention to provide an image forming method in which no contaminants adhere to the photosensitive member and no image flow occurs even when a conveying rubber roller is used as a transfer material conveying member.
[0018]
[Means for Solving the Problems]
The present invention is a toner having toner particles containing at least a binder resin and a colorant, and inorganic fine powder A,
The inorganic fine powder A contains 88.0 to 97.0% by mass of a rare earth element compound containing a rare earth element oxide,
In the rare earth element compound, Ce is converted into an oxide (CeO₂40.0 to 65.0% by mass in terms of conversion), and La is converted to oxide (La₂O_Three25.0-45.0% by mass in terms of conversion), and Nd is converted to oxide (Nd₂O_Three1.0 to 10.0% by mass in terms of conversion), and Pr is converted to oxide (Pr₆O₁₁1.0 to 10.0% by mass in terms of conversion)
The rare earth element compound includes a rare earth element fluoride compound, and the inorganic fine powder A has a fluorine element content of 2.0 to 11.0% by mass.
[0019]
Further, the present invention provides a charging step for charging the latent image carrier, an image forming step for forming an electrostatic image on the charged latent image carrier, and developing the electrostatic image with toner to form a toner image. A development step, a transfer step of transferring the toner image formed on the latent image carrier onto the recording material via or without the intermediate transfer member, and a fixing step of heating and fixing the toner image on the recording material. An image forming method having at least a cleaning step of cleaning the surface of the latent image carrier after transfer with a cleaning member,
The toner has toner particles containing at least a binder resin and a colorant, and inorganic fine powder A,
The inorganic fine powder A contains 88.0 to 97.0% by mass of a rare earth element compound containing a rare earth element oxide,
In the rare earth element compound, Ce is converted into an oxide (CeO₂40.0 to 65.0% by mass in terms of conversion), and La is converted to oxide (La₂O_Three25.0-45.0% by mass in terms of conversion), and Nd is converted to oxide (Nd₂O_Three1.0 to 10.0% by mass in terms of conversion), and Pr is converted to oxide (Pr₆O₁₁1.0 to 10.0% by mass in terms of conversion)
The rare earth element compound includes a rare earth element fluoride compound, and the inorganic fine powder A has a fluorine element content of 2.0 to 11.0% by mass.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
The toner of the present invention is a toner having toner particles containing at least a binder resin and a colorant and inorganic fine powder A, wherein the inorganic fine powder A contains a rare earth element compound containing a rare earth element oxide. 0-97.0% by mass (preferably 89.0-96.0% by mass, more preferably 90.0-95.0% by mass), effectively preventing fusion and image flow can do. When the content of the rare earth compound in the inorganic fine powder A is less than 88.0% by mass, unevenness is likely to occur in the polishing effect, and when the rare earth element compound exceeds 97.0%, the lubricity is affected. The stability of the cleaning and the stability of the polishing effect may be lost.
[0021]
The rare earth element compound is oxide equivalent (CeO₂It is characterized by containing Ce in terms of 40.0 to 65.0 mass% (preferably 45.0 to 65.0 mass%, more preferably 50.0 to 63.0 mass%) in terms of polishing. The effect and the lubrication effect can be balanced, and stable developability can be obtained. When the Ce content exceeds 65.0% by mass, the amount of abrasion of the photoconductor becomes too large, shortening the life of the photoconductor, unevenness in the method of abrasion, loss of surface potential uniformity, and unevenness in image density. May occur. In addition, the toner may be excessively charged to cause a decrease in image density. On the other hand, if the Ce content is less than 40.0 mass%, the lubricity becomes poor and chattering and turning of the cleaning blade may occur. In addition, the chargeability of the toner may become uneven and the image density may become unstable.
[0022]
Further, the rare earth element compound is converted into oxide (La₂O_ThreeIn terms of La, it contains 25.0 to 45.0% by mass (preferably 27.0 to 43.0% by mass, more preferably 30.0 to 40.0% by mass). By containing La in the range, the fluidity of the toner can be stabilized, and in particular, the fluidity stabilizing effect in the cleaner of the waste toner is great. If the content of La is less than 25.0% by mass, the toner fluidity in the cleaner tends to be unstable. As a result, the toner leaks from the both ends of the cleaner blade onto the photoconductor, resulting in the fusion of the toner to the photoconductor end. On the other hand, if the La content exceeds 45.0% by mass, the fluidity becomes unstable and the movement of the waste toner in the cleaner becomes poor, so that the toner cannot be discharged well, and the toner may be clogged. Further, the blade edge portion may be clogged with toner, and the blade may be lifted to cause poor cleaning.
[0023]
Further, the rare earth element compound converts Nd into oxide (Nd₂O_Three1.0 to 10.0% by mass (in terms of conversion) (preferably 1.0 to 8.0% by mass, more preferably 2.0 to 5.0% by mass). By containing Nd, the retention of the inorganic fine powder A according to the present invention at the blade edge portion can be stabilized, the cleaning performance can be stabilized, and the cleaning failure can be prevented. Moreover, since the retention of the inorganic fine powder A is stabilized, fusion and image flow prevention are more effectively performed. When the above-mentioned rule is not satisfied, the inorganic fine powder A does not exist stably at the cleaner blade edge portion, so that aggregates generated in the cleaner are caught between the blade and the photosensitive member, and toner slip easily occurs. Further, the blade edge surface is exposed, a rapid change occurs in the friction coefficient, and the blade may vibrate, resulting in poor cleaning due to toner slippage. When the Nd content exceeds 10.0% by mass, the amount of inorganic fine powder transferred together with the toner particles increases, and supply to the blade edge portion may be lost. On the other hand, when the content of Nd is less than 1.0% by mass, the Nd content tends to move with the waste toner, and the stay in the blade edge portion may become unstable.
[0024]
In addition, the rare earth element compound has Pr converted to oxide (Pr₆O₁₁1.0 to 10.0% by mass (in terms of conversion) (preferably 2.0 to 9.0% by mass, more preferably 3.0 to 8.0% by mass). By containing Pr, charging stability of the toner is brought about. When the content of Pr exceeds 10.0% by mass, the inorganic fine powder A is likely to be overcharged, the electrostatic adhesion is increased, and the toner may be fused to the photoreceptor. If the Pr content is less than 1.0% by mass, the fine inorganic powder adsorbs fine toner particles to form fog particles, which may cause spotted fog.
[0025]
The inorganic fine powder A contains a rare earth element fluoride compound having a fluorine element content of 2.0 to 11.0 mass% (preferably 3.0 to 10.0 mass) based on the mass of the inorganic fine powder A. %, More preferably 4.0 to 9.0% by mass), and by containing the rare earth element fluoride within this range, the charge amount of the toner can be stabilized. Development durability stability can be obtained. In particular, in the case of a positively chargeable toner, the charge amount can be increased. When the content of fluorine element exceeds 11.0% by mass, when used in a negatively chargeable toner, the charge balance is liable to be lost, and image density is lowered and fog is likely to occur. Further, the abrasiveness may be insufficient. In addition, when the fluorine element content is less than 2.0% by mass of the present invention, when used in a positively chargeable toner, the charge balance tends to be lost, and image density reduction and fogging are likely to occur. In addition, the ratio of rare earth element oxide increases, which may increase the polishability and shorten the life of the photoreceptor.
[0026]
The inorganic fine powder A is preferably partially fluorinated with hydrofluoric acid after bastositeite ore is treated with oxidized rare earth. A normal bastosite abrasive is made from bastonesite ore by magnetic separation and flotation to make bastonesite concentrate, and the particle size is adjusted by grinding, drying, firing, re-grinding and classification to obtain an abrasive. The raw bust necite contains fluorine, and the obtained bust necite-based abrasive is an element of fluorine in the form of R—O—F (R: rare earth, O: oxygen atom, F: fluorine atom). Contains. However, by treating bastonite ore with rare earth oxides and fluoridating with hydrofluoric acid, fluorine elements are easily taken into the interior in the form of RF (R: rare earth, F: fluorine atom). , Moderate polishing properties can be obtained. In the inorganic fine powder A, rare earth elements are fluorinated uniformly, but lanthanum having strong basicity is more likely to be a fluoride, which keeps the charging stability of the toner good and has a concentration even in long-term use. There is no decline.
[0027]
The inorganic fine powder A preferably contains less than 100 ppm of uranium and thorium (preferably 10 ppm or less, particularly preferably 1 ppm or less). If it is contained more than this, the charging stability will be adversely affected, and particularly when used as a positively chargeable toner, the charge balance will be lost, resulting in reduced density and fogging.
[0028]
Further, in the present invention, the inorganic fine powder A has a volume average particle diameter of 0.1 to 4.0 μm (preferably 0.2 to 2.0 μm), and a BET specific surface area by a nitrogen gas adsorption method of 0.5 to 15.0m²/ G (preferably 1.0-10.0 m²/ G). When the volume average particle diameter is less than 0.1 μm, the cohesiveness of the inorganic fine powder A becomes high, and the fluidity of the toner tends to be adversely affected. Further, when the volume average particle diameter exceeds 4.0 μm, it is difficult to obtain the polishing effect. The BET specific surface area is 15.0m²When it exceeds / g, the moisture resistance of the inorganic fine powder A tends to decrease, and the developability particularly in a high humidity environment tends to decrease. Furthermore, BET specific surface area is 0.5m²When it is less than / g, it is difficult to obtain a polishing effect.
[0029]
Further, the toner of the present invention preferably contains 0.1 to 10.0% by mass of the inorganic fine powder A, more preferably 0.1 to 7.0% by mass. When the content of the inorganic fine particles A is less than 0.1% by mass, the effect is small and not preferable. Further, when the content of the inorganic fine particles A exceeds 10.0% by mass, the uneven distribution and release of the inorganic fine powder A easily occur in the toner, and the photoreceptor is shaved unevenly when used for a long time. However, the coefficient of friction on the surface of the photosensitive member varies, and cleaning failure is liable to occur.
[0030]
Furthermore, when the inorganic fine powder A of the present invention is used for a positively chargeable toner, the effect is sufficiently exhibited. Conventionally, there are strontium titanate and general cerium oxide as abrasives that are often used. However, when these abrasives are used for positively chargeable toners, they tend to cause insufficient charge amount or uneven charging. Usually, the binder resin used for toner is often negatively charged. When a positively chargeable toner is used, positively charged electrification is obtained by dispersing a positively chargeable charge control agent in the binder resin. Has obtained a good toner. Therefore, it is difficult to achieve a charge balance as compared with negatively chargeable toner. However, when the inorganic fine powder A of the present invention is used, uniform charging can be maintained without causing charging inhibition.
[0031]
The image forming method of the present invention uses the toner having the above-described configuration, but the performance is well exhibited when the image forming method uses an amorphous silicon photoconductor as a latent image carrier (photoconductor). . That is, contaminants on the surface of the amorphous silicon photoconductor having high hardness can be uniformly polished and removed, and further, charging of the toner is not hindered. Therefore, a stable image density can be obtained even in low potential development of the amorphous silicon photoconductor. Reduction of fog can be achieved.
[0032]
Furthermore, the image forming method of the present invention exhibits its performance well when the surface temperature of the photoreceptor is set to 45 ° C. or lower (more preferably 42 ° C. or lower). If the surface temperature of the photoconductor is lowered, the amount of water adhering to the surface of the photoconductor increases in a high-humidity environment, and it becomes easy to generate an image flow due to the combination of water and ozone deposits. By using the toner, the toner scrapes off the ozone adhering substance itself, so that it is difficult for image flow to occur. Furthermore, an image forming method that does not use a drum heater can be employed.
[0033]
Furthermore, the image forming method of the present invention exhibits its performance well when the cleaning member is a cleaning blade or a cleaning roller and a combination thereof. When used with the toner of the present invention, the inorganic fine powder A according to the present invention polishes the photoreceptor on the surface of the cleaning roller reasonably well, and is present at the cleaner blade edge, increasing the slip between the blade and the photoreceptor, The cleaning blade can be turned up and prevented from chattering, and the effect as an abrasive can be exhibited to remove the toner fused to the photoreceptor.
[0034]
Furthermore, the image forming method of the present invention exhibits its performance well when the cleaning roller encloses the magnetism generating means. In this case, since the toner is strongly attached to the cleaning roller by the magnetic force, the toner is agitated on the roller for a long time and aggregates are easily generated. Normally, the agglomerates are sandwiched between the cleaning blade and the photosensitive member to cause toner slipping, but the inorganic fine powder A according to the present invention is present at the edge of the cleaning blade and can prevent the intrusions from entering.
[0035]
Furthermore, the image forming method of the present invention exhibits good performance when the recording material (transfer material) conveying member is an elastic roller. For example, the problem that contaminants from the surface of the rubber-like roller stain the photoreceptor surface through the transfer material and cause image defects can also be used with the toner of the present invention to remove contaminants on the photoreceptor surface. There is no problem.
[0036]
As described above, the inorganic fine powder A used in the present invention has a better balance between the polishing property and the lubricity than the conventional general cerium oxide and strontium titanate, and stably cleans the photosensitive member with the cleaning member. And the occurrence of poor cleaning can be reduced.
[0037]
The characteristic value measuring method according to the present invention is as follows.
[0038]
(1) Content of rare earth element compounds
In the present invention, the content of the rare earth element compound in the inorganic fine powder A can be measured by an oxalate weight method. For example, about 0.5 g of sample, HClO_Four15 ml, H₂O₂Add 1 ml of solution, stir lightly, heat and decompose on a hot plate and concentrate to about 5 ml. Furthermore, about 50 ml of pure water is added and boiled, then filtered, and washed several times with warm water so that the filtrate becomes about 250 ml. While heating 250 ml of the obtained filtrate, oxalic acid 5.0 g was added and stirred to dissolve completely, and then allowed to cool to NH_FourThe pH is adjusted to 1.3 to 1.5 with OH and HCl. Thereafter, filtration and washing are performed, and the resulting precipitate is transferred to a porcelain crucible, dried at 140 ° C. for about 1 hour, and then ignited and incinerated at 1000 ° C. for about 1 hour in an electric furnace to form a rare earth compound. obtain. This is weighed, and the content is calculated from the initial weight of the inorganic fine powder A.
[0039]
(2) Content of each rare earth element in the rare earth element compound
In the present invention, the content of Ce, La, Nd, and Pr in the rare earth element compound is determined by plasma emission analysis (ICP) using the rare earth element compound obtained in (1) in accordance with JIS K0116 general rules for emission spectroscopy. Analysis) and calculated by oxide conversion. The contents of U and Th were obtained as element contents.
[0040]
(3) Elemental fluorine content of inorganic fine powder A
In the present invention, the fluorine element content of the inorganic fine powder A can be measured as follows. For example, 0.5 g of inorganic fine powder A is precisely weighed, and 5 ml of 50% by weight NaOH aqueous solution and 5 ml of pure water are added and dissolved by heating. After cooling, add pure water to make 100 ml, add 50 ml of it and 50 ml of buffer solution (100 ml of acetic acid, 116 g of sodium chloride and 2 g of sodium citrate dissolved in 1.5 liters of distilled water), and add to a 100 ml volumetric flask. Put it at a constant volume. About this aqueous solution, fluorine element content was measured with the ion meter.
[0041]
(4) Volume average particle size of inorganic fine powder
In the present invention, the volume average particle size of the inorganic fine powder A represents a volume particle size 50% value of laser diffraction particle size measurement (microtrack method).
[0042]
(5) BET specific surface area of inorganic fine powder
The BET specific surface area is obtained by the BET multipoint method using a fully automatic gas adsorption amount measuring apparatus: Auto Soap 1 manufactured by Yuasa Ionics Co., Ltd., using nitrogen as the adsorption gas. In addition, as pre-processing of a sample, deaeration for 6 hours is performed at 50 degreeC.
[0043]
The toner of the present invention further contains an inorganic fine powder B having a pH of 7 or more (more preferably 7.5 to 12.0, particularly 8.0 to 11.0), particularly in a low humidity environment. Good toner fluidity can be obtained. That is, by containing the inorganic fine powder B, it is possible to leak an excessive charge of the toner and keep the toner charge amount constant, to reduce electrostatic aggregation and to greatly improve the fluidity. When the pH is less than 7, it becomes difficult to perform triboelectric charge leakage generated from the toner and to universalize the charge via moisture. On the other hand, if the pH exceeds 12.0, charge leakage may become too large. That is, the pH of the inorganic fine powder B is brought about by a polar compound or a functional group on the surface of the fine powder, and when it exceeds a certain amount, it shows a pH of 7 or more. The polar substance or functional group that brings about this pH is the point of charge relaxation action. Such substances are brought about by substituents or reactive residues on the treatment agent. For example, when silazanes and silylamines are used, ammonia and amines play this role. When aminosilane or amino-modified silicone oil is used, the aminoalkyl group on silicon plays this role.
[0044]
That is, by setting the pH of the inorganic fine powder B to 7 or more, the density of the moisture adsorption point, the charge leak point, and the charge transfer point can be maintained in an effective state. Further, when the specific surface area of the inorganic fine powder B is increased, the effective range of the moisture adsorption point, the charge leak point, and the charge transfer point can be expanded. The preferable range of the BET specific surface area of the inorganic fine powder B will be described later.
[0045]
When the toner of the present invention is used in an image forming apparatus using an organic photoreceptor, it is preferable to contain inorganic fine powder C treated with silicone oil. Since the inorganic fine powder C improves the lubricating effect and makes the polishing effect mild, it is possible to perform good cleaning without excessively scraping or scratching the organic photoreceptor having low hardness. Further, by using the inorganic fine powder C, the photoreceptor can be polished more smoothly and good transferability can be maintained.
[0046]
Inorganic fine powders B and C used in the present invention include oxides, double oxides, metal oxides, metals, silicon compounds, carbon, carbon compounds, fullerenes, boron compounds, carbides, nitrides, silicides, and ceramics. Used, preferably a metal oxide. Of the metal oxides, silica, alumina, titania, and zirconia are particularly preferable. Further, silica that has a moderate charge leakage and has a stable charge relaxation action through moisture is particularly preferable.
[0047]
Silica used in the inorganic fine powders B and C includes a dry method by vapor phase oxidation of silicon halides (for example, thermal decomposition oxidation reaction in oxygen / hydrogen flame), sodium silicate, alkaline earth metal silicate, silicate. Silica obtained by a wet method using decomposition with acids, ammonia, salts, and alkali salts such as is preferably used, and an amorphous type is preferably used. By using together with metal halides and silicon halides such as aluminum chloride, titanium chloride, germanium chloride, tin chloride, zirconium chloride and lead chloride, fine powders of oxides of silicon and other metals can be obtained and used. . Among them, those produced by a dry method having not much internal surface area are preferably used because moisture adsorption is moderate.
[0048]
The titania used in the inorganic fine powders B and C is titania obtained by low-temperature oxidation (thermal decomposition, hydrolysis) of sulfuric acid method, chlorine method, volatile titanium compounds such as titanium alkoxide, titanium halide, titanium acetylacetonate. As the crystal system, any of anatase type, rutile type, mixed crystal type thereof, and amorphous type can be used. In particular, an amorphous material produced by low-temperature oxidation, an anatase type or mixed crystal type produced by a chlorine method or a sulfuric acid method is preferably used.
[0049]
Alumina used in the inorganic fine powders B and C is the buyer method, improved buyer method, ethylene chlorohydrin method, underwater spark discharge method, organoaluminum hydrolysis method, aluminum alum pyrolysis method, ammonium aluminum carbonate pyrolysis method, Alumina obtained by the flame decomposition method of aluminum chloride is used. As the crystal system, α, β, γ, δ, ξ, η, θ, κ, χ, ρ type, mixed crystal type, and amorphous type are used, and among them, α, γ, δ, θ, mixed type are used. Crystalline and amorphous materials are preferably used. In particular, γ and δ types produced by the thermal decomposition method and the flame decomposition method are preferably used.
[0050]
Since the inorganic fine powder B has a pH of 7 or more, a silazane compound that reacts or physically adsorbs with the inorganic fine powder, a silane compound in which a nitrogen atom is directly bonded to a silicon atom, a silane compound having a substituent containing a nitrogen element, It is treated with a silicone oil having a substituent containing elemental nitrogen. If necessary, for example, when a sufficient degree of hydrophobicity cannot be obtained with the treatment agent, those treated with a silane compound or silicone oil are also preferably used. For example, in order to further increase the degree of hydrophobicity, it may be treated with other organosilicon compounds, organotitanium compounds, and organoaluminum compounds, among which silane compounds, silicone oils, and silicone varnishes are preferably used. You may use a processing agent together.
[0051]
The inorganic fine powder C may be organically treated in addition to the silicone oil treatment, and as the treating agent, similarly to the inorganic fine powder B, an organic silicon compound or organic titanium that reacts or physically adsorbs with the inorganic fine powder. A compound and an organoaluminum compound are used, and a plurality of kinds of treatment agents may be used in combination.
[0052]
Examples of silazane compounds used for the surface treatment of inorganic fine powders B and C, and silane compounds in which nitrogen atoms are directly bonded to silicon atoms include hexamethyldisilazane, 1,3-bis (chloromethyl) -1,1. , 3,3-tetramethyldisilazane, bis (diethylamino) dimethylsilane, bis (dimethylamino) diphenylsilane, bis (dimethylamino) methylvinylsilane, bis (ethylamino) dimethylsilane, bis-N, N ′-(trimethylsilyl) ) Piperazine, t-butylaminotriethylsilane, t-butyldimethylaminosilane, t-butyldimethylsilylimidazole, t-butyldimethylsilylpyrrole, N, N'-diethylaminotrimethylsilane, 1,3-di-n-octyltetramethyl Disilazane, 1,3-diphenyltetra Tildisilazane, 1,3-divinyl-1,3-dimethyl-1,3-diphenyldisilazane, 1,3-divinyltetramethyldisilazane, heptamethyldisilazane, 1,1,3,3,5,5-hexa Methylcyclotrisilazane, nonamethyltrisilazane, octamethylcyclotetrasilazane, 1,1,3,3-tetramethyldisilazane, 2,2,5,5-tetramethyl-2,5-disila-1-azacyclo Pentane, 1,3,5,7-tetramethyl-1,3,5,7-tetravinylcyclotetrasilazane, 1,1,3,3-tetraphenyl-1,3-dimethyldisilazane, N-trimethylsilylimidazole N-trimethylsilylmorpholine, N-trimethylsilylpiperazine, N-trimethylsilylpyrrole, N-trimethylsilyltria Lumpur, 1,3,5-trimethyl-1,3,5-trivinyl cyclo bird silazane, hexaphenyl cyclo disilazane, silazanes to substituents siloxane units and the like. In particular, a silazane compound is preferably used because it has a high degree of hydrophobicity, easily adjusts the pH value, and easily balances between low humidity and high humidity.
[0053]
As a silane compound having a substituent containing a nitrogen element, a silane compound represented by the following general formula (1), a silane coupling agent having a substituent containing a nitrogen element, and a substituent containing a nitrogen element Examples thereof include siloxanes and silazanes having a substituent containing a nitrogen element.
[0054]
(R₁₁)_pSiY_4-p                                  ... (1)
Where R₁₁Represents an amino group or an organo group having at least one nitrogen atom, Y represents an alkoxy group or halogen, and p represents an integer of 1 to 3. Examples of the organo group having at least one nitrogen atom include groups having an amino group having an organic group as a substituent, a saturated nitrogen-containing heterocyclic group, and an unsaturated nitrogen-containing heterocyclic group. Examples of the heterocyclic group include those represented by the following formula. Of these, 5-membered and 6-membered rings are preferred from the viewpoint of stability.
[0055]
[Outside 1]

[0056]
Examples of the silane compound represented by the general formula (1) and a silane coupling agent having a nitrogen-containing substituent include aminopropyltrimethoxysilane, aminopropyltriethoxysilane, dimethylaminopropyltrimethoxysilane, and dimethylaminopropyl. Methyl diethoxysilane, diethylaminopropyltrimethoxysilane, dipropylaminopropyltrimethoxysilane, dibutylaminopropyltrimethoxysilane, monobutylaminopropyltrimethoxysilane, dioctylaminopropyltrimethoxysilane, dibutylaminopropylmethyldimethoxysilane, dibutylamino Propyldimethylmonomethoxysilane, dimethylaminophenyltriethoxysilane, trimethoxysilyl-γ-propylphenylamine, trimeth Sisilyl-γ-propylbenzylamine, trimethoxysilyl-γ-propylpiperidine, trimethoxysilyl-γ-propylmorpholine, trimethoxysilyl-γ-propylimidazole, γ-aminopropyldimethylmethoxysilane, γ-aminopropylmethyldimethoxysilane 4-aminobutyldimethylmethoxysilane, 4-aminobutylmethyldiethoxysilane, and N- (2-aminoethyl) aminopropyldimethylmethoxysilane.
[0057]
Examples of silazanes having substituents containing nitrogen elements include 1,3-bis (3-aminopropyl) -1,1,3,3-tetramethyldisilazane, 1,3-bis (4-amino). Butyl) -1,1,3,3-tetramethyldisilazane, 1,3-bis {N (2-aminoethyl) aminopropyl} -1,1,3,3-tetramethyldisilazane, 1,3- Bis (dimethylaminopropyl) -1,1,3,3-tetramethyldisilazane, 1,3-bis (diethylaminopropyl) -1,1,3,3-tetramethyldisilazane, 1,3-bis (3 -Propylaminopropyl) -1,1,3,3-tetramethyldisilazane, 1,3-bis (3-aminopropyl) -1,1,3,3-tetramethyldisilazane.
[0058]
Examples of siloxanes having substituents containing nitrogen element include 1,3-bis (3-aminopropyl) -1,1,3,3-tetramethyldisiloxane, 1,3-bis (4-amino) Butyl) -1,1,3,3-tetramethyldisiloxane, 1,3-bis {N (2-aminoethyl) aminopropyl} -1,1,3,3-tetramethyldisiloxane, 1,3- Bis (dimethylaminopropyl) -1,1,3,3-tetramethyldisiloxane, 1,3-bis (diethylaminopropyl) -1,1,3,3-tetramethyldisiloxane, 1,3-bis (3 -Propylaminopropyl) -1,1,3,3-tetramethyldisiloxane and 1,3-bis (3-aminopropyl) -1,1,3,3-tetramethyldisiloxane.
[0059]
Silicone oils having substituents containing nitrogen elements include silicone oils in which the substituents on the silicon atoms are hydrogen, methyl groups, phenyl groups, or alkyl groups in which some or all of the hydrogens are fluorine-substituted. And nitrogen-containing silicone oil in which a substituent having a nitrogen element is introduced into the side chain, both ends, one end, side chain one end, and both side chains of the polysiloxane skeleton. The substituent is preferably a substituent represented by the following formula.
[0060]
-R-NR₁₂R₁₃, -R'-NR₁₄-R "-NR₁₅R₁₆,
-R-R₁₇, -R-NR₁₄-R₁₇
In the formula, R, R ′, and R ″ represent a phenylene group and an alkylene group, and R₁₂, R₁₃, R₁₄, R₁₅, R₁₆Represents hydrogen, an optionally substituted alkyl group or an aryl group, and R₁₇Represents a nitrogen-containing heterocyclic ring. These substituents may take the form of ammonium salts.
[0061]
These nitrogen-containing silicone oils are substituted with epoxy groups, polyether groups, methylstyryl groups, alkyl groups, fatty acid ester groups, alkoxy groups, carboxyl groups, carbinol groups, methacrylic groups, mercapto groups, phenol groups, vinyl groups, etc. You may have group simultaneously.
[0062]
These nitrogen-containing silicone oils have a viscosity of 5,000 mm at 25 ° C.²/ S or less is preferable. 5,000mm²When it exceeds / s, dispersion becomes insufficient and uniform processing becomes difficult. Furthermore, the amine equivalent obtained by dividing the molecular weight by the number of amines per molecule is preferably 200 to 40,000, and more preferably 300 to 30,000. When the amine equivalent exceeds 40,000, the charge relaxation effect may be difficult to appear. When the amine equivalent is less than 200, charge leakage may increase excessively. Furthermore, it is possible to use a plurality of these nitrogen-containing silicone oils. Specific examples include amino-modified silicone oils and different functional group-modified silicone oils containing amino modification.
[0063]
Other silane compounds used for surface treatment of inorganic fine powders B and C include alkoxysilanes such as methoxysilane, ethoxysilane, and propoxysilane, halosilanes such as chlorosilane, bromosilane, and iodosilane, hydrosilanes, and alkyl. Silanes, aryl silanes, vinyl silanes, acrylic silanes, epoxy silanes, silyl compounds, siloxanes, silyl ureas, silyl acetamides, and silane compounds simultaneously having different substituents of these silane compounds Can be given. Specific examples thereof include trimethylsilane, trimethylchlorosilane, trimethylethoxysilane, dimethyldichlorosilane, methyltrichlorosilane, t-butyldimethylmethoxysilane, allyldimethylchlorosilane, allylphenyldichlorosilane, benzylmethyldichlorosilane, bromo. Methyldimethylchlorosilane, o-chloroethyltrichlorosilane, β-chloroethyltrichlorosilane, chloromethyldimethylchlorosilane, triorganosilylmercaptan, trimethylsilylmercaptan, triorganosilylacrylate, vinyldimethylacetoxysilane, dimethyldiethoxysilane, dimethyldimethoxy Silane, diphenyldiethoxysilane, N, O- (bistrimethylsilyl) acetamide, N, N-bis (trimethyl) Silyl) urea, hexamethyldisiloxane, 1,3-divinyltetramethyldisiloxane, 1,3-diphenyltetramethyldisiloxane, 2 to 12 siloxane units per molecule and silanol groups in the terminal units And dimethylpolysiloxane containing.
[0064]
Examples of other silicone oils for surface treatment of inorganic fine powders B and C include reactive silicones such as epoxy modification, carboxyl modification, carbinol modification, methacryl modification, mercapto modification, phenol modification, and heterofunctional group modification; polyether modification Non-reactive silicones such as methyl styryl modification, alkyl modification, fatty acid modification, alkoxy modification, and fluorine modification; straight silicones such as dimethyl silicone, methyl phenyl silicone, diphenyl silicone, and methyl hydrogen silicone.
[0065]
Among these silicone oils, non-reactive silicone and straight silicone are preferably used. Particularly preferable examples of the silicone oil for treating the inorganic fine powder C include dimethyl silicone and methyl hydrogen silicone.
[0066]
These silicone oils have a viscosity at 25 ° C. of 5 to 2,000 mm.²/ S is preferable. More preferably 10 to 1,000 mm²/ S. 5mm²If it is less than / s, the desired hydrophobicity may not be obtained.²If it exceeds / s, it may be difficult to uniformly process the inorganic fine powder, or aggregates may be easily formed and sufficient fluidity may not be obtained. A plurality of these silicone oils may be used.
[0067]
In particular, inorganic fine powders B and C have a specific surface area of 20 m according to the BET method.²/ G or more, more preferably 30 to 400 m.²/ G, particularly preferably 50 to 300 m²/ G. Specific surface area is 20m²If it is less than / g, the effect of charge leakage and charge delocalization will be inferior, and there may be a case where a large effect cannot be expected for the relaxation and uniformity of charge. The specific surface area is 400m²If it exceeds / g, the charge leakage may be too large.
[0068]
The content of the inorganic fine powders B and C of the present invention is preferably 0.05 to 2.0 parts by mass with respect to 100 parts by mass of the toner particles.
[0069]
In this invention, it is preferable that the processing amount of a processing agent with respect to 100 mass parts of processing base materials of the inorganic fine powders B and C is 1-40 mass parts, More preferably, it is 2-30 mass parts. When the amount is less than 1 part by mass, the treatment effect does not appear. When the amount exceeds 40 parts by mass, aggregates increase and the fluidity may decrease.
[0070]
When the treatment agent is a silane compound having a substituent having a nitrogen element, the treatment agent is preferably treated with 0.01 to 20 parts by weight, more preferably with respect to 100 parts by weight of the treatment base of the inorganic fine powder. It is 05-15 mass parts, Most preferably, it is 0.1-10 mass parts. If it is less than 0.01 parts by mass, the prevention of excessive charging due to charge leakage and the stability of both positive and negative charging tend to be insufficient. If the amount exceeds 20 parts by mass, charge leakage may increase, resulting in poor charging or insufficient charging under high humidity. In the case of negatively charged toner, generation of reverse polarity particles, positive charging In the case of a functional toner, overcharging and selective development are likely to occur.
[0071]
When the treatment agent is a silicone oil having a substituent having a nitrogen element, it is preferably treated with 0.1 to 30 parts by mass, more preferably with respect to 100 parts by mass of the inorganic fine powder. It is 2-20 mass parts, Most preferably, it is 0.5-15 mass parts. If the amount is less than 0.1 parts by mass, excessive charging due to charge leakage is prevented, and both positive and negative charging stability tends to be insufficient. If the amount exceeds 30 parts by mass, charge leakage may increase, resulting in poor charging or insufficient charging under high humidity. In the case of negatively chargeable toner, particles charged with a reverse polarity are generated. In the case of a positively chargeable toner, overcharging and selective development are likely to occur.
[0072]
When these several kinds of treatment agents are used, it is preferable that each treatment agent is used within the above range, and the combined treatment amount is 50 parts by mass or less with respect to 100 parts by mass of the inorganic fine powder treatment matrix. More preferably, it is 3-45 mass parts, Most preferably, it is 6-40 mass parts. When the amount of treatment exceeds 50 parts by mass, aggregates are generated or the treatment tends to be uneven.
[0073]
In the present invention, the pH of the inorganic fine powder is measured using a pH meter using a glass electrode. 4.0 g of sample is weighed into a beaker and 50 cm of remethanol^ThreeAnd wet the sample, and further 50cm of pure water^ThreeAnd stir well with a homomixer. Thereafter, the pH value is measured using a pH meter.
[0074]
Next, the toner particles according to the present invention will be described.
[0075]
As the binder resin used in the toner of the present invention, the following polymers can be used.
[0076]
For example, polystyrene; styrene-substituted homopolymers such as poly-p-chlorostyrene and polyvinyltoluene; styrene-p-chlorostyrene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene -Acrylic acid ester copolymer, styrene-methacrylic acid ester copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl ethyl ether Copolymers, styrene-vinyl methyl ketone copolymers, styrene-butadiene copolymers, styrene-isoprene copolymers, styrene copolymers such as styrene-acrylonitrile-indene copolymers; polyvinyl chloride, phenol resins, Naturally modified phenol Fat, natural resin modified maleic acid resin, acrylic resin, methacrylic resin, polyvinyl acetate, silicone resin, polyester resin, polyurethane, polyamide resin, furan resin, epoxy resin, xylene resin, polyvinyl butyral, terpene resin, coumarone indene resin, Petroleum resin is mentioned. Preferred binder resins include styrene copolymers or polyester resins.
[0077]
Examples of the comonomer for the styrene monomer of the styrene copolymer include acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, dodecyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, phenyl acrylate, and methacrylic acid. , Methyl methacrylate, ethyl methacrylate, butyl methacrylate, octyl methacrylate, acrylonitrile, methacrylonitrile, monocarboxylic acids having a double bond such as acrylamide or substituted products thereof; for example, maleic acid, butyl maleate, maleic acid Dicarboxylic acids having a double bond such as methyl and dimethyl maleate and substituted products thereof; vinyl esters such as vinyl chloride, vinyl acetate and vinyl benzoate; for example, ethylene, propylene and butylene Ethylenic olefins such as; for example, vinyl methyl ketone, vinyl ketones such as vinyl hexyl ketone; ethers such as vinyl methyl ether, vinyl ethyl ether, vinyl ethers such as vinyl isobutyl ether. These vinyl monomers are used alone or in combination of two or more.
[0078]
The styrenic polymer or styrenic copolymer may be cross-linked or a mixed resin.
[0079]
As the crosslinking agent for the binder resin, a compound having two or more polymerizable double bonds may be mainly used. For example, aromatic divinyl compounds such as divinylbenzene and divinylnaphthalene; carboxylic acid esters having two double bonds such as ethylene glycol diacrylate, ethylene glycol dimethacrylate, and 1,3-butanediol dimethacrylate; divinylaniline , Divinyl ether, divinyl sulfide, divinyl compounds such as divinyl sulfone; and compounds having three or more vinyl groups. These crosslinking agents are used alone or as a mixture.
[0080]
As a method for synthesizing the styrene copolymer, any of a bulk polymerization method, a solution polymerization method, a suspension polymerization method and an emulsion polymerization method may be used.
[0081]
In the bulk polymerization method, it is possible to obtain a low molecular weight polymer by polymerizing at a high temperature to increase the termination reaction rate, but there is a problem that the reaction is difficult to control. In the solution polymerization method, a low molecular weight polymer can be easily obtained under mild conditions by using the difference in chain transfer of radicals by a solvent and by adjusting the amount of initiator and reaction temperature. In the GPC chromatogram, It is preferable when obtaining a low molecular weight polymer having a maximum molecular weight in a molecular weight region of 5,000 to 100,000.
[0082]
As the solvent used in the solution polymerization, xylene, toluene, cumene, cellosolve acetate, isopropyl alcohol, and benzene are used. In the case of a styrene monomer mixture, xylene, toluene or cumene is preferred. It is appropriately selected depending on the polymer to be polymerized.
[0083]
The reaction temperature varies depending on the solvent to be used, the initiator, and the polymer to be polymerized, but it is preferably carried out at 70 to 230 ° C. The solution polymerization is preferably performed with 30 to 400 parts by mass of the monomer with respect to 100 parts by mass of the solvent.
[0084]
Furthermore, it is also preferable to mix other polymers in the solution at the end of the polymerization, and several polymers can be mixed well.
[0085]
In addition, as a polymerization method for obtaining a high molecular weight polymer or a crosslinked polymer having a maximum molecular weight in the region of 300,000 to 5,000,000 in the GPC chromatogram, an emulsion polymerization method or a suspension polymerization method is preferable.
[0086]
Among them, the emulsion polymerization method is a method in which a monomer (monomer) almost insoluble in water is dispersed as small particles in an aqueous phase with an emulsifier, and polymerization is performed using a water-soluble polymerization initiator. In this method, the heat of reaction can be easily adjusted, and since the phase in which the polymerization is carried out (oil phase consisting of polymer and monomer) and the aqueous phase are different, the termination reaction rate is low, and as a result, the polymerization rate is high. A product having a high degree of polymerization is obtained. Furthermore, the reason is that the polymerization process is relatively simple, and that the polymerization product is fine particles, so that it is easy to mix with colorants, charge control agents and other additives in the production of toner. Therefore, the method for producing the binder resin for toner is more advantageous than other methods.
[0087]
However, the added polymer is easily impure due to the added emulsifier, and suspension polymerization is a simple method because an operation such as salting out is required to take out the polymer.
[0088]
In suspension polymerization, it is good to carry out by 100 mass parts or less (preferably 10-90 mass parts) of monomers with respect to 100 mass parts of aqueous medium. As a usable dispersant, polyvinyl alcohol, polyvinyl alcohol partially saponified product, calcium phosphate is used, and there is an appropriate amount such as a monomer amount with respect to the aqueous medium, but generally 0.05 to 1 mass with respect to 100 parts by mass of the aqueous medium. Used in the department. The polymerization temperature is suitably 50 to 95 ° C., but should be appropriately selected depending on the polymerization initiator used and the target polymer. Any kind of polymerization initiator can be used as long as it is insoluble or hardly soluble in water.
[0089]
As polymerization initiators used in these polymerization methods, t-butylperoxy-2-ethylhexanoate, cumin perpivalate, t-butylperoxylaurate, benzoyl peroxide, lauroyl peroxide, octanoyl peroxide Oxide, di-t-butyl peroxide, t-butylcumyl peroxide, dicumyl peroxide, 2,2′-azobisisobutyronitrile, 2,2′-azobis (2-methylbutyronitrile), 2 , 2′-azobis (2,4-dimethylvaleronitrile), 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile), 1,1-bis (t-butylperoxy) 3,3 , 5-trimethylcyclohexane, 1,1-bis (t-butylperoxy) cyclohexane, 1,4-bis ( -Butyl peroxycarbonyl) cyclohexane, 2,2-bis (t-butylperoxy) octane, n-butyl 4,4-bis (t-butylperoxy) valerate, 2,2-bis (t-butylperoxy) ) Butane, 1,3-bis (t-butylperoxy-isopropyl) benzene, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, 2,5-dimethyl-2,5-di (T-butylperoxy) hexane, 2,5-dimethyl-2,5-di (benzoylperoxy) hexane, di-t-butyldiperoxyisophthalate, 2,2-bis (4,4-di-) t-butylperoxycyclohexyl) propane, di-t-butylperoxy α-methylsuccinate, di-t-butylperoxydimethylglutarate, di-t-butylper Oxyhexahydroterephthalate, di-t-butylperoxyazelate, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, diethylene glycol-bis (t-butylperoxycarbonate), di-t -Butylperoxytrimethyladipate, tris (t-butylperoxy) triazine, vinyltris (t-butylperoxy) silane. These polymerization initiators can be used alone or in combination.
[0090]
The amount used is 0.05 parts by mass or more (preferably 0.1 to 15 parts by mass) with respect to 100 parts by mass of the monomer.
[0091]
When a polyester resin is used as the binder resin, the composition of the polyester resin is as follows.
[0092]
Examples of the divalent alcohol component include ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, diethylene glycol, triethylene glycol, 1,5-pentanediol, 1, 6-hexanediol, neopentyl glycol, 2-ethyl-1,3-hexanediol, hydrogenated bisphenol A, and bisphenol represented by formula (A) and derivatives thereof;
[0093]
[Outside 2]

(In the formula, R represents an ethylene or propylene group, x and y are each an integer of 0 or more, and the average value of x + y is 0 to 10.)
[0094]
In addition, diols represented by the formula (B);
[0095]
[Outside 3]

Wherein R ′ is —CH₂CH₂-Or
[0096]
[Outside 4]

X ′ and y ′ are integers of 0 or more, and the average value of x ′ + y ′ is 0-10. ).
[0097]
Examples of the divalent acid component include benzenedicarboxylic acids such as phthalic acid, terephthalic acid, isophthalic acid, and phthalic anhydride or anhydrides thereof, lower alkyl esters; alkyl dicarboxylic acids such as succinic acid, adipic acid, sebacic acid, and azelaic acid. Acids or anhydrides thereof, lower alkyl esters; alkenyl succinic acids or alkyl succinic acids such as n-dodecenyl succinic acid and n-dodecyl succinic acid, or anhydrides, lower alkyl esters thereof; fumaric acid, maleic acid, citraconic acid, itaconic acid And dicarboxylic acids such as lower alkyl esters and derivatives thereof.
[0098]
Moreover, it is preferable to use together the trihydric or more alcohol component and trivalent or more acid component which work also as a crosslinking component.
[0099]
Examples of the trihydric or higher polyhydric alcohol component include sorbitol, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, 1,2,4-butane. Triol, 1,2,5-pentanetriol, glycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, 1,3,5-trihydroxybenzene Can be mentioned.
[0100]
Examples of the trivalent or higher polyvalent carboxylic acid component include trimellitic acid, pyromellitic acid, 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, and 2,5,7-naphthalene. Tricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 1,2,4-butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2-methylenecarboxypropane, Tetra (methylenecarboxyl) methane, 1,2,7,8-octanetetracarboxylic acid, empole trimer acid, and anhydrides, lower alkyl esters thereof;
Next formula
[0101]
[Outside 5]

(In the formula, X represents an alkylene group or alkenylene group having 1 to 30 carbon atoms having one or more side chains having 1 or more carbon atoms)
And polycarboxylic acids such as anhydrides and lower alkyl esters thereof and derivatives thereof.
[0102]
It is preferable to use 40 to 60 mol%, preferably 45 to 55 mol% as the alcohol component, and 60 to 40 mol%, preferably 55 to 45 mol% as the acid component.
[0103]
Moreover, it is also preferable that the polyvalent component more than trivalence is 1-60 mol% in all the components.
[0104]
In the toner of the present invention, in addition to the above binder resin component, silicone resin, polyurethane, polyamide, epoxy resin, polyvinyl butyral, rosin, modified rosin, terpene resin, phenol in a proportion less than the content of the binder resin component. Resin, a copolymer resin component of two or more α-olefins can be contained.
[0105]
The glass transition point (Tg) of the binder resin used in the toner of the present invention is preferably 45 to 80 ° C, more preferably 50 to 70 ° C.
[0106]
In the present invention, it is preferable to contain a wax in order to improve low-temperature fixability and high-temperature offset resistance.
[0107]
The wax contained in the toner of the present invention is a low molecular weight polyethylene, a low molecular weight polypropylene, an olefin copolymer, an aliphatic hydrocarbon wax such as microcrystalline wax, paraffin wax, or sazol wax; a fat such as oxidized polyethylene wax. Oxides of aromatic hydrocarbon waxes or block copolymers thereof; waxes based on fatty acid esters such as carnauba wax and montanate wax; part or all of fatty acid esters such as deoxidized carnauba wax Is obtained by deoxidizing. In addition, saturated linear fatty acids such as palmitic acid, stearic acid, montanic acid, or long-chain alkyl carboxylic acids having a long-chain alkyl group; unsaturated fatty acids such as brandic acid, eleostearic acid, and valinal acid; Saturated alcohols such as stearic alcohol, aralkyl alcohol, behenyl alcohol, carnauvyl alcohol, seryl alcohol, melyl alcohol, or long-chain alkyl alcohols having a long-chain alkyl group; polyhydric alcohols such as sorbitol; linoleic acid Fatty acid amides such as amides, oleic acid amides, lauric acid amides; saturated fatty acid vinyls such as methylene bisstearic acid amides, ethylene biscapric acid amides, ethylene bislauric acid amides, hexamethylene bisstearic acid amides. Amides, unsaturated fatty acid amides such as ethylene bisoleic acid amide, hexamethylene bisoleic acid amide, N, N′-dioleyl adipic acid amide, N, N′-dioleyl sebacic acid amide; Aromatic bisamides such as acid amides and N, N'-distearylisophthalamide; waxes grafted to aliphatic hydrocarbon waxes using vinyl monomers such as styrene and acrylic acid; behenic acid monoglycerides Examples include partially esterified products of fatty acids and polyhydric alcohols such as: methyl ester compounds having a hydroxy group obtained by hydrogenating vegetable oils and fats.
[0108]
As the wax preferably used, a low molecular weight alkylene polymer obtained by polymerizing alkylene with radical polymerization under high pressure or a Ziegler catalyst or other catalyst under low pressure; an alkylene polymer obtained by thermally decomposing a high molecular weight alkylene polymer; A low molecular weight alkylene polymer produced as a by-product during polymerization of the alkylene polymer is separated and purified; from the distillation residue of hydrocarbons obtained by the age method from a synthesis gas composed of carbon monoxide and hydrogen, or by hydrogenating them. A wax obtained by extracting and fractionating a specific component from the resulting synthetic hydrocarbon is exemplified. These waxes may contain an antioxidant. Furthermore, a wax formed from a linear alcohol, a fatty acid, an acid amide, an ester, or a montan derivative may be mentioned. Further, those from which impurities such as fatty acids have been removed in advance are also preferred.
[0109]
Among them, preferred are those obtained by polymerizing olefins such as ethylene, and by-products at this time, such as Fischer-Tropsch wax, based on hydrocarbons having up to about several thousand carbon atoms. A long-chain alkyl alcohol having a hydroxyl group at the terminal having up to several hundred carbon atoms is also preferred. Furthermore, what added the alkylene oxide to alcohol is also used preferably.
[0110]
From these waxes, the wax is fractionated by molecular weight using a press sweating method, a solvent method, vacuum distillation, supercritical gas extraction method, fractional crystallization (for example, fused liquid crystal deposition and crystal filtration), etc. A wax having a sharp molecular weight distribution is more preferred because the proportion of components in the required melting behavior range increases. Among them, the use of two or more kinds of waxes separated in this manner can provide a wax component having a melting behavior range necessary for improving these properties in a well-balanced manner with respect to low-temperature fixability, blocking resistance and high-temperature offset resistance. This is particularly preferable because it can be contained in the toner without waste.
[0111]
The toner of the present invention preferably contains a charge control agent.
[0112]
The following substances are used for controlling the toner to be positively charged.
[0113]
Modified products with nigrosine and fatty acid metal salts; onium salts such as quaternary ammonium salts such as tributylbenzylammonium-1-hydroxy-4-naphthosulfonate, tetrabutylammonium tetrafluoroborate, and phosphonium salts which are analogs thereof And these lake pigments, triphenylmethane dyes and these lake pigments. Compound) metal salt of higher fatty acid; diorganotin oxide such as dibutyltin oxide, dioctyltin oxide, dicyclohexyltin oxide; dibutyltin borate, dioctyltin borate, dicyclohexyltin Such diorgano tin borate such rate; guanidine compounds, and imidazole compounds. These can be used alone or in combination of two or more. Among these, triphenylmethane compounds, imidazole compounds, and quaternary ammonium salts whose counter ions are not halogen are preferably used.
[0114]
Also, general formula (1)
[0115]
[Outside 6]

A copolymer of the monomer and a polymerizable monomer such as styrene, acrylic acid ester or methacrylic acid ester described above can also be used as a positive charge control agent. In this case, these charge control agents also have an action as a binder resin (all or a part thereof).
[0116]
In particular, a triphenylmethane compound represented by the following general formula (2) is preferable in the configuration of the present invention.
[0117]
[Outside 7]

[0118]
The following substances are used for controlling the toner to be negatively charged.
[0119]
For example, an organometallic complex and a chelate compound are effective, and there are a monoazo metal complex, an acetylacetone metal complex, an aromatic hydroxycarboxylic acid, and an aromatic dicarboxylic acid-based metal compound. Others include aromatic hydroxycarboxylic acids, aromatic mono and polycarboxylic acids and their metal salts, anhydrides, esters; phenol derivatives such as bisphenols.
[0120]
The azo metal complex represented by the following general formula (3) is preferred.
[0121]
[Outside 8]

[0122]
In particular, the central metal M is preferably Fe or Cr, and the substituent is preferably a halogen, an alkyl group, or an anilide group.
[0123]
Alternatively, a basic organic acid metal compound represented by the following general formula (4) is also preferable as the negative charge control agent.
[0124]
[Outside 9]

[0125]
In particular, the central metal is preferably Fe, Cr, Si, Zn or Al, and the substituent is preferably C.₁~ C₁₈Are preferably an alkyl group, an anilide group, an aryl group, a halogen atom, particularly an alkyl group or a halogen atom, and the cation is preferably a hydrogen ion, an ammonium ion, or an aliphatic ammonium ion.
[0126]
As a method for adding the charge control agent to the toner, there are a method of adding the charge control agent inside the toner and a method of adding the charge control agent externally. The amount of use of these charge control agents is determined by the toner production method including the type of binder resin, the presence or absence of other additives, and the dispersion method, and is not uniquely limited. Preferably, it is used in the range of 0.1 to 10 parts by mass, more preferably 0.1 to 5 parts by mass with respect to 100 parts by mass of the binder resin.
[0127]
Moreover, carbon black, aniline black, acetylene black, titanium white, and all other pigments and / or dyes can be used as the colorant regardless of one component or two components.
[0128]
For example, when the toner of the present invention is used as a magnetic color toner, examples of the dye include C.I. I. Direct Red 1, C.I. I. Direct Red 4, C.I. I. Acid Red 1, C.I. I. Basic Red 1, C.I. I. Modern Tread 30, C.I. I. Direct Blue 1, C.I. I. Direct Blue 2, C.I. I. Acid Blue 9, C.I. I. Acid Blue 15, C.I. I. Basic Blue 3, C.I. I. Basic Blue 5, C.I. I. Modern Blue 7, C.I. I. Direct Green 6, C.I. I. Basic Green 4, C.I. I. Basic green 6 can be used. As pigments, yellow lead, cadmium yellow, mineral fast yellow, navel yellow, naphthol yellow S, Hansa yellow G, permanent yellow NCG, tartra gin lake, red mouth yellow lead, molybdenum orange, permanent orange GTR, pyrazolone orange, benzidine orange G , Cadmium Red, Permanent Red 4R, Watching Red Calcium Salt, Eosin Lake, Brilliant Carmine 3B, Manganese Purple, Fast Violet B, Methyl Violet Lake, Bitumen, Cobalt Blue, Alkaline Blue Lake, Victoria Blue Lake, Phthalocyanine Blue, Fast Sky Blue, Indanthrene Blue BC, Chrome Green, Chrome Oxide, Pigment Green B, Malachite Green Lake, It can be used § Lee Naru yellow green G.
[0129]
Further, when the toner of the present invention is used as a two-component full color toner, the following may be mentioned.
[0130]
Examples of the color pigment for magenta include C.I. I. Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 30, 31, 32, 37, 38, 39, 40, 41, 48, 49, 50, 51, 52, 53, 54, 55, 57, 58, 60, 63, 64, 68, 81, 83, 87, 88, 89, 90, 112, 114, 122, 123, 163, 202, 206, 207, 209, C.I. I. Pigment violet 19, C.I. I. Buttred 1, 2, 10, 13, 15, 23, 29, 35 may be mentioned.
[0131]
Such a magenta color pigment may be used alone, but it is more preferable to improve the sharpness in combination with a magenta dye from the viewpoint of the image quality of a full-color image. Such magenta dyes include C.I. I. Solvent Red 1, 3, 8, 23, 24, 25, 27, 30, 49, 81, 82, 83, 84, 100, 109, 121, C.I. I. Disper thread 9, C.I. I. Solvent Violet 8, 13, 14, 21, 27, C.I. I. Oil-soluble dyes such as disperse violet 1, C.I. I. Basic Red 1, 2, 9, 12, 13, 14, 15, 17, 18, 22, 23, 24, 27, 29, 32, 34, 35, 36, 37, 38, 39, 40, C.I. I. Basic dyes such as basic violet 1,3,7,10,14,15,21,25,26,27,28 can be mentioned.
[0132]
As other coloring pigments, cyan pigments include C.I. I. Pigment blue 2, 3, 15, 16, 17, C.I. I. Bat Blue 6, C.I. I. Acid Blue 45 or a copper phthalocyanine pigment obtained by substituting 1 to 5 phthalimidomethyl groups on a phthalocyanine skeleton having a structure represented by the following formula.
[0133]
[Outside 10]

[0134]
Examples of the color pigment for yellow include C.I. I. Pigment Yellow 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 15, 16, 17, 23, 65, 73, 83, C.I. I. Butt yellow 1,3,20 is mentioned.
[0135]
The amount of these colorants used is 0.1 to 60 parts by weight, preferably 0.1 to 50 parts by weight, more preferably 0.1 to 20 parts by weight, with respect to 100 parts by weight of the binder resin. Especially preferably, it is 0.3-10 mass parts.
[0136]
In the toner of the present invention, a magnetic material can be used as a colorant, and the toner can be used as a magnetic toner.
[0137]
Furthermore, when the toner of the present invention is used as a magnetic toner and is used as a one-component developer, the magnetic material includes magnetite, hematite, iron oxide of ferrite; Examples include alloys with metals such as cobalt, copper, lead, magnesium, tin, zinc, antimony, beryllium, bismuth, cadmium, calcium, manganese, selenium, titanium, tungsten, vanadium, and mixtures thereof.
[0138]
These magnetic materials preferably have an average particle size of 2 μm or less, preferably about 0.1 to 0.5 μm. The amount to be contained in the toner is preferably 20 to 200 parts by mass, particularly preferably 40 to 150 parts by mass with respect to 100 parts by mass of the binder resin.
[0139]
Further, the saturation magnetization of these magnetic materials is 7.96 × 10 6.²5 to 200 Am in a magnetic field of kA / m (10 kOe)²/ Kg (emu / g), further 10-150 Am²/ Kg (emu / g) is preferable.
[0140]
The residual magnetization of the magnetic material is 7.96 × 10²1-100 Am in a magnetic field of kA / m (10 kOe)²/ Kg (emu / g), further 1-70 Am²/ Kg (emu / g) is preferable.
[0141]
The magnetic property of the magnetic material is “vibrating sample type magnetometer VSM-3S-15” (manufactured by Toei Kogyo Co., Ltd.) and an external magnetic field of 7.96 × 10.²It is a value measured under kA / m (10 kOe).
[0142]
The toner of the present invention is used by mixing with carrier powder when used as a two-component developer. In this case, the mixing ratio of the toner and the carrier powder is 0.1 to 50% by mass, preferably 0.5 to 10% by mass, and more preferably 3 to 10% by mass as the toner concentration. As the carrier that can be used in the present invention, any conventionally known carrier can be used. Specifically, a surface oxidation or non-oxidation metal such as iron, nickel, cobalt, manganese, chromium, rare earth, and Those alloys or oxides can be used, and particles having an average particle diameter of 20 to 300 μm are preferably used.
[0143]
Further, those obtained by adhering or coating a resin such as a styrene resin, an acrylic resin, a silicone resin, a fluorine resin, or a polyester resin on the surface of the carrier particles are preferably used.
[0144]
In order to prepare the toner particles according to the present invention, a binder resin, a magnetic material, a wax, a charge control agent, and other additives are sufficiently mixed by a mixer such as a Henschel mixer and a ball mill, and then heated rolls and kneaders. In addition, the components can be dispersed or dissolved in a melted and kneaded resin using a heat kneader such as an extruder, and the toner particles according to the present invention can be obtained by cooling, solidifying and classifying. it can.
[0145]
The toner according to the present invention can be obtained by sufficiently mixing inorganic fine powder and other additives with the obtained toner particles by a mixer such as a Henschel mixer.
[0146]
In the present invention, the weight average particle diameter of the toner is preferably 4 to 13 μm, more preferably 5 to 12 μm. When the weight average particle diameter of the toner is less than 4 μm, it is difficult to obtain a sufficient image density. If it exceeds 13 μm, it is difficult to form a higher definition image.
[0147]
The weight average particle diameter of the toner is measured using a Coulter Counter TA-II type (manufactured by Coulter), but a Coulter multisizer (manufactured by Coulter) can also be used. As the electrolytic solution, a 1% NaCl aqueous solution is prepared using primary sodium chloride. For example, ISOTON R-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 electrolytic solution in which the sample is suspended is subjected to a dispersion process for about 1 to 3 minutes with an ultrasonic disperser, and the volume and the number of toners of 2.00 μm or more are measured by using the 100 μm aperture as the aperture by the measuring device. Distribution and number distribution were calculated. Then, a weight-based weight average particle diameter (D_Four(The median value of each channel is the representative value for each channel).
[0148]
As channels, 2.00 to less than 2.52 μm; 2.52 to less than 3.17 μm; 3.17 to less than 4.00 μm; 4.00 to less than 5.04 μm; 5.04 to less than 6.35 μm; 6 Less than 35 to 8.00 μm; less than 8.00 to less than 10.08 μm; less than 10.08 to less than 12.70 μm; less than 12.70 to less than 16.00 μm; less than 16.00 to less than 20.20 μm; 13 channels of less than 40 μm; 25.40 to less than 32.00 μm; 32.00 to less than 40.30 μm were used.
[0149]
When forming an image using the toner of the present invention, it is preferable to use an a-Si photosensitive member having an a-Si layer as a photosensitive layer on a conductive substrate as the electrostatic charge image holding member.
[0150]
As a configuration of the a-Si photosensitive member, a lower charge injection preventing layer is provided below the photosensitive layer to prevent the ingress of charges from the substrate. In order to further improve durability, a surface protective layer is formed on the photosensitive layer, and an upper charge injection preventing layer that prevents injection of latent image charges from the surface of the electrostatic charge image holding member is formed on the photosensitive layer or on the surface protective layer. It can also be provided between the layers. Further, a layer serving as a surface protective layer and an upper charge injection preventing layer may be provided on the photosensitive layer. Further, a long wavelength light blocking layer may be provided to prevent the occurrence of interference development of long wavelength light.
[0151]
When providing each of these layers, in order to adapt the characteristics of each layer to practical use as needed, periodic groups such as hydrogen atoms, Group III atoms such as boron, aluminum and gallium, germanium and tin are used. Group IV atoms, group V atoms such as nitrogen, phosphorus and arsenic, group VI atoms such as oxygen, sulfur and selenium, and halogen atoms such as fluorine, chlorine and bromine alone or in combination. Introduced during the formation of a-Si, each characteristic can be controlled.
[0152]
For example, a lower charge injection preventing layer composed of an a-Si: H film doped with phosphorus (P) in hydrogenated a-Si (a-Si: H), and a non-doped a-Si: H film. A desired amorphous silicon that retains a negatively charged electrostatic charge image by providing a photosensitive layer and an upper charge injection preventing layer composed of an a-Si: film doped with boron (B) on the drum substrate in this order. A photosensitive drum can be obtained.
[0153]
Similarly, a lower charge injection prevention layer composed of an a-Si: H film doped with boron, a photosensitive layer composed of a non-doped a-Si: H film, and a silicon film composed of silicon, carbon and hydrogen ( That is, by providing a surface protective layer composed of an a-SiC: H film) on the drum substrate in this order, a desired amorphous silicon photosensitive drum holding a positive charge can be obtained.
[0154]
With such an a-Si photoreceptor, an electrostatic charge image holder having spectral sensitivity from visible light to semiconductor laser light can be obtained. By using the electrostatic charge image holder, a laser spot from a semiconductor laser or the like can be obtained. A digital latent image can be formed on the electrostatic charge image holding member.
[0155]
Next, the image forming method of the present invention will be described.
[0156]
Next, the image forming method of the present invention will be described with reference to FIG. The surface of the latent image carrier (photoconductor) 1 is charged negatively or positively by the primary charger 2, and an electrostatic charge image (for example, a digital latent image by image scanning) is formed by analog exposure or laser light exposure 5. Then, the electrostatic image is developed by reversal development or normal development with the toner 13 of the developing device 10 having the developing sleeve 4. In the developing unit, an alternating bias, a pulse bias, and / or an AC bias is applied between the photosensitive member 1 and the developing sleeve 4 by the bias applying unit 12. The toner image is transferred to the transfer material conveyed by the conveyance roller 14 with or without the intermediate transfer member (in FIG. 1, the case where the intermediate transfer member is not interposed). When the transfer paper P is conveyed and arrives at the transfer section, the transfer charger 3 charges the positive or negative polarity from the back surface (the opposite surface to the photoconductor side) of the transfer paper P by the transfer charger 3. The electrostatic toner image or the positively charged toner image is electrostatically transferred onto the transfer paper P. The transfer paper P separated from the photoreceptor 1 is fixed on the toner image on the transfer paper P by a heat and pressure roller fixing device 7 including a heater 16. The toner remaining on the photoreceptor 1 after the transfer process is removed by a cleaning unit having a cleaning blade 8 and a cleaning roller 9. After the cleaning, the photoreceptor 1 is neutralized by the erase exposure 6, and the process starting from the charging process by the primary charger 2 is repeated again.
[0157]
Next, the developing device will be described in detail.
[0158]
In FIG. 2, the developing device X1 rotates an electrostatic latent image holding body that holds an electrostatic latent image formed by a known process, for example, the electrophotographic photosensitive drum 1 in the arrow B direction. The developing sleeve 4 as the developer carrying member carries the toner 13 supplied from the hopper 17 as the developing container, and rotates in the direction of arrow A, so that the developing sleeve 4 and the photosensitive drum 1 face each other. The toner 13 is conveyed to D. A magnet 15 is disposed in the developing sleeve 4 in order to magnetically attract and hold the toner 13 on the developing sleeve 4. The toner 13 obtains a triboelectric charge that can develop the electrostatic latent image on the photosensitive drum 1 by friction with the developing sleeve 4.
[0159]
In order to regulate the layer thickness of the toner 13 conveyed to the developing section D, the regulating blade 11 as a developer layer thickness regulating member made of a ferromagnetic metal has a gap width of about 200 to 300 μm from the surface of the developing sleeve 4. It is suspended from the hopper 17 so as to face the developing sleeve 4. A magnetic force line from the magnetic pole N 1 of the magnet 15 concentrates on the regulating blade 11, whereby a thin layer (developer layer) of the toner 13 is formed on the developing sleeve 4. As the regulating blade 11, either magnetic or non-magnetic blades can be used.
[0160]
The thickness of the thin layer of toner 13 formed on the developing sleeve 4 is preferably thinner than the minimum gap between the developing sleeve 4 and the photosensitive drum 1 in the developing portion D. The present invention is particularly effective for a developing device that develops an electrostatic latent image with such a thin toner layer, that is, a non-contact developing device. However, the present invention can also be applied to a developing device in which the thickness of the toner layer in the developing portion is equal to or greater than the minimum gap between the developing sleeve 4 and the photosensitive drum 1, that is, a contact type developing device.
[0161]
In order to avoid complicated explanation, the following explanation will be made with reference to a non-contact type developing apparatus.
[0162]
A developing bias voltage is applied to the developing sleeve 4 by the bias applying means 12 in order to cause the toner 13 as the developer carried on the developing sleeve 4 to fly. When a DC voltage is used as the developing bias voltage, a voltage having a value between the potential of the image portion of the electrostatic latent image (the region visualized by adhesion of the toner 13) and the potential of the background portion is the developing sleeve. 4 is preferably applied. On the other hand, in order to increase the density of the developed image or improve the gradation, an alternating bias voltage may be applied to the developing sleeve 4 to form an oscillating electric field whose direction is alternately reversed in the developing portion D. In this case, it is preferable that an alternating bias voltage on which a DC voltage component having a value between the potential of the image portion and the background portion is superimposed is applied to the developing sleeve 4.
[0163]
In the so-called regular development, in which the toner is attached to the high potential portion of the electrostatic latent image having a high potential portion and a low potential portion and visualized, toner charged to a polarity opposite to that of the electrostatic latent image is used, In so-called reversal development in which toner is attached to a low potential portion of an electrostatic latent image for visualization, toner that is charged with the same polarity as the polarity of the electrostatic latent image is used. The high potential and the low potential are expressed by absolute values. In any case, the toner 13 is charged to a polarity for developing the electrostatic latent image by friction with the developing sleeve 4.
[0164]
FIG. 3 is a block diagram showing another embodiment of the developing device.
[0165]
In the developing device X2 of FIG. 3, as a developer layer thickness regulating member for regulating the layer thickness of the toner 13 on the developing sleeve 4, a material having rubber elasticity such as urethane rubber and silicone rubber, or phosphor bronze and stainless steel A feature is that an elastic plate 18 made of a material having metal elasticity such as steel is used, and the elastic plate 18 is pressed against the developing sleeve 4. In such a developing device, a thinner toner layer can be formed on the developing sleeve 4. The other configuration of the developing device X2 in FIG. 3 is basically the same as that of the developing device X1 shown in FIG. 2, and the same reference numerals as those in FIG. 2 in FIG. 3 denote the same members.
[0166]
The developing device X2 as shown in FIG. 3 that forms the toner layer on the developing sleeve 4 as described above rubs the toner on the developing sleeve 4 by the elastic plate 18, so that the triboelectric charge amount of the toner also increases. The image density is improved. In particular, in a non-magnetic one-component developer, a developing device using such an elastic plate is preferably used.
[0167]
【Example】
EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this does not limit this invention at all.
[0168]
(Production Examples 1 to 7 and Comparative Production Examples 1 and 2 of inorganic fine powder A)
The bastonite concentrate is pulverized and dissolved in sulfuric acid, and then the amount of each rare earth element is adjusted by solvent extraction, and then a rare earth element carbonate is formed and fired to obtain a rare earth oxide compound. After allowing to cool, hydrofluoric acid is added so that the fluorine content is as shown in Table 1 while performing wet pulverization, and after drying, firing in an electric furnace at 600 to 1000 ° C. for 5 to 10 hours, Through the classification step, inorganic fine powders A-1 to A-7 of Production Examples 1 to 7 and inorganic fine powders a-1 and a-2 of Comparative Production Examples 1 to 2 as shown in Table 1 were obtained.
[0169]
(Comparative Production Example 3 of Inorganic Fine Powder)
The bastonite concentrate is beneficiated, pulverized and dried, and baked in an electric furnace at 600 to 1000 ° C. for 5 to 10 hours, followed by a pulverization and classification step, and the inorganic fine powder a-3 of Comparative Production Example 3 Obtained. Table 1 shows the composition of the obtained inorganic fine powder a-3.
[0170]
(Comparative Production Example 4 of Inorganic Fine Powder)
Table 1 shows the results of alkaline decomposition treatment from rare earth chloride obtained from monazite concentrate, followed by hydroxides of rare earth elements, acid treatment, drying, firing, and grinding / classification steps as shown in Table 1. Inorganic fine powder a-4 of Production Example 4 was obtained.
[0171]
(Production of inorganic fine powders B and C)
In a container, 1000 parts by mass of toluene and 200 parts by mass of silica were added and stirred with a mixer to form a slurry, 6 parts by mass of γ-aminopropyltriethoxysilane, dimethyl silicone oil (50 mm²/ S) 34 parts by mass was added, and the mixture was further stirred with a mixer. This slurry was subjected to a sand mill for 30 minutes using zirconia balls as media. The slurry was taken out from the sand mill, toluene was removed while reducing the pressure at 60 ° C., and then dried at 250 ° C. for 2 hours while stirring in a stainless steel container. Further, the mixture was crushed with a hammer mill to obtain inorganic fine powder i. In the same manner, inorganic fine powders ii and iii were obtained in the same manner as the inorganic fine powder i except that the matrix and the treating agent were as shown in Table 2.
[0172]
200 parts by mass of silica was placed in a closed type high-speed stirring mixer and purged with nitrogen. While stirring, 40 parts by mass of hexamethyldisilazane was sprayed. After the addition was completed, the mixture was stirred at room temperature for 10 minutes, and then heated to 300 ° C. while stirring at high speed and stirred for 1 hour. It returned to room temperature, stirring, and took out powder from the mixer, and obtained the inorganic fine powder iv.
[0173]
Table 2 shows the physical properties of the obtained inorganic fine powders i to iv.
[0174]
<Example 1>
・ Styrene-butyl acrylate copolymer (binder resin) 100 parts by mass
・ 90 parts by mass of magnetic iron oxide (magnetic material)
・ Triphenylmethane lake pigment (positive charge control agent) 2 parts by mass
・ Low molecular weight polyethylene (release agent) 4 parts by mass
The above materials were premixed with a Henschel mixer and then melt-kneaded with a twin-screw kneading extruder set at 130 ° C. The obtained kneaded product is cooled, coarsely pulverized with a canter mill, pulverized with a fine pulverizer using a jet stream, and the resulting finely pulverized powder is classified using a multi-division classifier utilizing the Coanda effect, Toner particles were obtained. A positively chargeable toner was obtained by externally adding 3.0 parts by weight of inorganic fine powder A-1 and 1.0 part by weight of inorganic fine powder i to 100 parts by weight of toner particles. The obtained positively chargeable toner had a weight average particle diameter of 7.2 μm.
[0175]
Using this toner, a copying test was conducted with a modified electrophotographic copying machine NP6085 (manufactured by Canon Inc.) having an amorphous silicon drum. Changes include bias to enable reversal development using positively chargeable toner, and others (non-image part drum potential 400V, image part drum potential 50V, development bias DC component 280V, image potential contrast 230V, drum surface (The temperature is set at 42 ° C.) and the cleaning method is a cleaning roller that is a magnet roller having eight poles with a magnetic flux density of 1000 gauss and a cleaning blade made of polyurethane rubber (hardness 70 degrees, thickness 3 mm). installed. At this time, the magnet roller was rotated in the forward direction at a peripheral speed of the photosensitive drum of 80%, the gap between the photosensitive drum and the magnet roller was 1.2 mm, and the amount of penetration of the cleaning blade into the photosensitive drum was 0.5 mm.
[0176]
In the copying test, 100,000 images were printed in an environment of a temperature of 23 ° C. and a humidity of 5% RH (room temperature and low humidity) and a temperature of 30 ° C. and a humidity of 80% RH (high temperature and high humidity). The following items were evaluated. The results are shown in Tables 3 and 4.
[0177]
1)Image density
The reflection density was measured using an SPI filter with a Macbeth densitometer (manufactured by Macbeth), and an image having a 5 mm diameter circle was measured.
[0178]
2)Fog
Using a reflection densitometer (reflectometer model TC6DS manufactured by Tokyo Denshoku Co., Ltd.), the worst value of the white background reflection density after image formation is Ds, the reflection average density of the transfer material before image formation is Dr, and Ds-Dr is The fog was evaluated as the fog amount. The smaller the number, the better the fog suppression.
[0179]
3)Toner adhesion on the surface of the photoconductor drum
Visual evaluation of photoreceptor surface and copy image after endurance of 100,000 sheets in normal temperature and low humidity environment (temperature 23 ° C, humidity 5% RH) and high temperature and high humidity environment (temperature 30 ° C, humidity 80% RH) did.
A: Not generated
B: Slightly generated, but no effect on the image.
C: Although there is sticking, the influence on the image is small.
D: There is much sticking and the influence on the image is great.
[0180]
4)Image flow
Image flow was evaluated using the 100,000th image in a normal temperature and low humidity environment (temperature 23 ° C, humidity 5% RH) and in a high temperature and high humidity environment (temperature 30 ° C, humidity 80% RH). It was.
A: Not generated
B: Very slight occurrence.
C: Slightly generated.
D: Occurred and the image blurring portion is wide.
[0181]
5)Cleaning slip
Visual evaluation of cleaning blade and copy image after endurance of 100,000 sheets in normal temperature and low humidity environment (temperature 23 ° C, humidity 5% RH) and high temperature and high humidity environment (temperature 30 ° C, humidity 80% RH) did.
A: Not generated
B: Aggregates accumulate on the cleaning blade, but no slipping occurs.
C: The toner passing through the cleaning blade has occurred, and the image has streaks.
[0182]
6)Toner leakage from the edge of the cleaning blade
Visual observation of the cleaning blade and photoreceptor surface after endurance of 100,000 sheets in a normal temperature and low humidity environment (temperature 23 ° C., humidity 5% RH) and a high temperature and high humidity environment (temperature 30 ° C., humidity 80% RH) Evaluation was performed.
A: No leakage occurred
B: Very little toner leaks from the blade end.
C: Toner leaks from the blade end, but no drum end fusion occurs.
D: Toner fusion to the drum end occurs.
[0183]
7)Drum scraping amount
The film thickness of the drum before and after the endurance of 100,000 sheets was measured, and the difference was taken as the scraping amount.
[0184]
In the table, the amount of chipping per 100,000 sheets was displayed in nm. In Example 6 which will be described later, the measurement was performed when 15,000 sheets were used, and the values were displayed in units of μm in the table.
[0185]
<Example 2>
A positively chargeable toner was produced and evaluated in the same manner as in Example 1 except that 2.0 parts by mass of the inorganic fine powder A-2 was used instead of the inorganic fine powder A-1. The results are shown in Tables 3 and 4.
[0186]
<Example 3>
A positively chargeable toner was produced and evaluated in the same manner as in Example 1 except that 1.0 part by mass of the inorganic fine powder A-3 was used instead of the inorganic fine powder A-1. The results are shown in Tables 3 and 4.
[0187]
<Example 4>
Instead of the inorganic fine powder A-1 and the inorganic fine powder i, 4.0 parts by mass of the inorganic fine powder A-4 and 0.8 parts by mass of the inorganic fine powder ii are used in the same manner as in Example 1. A positively charged toner was produced and evaluated. The results are shown in Tables 3 and 4.
[0188]
<Example 5>
Instead of the inorganic fine powder A-1 and the inorganic fine powder i, the same procedure as in Example 1 was performed except that 3.0 parts by mass of the inorganic fine powder A-5 and 0.8 parts by mass of the inorganic fine powder ii were used. A positively charged toner was produced and evaluated. The results are shown in Tables 3 and 4.
[0189]
<Example 6>
・ Styrene-butyl acrylate copolymer (resin) 100 parts by mass
・ 90 parts by mass of magnetic iron oxide (magnetic material)
・ Monoazo dye-based chromium complex (negative charge control agent) 2 parts by mass
・ Low molecular weight polypropylene (release agent) 4 parts by mass
The above materials were premixed with a Henschel mixer and then melt-kneaded with a twin-screw kneading extruder set at 130 ° C. The obtained kneaded product is cooled, coarsely pulverized with a canter mill, pulverized with a fine pulverizer using a jet stream, and the resulting finely pulverized powder is classified using a multi-division classifier utilizing the Coanda effect, Toner particles were obtained. A negatively chargeable toner was obtained by externally mixing 0.5 parts by mass of inorganic fine powder A-6 and 1.0 part by mass of inorganic fine powder iii with respect to 100 parts by mass of toner particles. The obtained negatively chargeable toner had a weight average particle diameter of 6.5 μm.
[0190]
The toner is a laser beam printer LBP-930 (manufactured by Canon Inc., using an OPC photosensitive drum), the non-image portion drum potential is -700 V, the image portion drum potential is -170 V, the developing bias DC component is -500 V, and the image potential. The contrast was set to 330 V, and a cleaning blade made of polyurethane rubber (hardness 65 degrees, thickness 1.2 mm, penetration amount 0.9 mm into the photoreceptor) was installed as a cleaner member. Under the above conditions, 15,000 sheets were printed and evaluated in the same manner as in Example 1. The results are shown in Tables 3 and 4.
[0191]
<Example 7>
-Cross-linked polyester resin (binder resin) 100 parts by mass
・ 90 parts by mass of magnetic iron oxide (magnetic material)
・ Monoazo dye-based chromium complex (negative charge control agent) 2 parts by mass
・ Low molecular weight polypropylene (release agent) 4 parts by mass
The above materials were premixed with a Henschel mixer and then melt-kneaded with a twin-screw kneading extruder set at 130 ° C. The obtained kneaded product is cooled, coarsely pulverized with a canter mill, pulverized with a fine pulverizer using a jet stream, and the resulting finely pulverized powder is classified using a multi-division classifier utilizing the Coanda effect, Toner particles were obtained. To 100 parts by mass of toner particles, 5.0 parts by mass of inorganic fine powder A-7 and 1.0 part by mass of inorganic fine powder iv were externally added to obtain a negatively chargeable toner. The obtained negatively chargeable toner had a weight average particle diameter of 7.8 μm.
[0192]
As for the toner, an electrophotographic copying machine NP6085 (manufactured by Canon Inc.) having a commercially available amorphous silicon drum is used. Non-image portion drum potential 50V, image portion drum potential 420V, development bias DC component 190V, image potential contrast 230V, drum surface temperature The temperature is set to 42 ° C, and as a cleaning method, a magnet roller having 6 poles with a magnetic flux density of 750 gauss and a cleaning blade made of polyurethane rubber (hardness 73 degrees, thickness 3 mm) are installed as a cleaning roller. did. At this time, the magnet roller was rotated in the forward direction at a peripheral speed of the photosensitive drum of 80%, the gap between the photosensitive drum and the magnet roller was 1.2 mm, and the amount of penetration of the cleaning blade into the photosensitive drum was set to 0.5 mm. Using this, evaluation was performed in the same manner as in Example 1. The results are shown in Tables 3 and 4.
[0193]
<Comparative Example 1>
A positively chargeable toner was produced and evaluated in the same manner as in Example 1 except that the inorganic fine powder a-1 was used instead of the inorganic fine powder A-1. The results are shown in Tables 3 and 4.
[0194]
<Comparative example 2>
A negatively chargeable toner was produced and evaluated in the same manner as in Example 7 except that the inorganic fine powder a-2 was used instead of the inorganic fine powder A-7. The results are shown in Tables 3 and 4.
[0195]
<Comparative Examples 3 and 4>
A positively chargeable toner was produced and evaluated in the same manner as in Example 1 except that the inorganic fine powders a-3 and a-4 were used instead of the inorganic fine powder A-1. The results are shown in Tables 3 and 4.
[0196]
<Example 8>
・ Styrene-butyl acrylate copolymer (binder resin) 100 parts by mass
-Copper phthalocyanine (colorant) 3.5 parts by mass
・ Triphenylmethane lake pigment (positive charge control agent) 2 parts by mass
・ Low molecular weight polyethylene (release agent) 3 parts by mass
The above materials were premixed with a Henschel mixer and then melt-kneaded with a biaxial kneading extruder set at 120 ° C. The obtained kneaded product is cooled and coarsely pulverized with a cutter mill, and then finely pulverized with a fine pulverizer using a jet stream. The obtained finely pulverized product is further classified with an air classifier, and toner particles are separated. Obtained. A positively chargeable non-magnetic toner was obtained by adding 1.0 part by mass of inorganic fine powder A-1 and 1.0 part by mass of inorganic fine powder i to 100 parts by mass of toner particles. The obtained toner had a weight average particle diameter of 8.5 μm.
[0197]
Using this toner, a commercially available copying machine FC-330 (using an OPC photosensitive drum manufactured by Canon Inc.), a non-image part drum potential -150 V, an image part drum potential -600 V, a developing bias DC component -280 V, an image potential. The contrast was set to 320 V, and a cleaning blade made of polyurethane rubber (having a hardness of 65 degrees, a thickness of 1.2 mm, and an intrusion amount of 0.7 mm) was installed as a cleaning member. Under the above conditions, a copy test of 1000 sheets was conducted in an environment of a temperature of 30 ° C. and a humidity of 80% RH (high temperature and high humidity) following an environment of a temperature of 23 ° C. and a humidity of 5% RH (normal temperature and low humidity). Thus, various evaluations (excluding drum scraping evaluation) were performed. The results are shown in Tables 3 and 4.
[0198]
[Table 1]

[0199]
[Table 2]

[0200]
[Table 3]

[0201]
[Table 4]

[0202]
【The invention's effect】
According to the toner and the image forming method of the present invention, image development, toner fusion, poor cleaning, etc. do not occur, and excellent developability and durability can be obtained even in an electrophotographic apparatus using an amorphous silicon photoreceptor, Further, stable charging characteristics can be obtained even when used as a positively charged toner.
[Brief description of the drawings]
FIG. 1 is a schematic explanatory view showing a specific example of an image forming apparatus for carrying out an image forming method of the present invention.
FIG. 2 is an enlarged explanatory view of a developing device.
FIG. 3 is a schematic explanatory view showing another specific example of the developing device.

Claims (35)

A toner having toner particles containing at least a binder resin and a colorant, and inorganic fine powder A;
The inorganic fine powder A contains 88.0 to 97.0% by mass of a rare earth element compound containing a rare earth element oxide,
The rare earth element compound contains 40.0 to 65.0% by mass of Ce in terms of oxide (CeO ₂ ), and La is 25.0 to 45. in terms of oxide (La ₂ O ₃ ). It is contained in an amount of 0% by mass, Nd is contained in an amount of 1.0 to 10.0% by mass in terms of oxide (in terms of Nd ₂ O ₃ ), and Pr in terms of oxide (in terms of Pr ₆ O ₁₁ ). 0 to 10.0% by mass,
The toner, wherein the rare earth element compound contains a rare earth fluoride compound, and the inorganic fine powder A has a fluorine element content of 2.0 to 11.0% by mass. The inorganic fine powder A has a volume average particle size of 0.1 to 4.0 µm and a BET specific surface area of 0.5 to 15.0 m ² / g as measured by a nitrogen gas adsorption method. 1. The toner according to 1. The inorganic fine powder A has a volume average particle size of 0.2 to 2.0 μm and a BET specific surface area of 1.0 to 10.0 m ² / g as measured by a nitrogen gas adsorption method. The toner according to 1. 4. The toner according to claim 1, wherein the inorganic fine powder A contains 89.0 to 96.0% by mass of a rare earth element compound. 4. The toner according to claim 1, wherein the inorganic fine powder A contains 90.0 to 95.0% by mass of a rare earth element compound. 6. The toner according to claim 1, wherein the toner contains 0.1 to 10.0% by mass of inorganic fine powder A. The toner according to claim 1, wherein the toner contains 0.1 to 7.0% by mass of inorganic fine powder A. The inorganic fine powder A is an inorganic fine powder obtained by treating a bastonite ore with a rare earth oxide and partially fluorinating with hydrofluoric acid. toner. 9. The toner according to claim 1, wherein the inorganic fine powder A has a uranium and thorium content of less than 100 ppm on a mass basis. The toner according to claim 1, wherein the toner contains an inorganic fine powder B having a pH of 7 or more. The toner according to claim 1, wherein the toner contains inorganic fine powder C treated with silicone oil. The toner according to claim 1, wherein the toner is positively charged. The toner according to claim 1, wherein the toner has a weight average particle diameter of 4 to 13 μm. The toner according to claim 1, wherein the toner has a weight average particle diameter of 5 to 12 μm. A charging step of charging the latent image carrier, an image forming step of forming an electrostatic image on the charged latent image carrier, a developing step of developing the electrostatic image with toner to form a toner image, A transfer step of transferring the toner image formed on the image carrier onto the recording material with or without the intermediate transfer member, a fixing step of heating and fixing the toner image on the recording material, and a latent image after the transfer. An image forming method having at least a cleaning step of cleaning the surface of the image carrier with a cleaning member,
The toner has toner particles containing at least a binder resin and a colorant, and inorganic fine powder A,
The inorganic fine powder A contains 88.0 to 97.0% by mass of a rare earth element compound containing a rare earth element oxide,
The rare earth element compound contains 40.0 to 65.0% by mass of Ce in terms of oxide (CeO ₂ ), and La is 25.0 to 45. in terms of oxide (La ₂ O ₃ ). It is contained in an amount of 0% by mass, Nd is contained in an amount of 1.0 to 10.0% by mass in terms of oxide (in terms of Nd ₂ O ₃ ), and Pr in terms of oxide (in terms of Pr ₆ O ₁₁ ). 0 to 10.0% by mass,
The image forming method, wherein the rare earth element compound contains a rare earth fluoride compound, and the fluorine element content of the inorganic fine powder A is 2.0 to 11.0% by mass. The image forming method according to claim 15, wherein the latent image carrier is an amorphous silicon photoconductor. 17. The image forming method according to claim 16, wherein the digital latent image is formed by charging the amorphous silicon photoconductor and exposing the charged amorphous silicon photoconductor. The amorphous silicon photoconductor is charged to a positive potential, a digital latent image is formed by exposure, and the digital latent image is developed by a reversal development method with a positively chargeable toner having a positive frictional charge. Item 17. The image forming method according to Item 16. The image forming method according to claim 15, wherein the surface temperature of the latent image carrier is adjusted to 45 ° C. or lower during image formation. The image forming method according to claim 15, wherein the cleaning step is performed by a cleaning blade, a cleaning roller, or a combination thereof. The image forming method according to claim 15, wherein the cleaning step is performed using at least a cleaning roller, and the cleaning roller includes magnetism generating means. The image forming method according to claim 15, wherein an elastic roller is used as a conveying unit that conveys the recording material to the transfer process. The inorganic fine powder A has a volume average particle size of 0.1 to 4.0 µm and a BET specific surface area of 0.5 to 15.0 m ² / g as measured by a nitrogen gas adsorption method. The image forming method according to any one of 15 to 22. The inorganic fine powder A has a volume average particle size of 0.2 to 2.0 μm and a BET specific surface area of 1.0 to 10.0 m ² / g as measured by a nitrogen gas adsorption method. The image forming method according to any one of 15 to 22. 25. The image forming method according to any one of claims 15 to 24, wherein the inorganic fine powder A contains 89.0 to 96.0% by mass of a rare earth element compound. The image forming method according to any one of claims 15 to 24, wherein the inorganic fine powder A contains 90.0 to 95.0 mass% of a rare earth element compound. 27. The image forming method according to claim 15, wherein the toner contains 0.1 to 10.0% by mass of inorganic fine powder A. 27. The image forming method according to any one of claims 15 to 26, wherein the toner contains 0.1 to 7.0% by mass of inorganic fine powder A. 29. The inorganic fine powder A according to any one of claims 15 to 28, wherein the inorganic fine powder A is an inorganic fine powder obtained by treating a basnetite ore with a rare earth oxide and partially fluorinating with hydrofluoric acid. Image forming method. 30. The image forming method according to claim 15, wherein the contents of uranium and thorium in the inorganic fine powder A are both less than 100 ppm on a mass basis. 31. The image forming method according to claim 15, wherein the toner contains inorganic fine powder B having a pH of 7 or more. 31. The image forming method according to claim 15, wherein the toner contains an inorganic fine powder C treated with silicone oil. The image forming method according to claim 15, wherein the toner is positively charged. The image forming method according to claim 15, wherein the toner has a weight average particle diameter of 4 to 13 μm. The image forming method according to claim 15, wherein the toner has a weight average particle diameter of 5 to 12 μm.

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