JP3576799B2 - Toner for developing electrostatic image and method for producing toner - Google Patents

Description

〔式中、Ｒ _１ 及びＲ _３ は、水素原子、Ｃ _１ 〜 _１８ のアルキル基、Ｃ _２ 〜 _１８ のアルケニル基、スルホンアミド基、メシル基、スルホン酸基、ヒドロキシ基、Ｃ _１ 〜 _１８ のアルコキシ基、アセチルアミノ基、ベンゾイルアミノ基、ハロゲン原子及び
【００２０】
【外６】

で表される官能基からなるグループより選ばれる原子又は官能基であり、Ｒ _１ とＲ _３ とは同じであっても異なっていても良く、ｎ及びｎ′は１〜３の整数を示し、Ｒ _５ は、Ｃ _１ 〜 _１８ のアルキル基又はＣ _６ 〜 _１８ のアリール基を表し、
Ｒ _２ 及びＲ _４ は、水素原子又は、ニトロ基を示し、Ｒ _２ とＲ _４ とは同じであっても異なっていても良く、
Ｘ _１ 及びＸ _２ は、水素原子、Ｃ _１ 〜 _５ のアルキル基、Ｃ _１ 〜 _５ のアルコキシ基、ニトロ基及びハロゲン原子からなるグループより選ばれる原子又は官能基を表し、Ｘ _１ とＸ _２ とは同じであっても異なっていても良く、ｍ及びｍ′は１〜３の整数を示し、
Ａ ^＋ は、水素イオン、ナトリウムイオン、カリウムイオン、アンモニウムイオンからなるグループより選ばれるイオン又はそれらの混合物を示す。〕
【００２２】
本発明は、少なくとも下記工程、
ｉ）重合性単量体、カーボンブラック、式（２）で表されるアゾ系鉄化合物及びオキシカルボン酸金属化合物を含有する重合性単量体組成物を調製する工程、
ｉｉ）該重合性単量体組成物を水系媒体中へ分散して重合性単量体組成物の粒子を生成する工程、
ｉｉｉ）該粒子中の重合性単量体を重合を有してトナー粒子を生成する工程、
を有することを特徴とするトナー粒子を有する静電荷像現像用トナーの製造方法に関する。
【００２３】
【外７】

〔式中、Ｒ _１ 及びＲ _３ は、水素原子、Ｃ _１ 〜 _１８ のアルキル基、Ｃ _２ 〜 _１８ のアルケニル基、スルホンアミド基、メシル基、スルホン酸基、ヒドロキシ基、Ｃ _１ 〜 _１８ のアルコキシ基、アセチルアミノ基、ベンゾイルアミノ基、ハロゲン原子及び
【００２４】
【外８】

で表される官能基からなるグループより選ばれる原子又は官能基であり、Ｒ _１ とＲ _３ とは同じであっても異なっていても良く、ｎ及びｎ′は１〜３の整数を示し、Ｒ _５ は、Ｃ _１ 〜 _１８ のアルキル基又はＣ _６ 〜 _１８ のアリール基を表し、
Ｒ _２ 及びＲ _４ は、水素原子又は、ニトロ基を示し、Ｒ _２ とＲ _４ とは同じであっても異なっていても良く、
Ｘ _１ 及びＸ _２ は、水素原子、Ｃ _１ 〜 _５ のアルキル基、Ｃ _１ 〜 _５ のアルコキシ基、ニトロ基及びハロゲン原子からなるグループより選ばれる原子又は官能基を表し、Ｘ _１ とＸ _２ とは同じであっても異なっていても良く、ｍ及びｍ′は１〜３の整数を示し、
Ａ ^＋ は、水素イオン、ナトリウムイオン、カリウムイオン、アンモニウムイオンからなるグループより選ばれるイオン又はそれらの混合物を示す。〕
【００２６】
【発明の実施の形態】
前述したように、形状が球形で平滑な表面を持っているトナーは、帯電部材との接触点が小さいため、高湿下では帯電性が低下し、トナー飛散やカブリが発生しやすかった。これを解決するために、帯電量を増大させると、今度は低湿下で帯電量が過大となり、得られる画像の濃度の低下、転写効率の悪化等が発生した。
【００２７】
この課題に対して、本発明者らは、特定のアゾ系鉄化合物と、オキシカルボン酸金属化合物を併用することで解決したのである。
【００２８】
一般に電荷制御剤として用いられる有機酸の金属化合物を用いた現像剤は、比較的高い帯電性を示す場合があるものの、高湿下では帯電量の低下が見られ、低湿下においては帯電速度の低下が見られる。
【００２９】
この原因としては金属付近での水分の吸脱着が考えられ、高湿下では金属化合物への吸着水量が増大するため帯電量が低下し、低湿下では金属化合物中の吸着水が減少するため抵抗が高くなり帯電速度が低下するものと考えられる。
【００３０】
これに対して、有機酸の中でもオキシカルボン酸のようにカルボキシル基酸素上の負電荷密度が低いと思われるものを使用した場合、高湿下においても高い帯電量を得ることができる。これに関しては、カルボキシル基酸素上の負電荷密度が小さい場合、金属と結合しても金属原子上の電子密度があまり上昇せず、金属化合物の負帯電能力が高いものと考えられる。
【００３１】
特に芳香族オキシカルボン酸においては高い効果が見い出された。この理由については明らかではないが、芳香族オキシカルボン酸は共鳴構造により、カルボキシル酸素上の負電荷密度がより小さいこと及び立体的に大きい構造を有するために、結合した金属分子に対して水分子をブロックしやすいことなどが考えられる。
【００３２】
なお、オキシカルボン酸金属化合物を含有する現像剤に関しては、これまでいくつか公開されている。例えば、特公昭５５−４２７５２号公報においてサリチル酸クロム化合物が、特開昭６３−２０７４号公報及び特開昭６３−３３７５５号公報においてはサリチル酸亜鉛化合物が、また特開昭６３−２０８８６５号公報、特開昭６３−２３７０６５号公報及び特開昭６４−１０２６１号公報にはサリチル酸のアルミニウム化合物が開示されている。
【００３３】
しかしながら、本発明者らの検討では、オキシカルボン酸金属化合物のみでは、本発明のような球形で表面が平滑なトナーにおいて、低湿下での帯電速度が遅く、初期と耐久時の帯電特性の差が大きく、画像濃度の低下等を招いた。
【００３４】
そこで、本発明者らは、一般式（１）に示されるアゾ系鉄化合物を併用すると、低湿下での帯電速度の低下を防止できると共に、高湿下での帯電もさらに良好にできることを見い出したのである。
【００３５】
このアゾ系鉄化合物は、単独で荷電制御剤として使用すると、帯電速度は良好で、帯電量の立ち上がりは解決できるものの、帯電量の絶対値が低く、高湿下での飛散やカブリが問題であった。
【００３６】
しかるに、本発明者らの検討によると、特定のアゾ系鉄化合物とオキシカルボン酸金属化合物を併用すると、各化合物の性能を加算したよりも大きな効果が得られ、各環境下での帯電性を大幅に改善することを見い出したのである。
【００３７】
その理由は明らかではないが、併用することによりお互いのトナー中での分散性が向上し、より有効な性能が得られるため、環境特性が良好になると考えられる。
【００３８】
本発明の構成は、重合法により形成されたトナーにおいて効果が大きく、特に高湿下での帯電特性を大幅に向上することが可能となった。
【００３９】
その理由は明らかではないが、本発明のアゾ系鉄化合物により、通常使用される顔料であるカーボンブラックの分散性が著しく向上する。そのため、導電性のカーボンブラックによる導電経路の形成が少なく、また、トナー表面に存在するカーボンブラックも少ないため、負電荷のリークが押さえられ、帯電量が増大する。
【００４０】
さらに、本発明者らの検討では、該アゾ系鉄化合物とオキシカルボン酸金属化合物の添加量が、該アゾ系鉄化合物の添加量をＡ重量部、オキシカルボン酸金属化合物の添加量をＢ重量部とすると、
０．１≦Ａ／Ｂ≦２０
であることが好ましい。その理由は明らかではないが、トナー中の各化合物の分散状態が変化し、前述のような相乗効果が得られないためと考えれらる。０．１未満や２０を超えた場合は、低湿下での帯電の立ち上がりの悪化および高湿下での帯電量の低下が生じる。
【００４１】
本発明で使用するアゾ系鉄化合物は、下記式（２）で示す構造を有している。
【００４６】
【外２０】

〔式中、Ｒ_１ 及びＲ_３ は、水素原子、Ｃ_１ 〜_１８のアルキル基、Ｃ_２ 〜_１８のアルケニル基、スルホンアミド基、メシル基、スルホン酸基、ヒドロキシ基、Ｃ_１ 〜_１８のアルコキシ基、アセチルアミノ基、ベンゾイルアミノ基、ハロゲン原子及び
【００４７】
【外２１】

で表される官能基からなるグループより選ばれる原子又は官能基であり、Ｒ_１ とＲ_３ とは同じであっても異なっていても良く、ｎ及びｎ′は１〜３の整数を示し、Ｒ_５ は、Ｃ_１ 〜_１８のアルキル基又はＣ_６ 〜_１８のアリール基を表し、Ｒ_２ 及びＲ_４ は、水素原子又は、ニトロ基を示し、Ｒ_２ とＲ_４ とは同じであっても異なっていても良く、Ｘ_１ 及びＸ_２ は、水素原子、Ｃ_１ 〜_５ のアルキル基、Ｃ_１ 〜_５ のアルコキシ基、ニトロ基及びハロゲン原子からなるグループより選ばれる原子又は官能基を表し、Ｘ_１ とＸ_２ とは同じであっても異なっていても良く、ｍ及びｍ′は１〜３の整数を示し、Ａ^＋ は、水素イオン、ナトリウムイオン、カリウムイオン、アンモニウムイオンからなるグループより選ばれるイオン又はそれらの混合物を表す。〕
【００４８】
前記一般式のアゾ系鉄化合物の代表的な具体例としては、次のような化合物が挙げられる。
【００４９】
【外２２】

【００５０】
【外９】

【００５１】
本発明に用いることのできるアゾ系鉄化合物は、一般に、ジアゾ化置換アミノフェノールと置換ナフトールとをカップリング反応させ、その後得られた生成物を硫化鉄のような鉄塩と結合させることにより調製できる。
【００５２】
また、該アゾ系鉄化合物は結着樹脂１００重量部に対して０．１〜８重量部好ましくは０．１〜６重量部用いられる。０．１重量部未満では前述の効果が小さく、８重量部を超えてしまうと、帯電部材等への汚染等が発生する。
【００５３】
次に、本発明において用いられるオキシカルボン酸金属化合物において、使用されるオキシカルボン酸としては、リンゴ酸、ジメチロールブタン酸、酒石酸、クエン酸、サリチル酸、ヒドロキシナフトエ酸等がある。中でも炭素数５以下のアルキル基を持つアルキルサリチル酸、ジアルキルサリチル酸が好ましく、３，５−ジアルキルサリチル酸が特に好ましい。アルキル基としてはｔ−ブチル基が最も好ましく用いられる。
【００５４】
また、別の化合物としては、２−ヒドロキシ−３−ナフトエ酸、炭素数５以下のアルキル−２−ヒドロキシ−３−ナフトエ酸、５，６，７，８−テトラハロゲン−２−ヒドロキシ−３−ナフトエ酸などが用いられる。
【００５５】
一方、使用される金属原子としてはアルミニウム、亜鉛、クロム、コバルト、ニッケル、銅、鉄、ジルコニア等が挙げられるが、本発明者らの検討においては、アルミニウム及び亜鉛の化合物が、前記アゾ系鉄化合物と併用した場合効果が大であり、特に好ましい。
【００５６】
好ましいオキシカルボン酸金属化合物としては、以下の化合物が例示される。
【００５７】
【外２４】

〔式中、Ａは水素、アルカリ金属又はアルカリ土類金属を示す。〕
【００５８】
【外２５】

【００５９】
【外２６】

【００６０】
【外２７】

【００６１】
また、本発明によるオキシカルボン酸金属化合物の添加量は、結着樹脂１００重量部に対して０．１〜１０重量部好ましくは１〜６重量部である。０．１重量部未満では前述の効果が小さく、１０重量部を超えてしまうと、前記アゾ系鉄化合物同様に帯電部材等への汚染等が発生する。
【００６２】
本発明トナーにおいては、トナーの形状係数を示すＳＦ−１が１００〜１４０、ＳＦ−２が１００〜１２０であることが好ましい。本発明に用いられる形状係数を示すＳＦ−１、ＳＦ−２とは、日立製作所製ＦＥ−ＳＥＭ（Ｓ−８００）を用いトナー像を１００個無作為にサンプリングし、その画像情報はインターフェースを介してニコレ社製画像解析装置（Ｌｕｚｅｘ３）に導入し解析を行い下式より算出し得られた値を、本発明においては形状係数ＳＦ−１，ＳＦ−２と定義した。
【００６３】
ＳＦ−１＝｛（ＭＸＬＮＧ）^２ ／ＡＲＥＡ｝×（π／４）×１００
ＳＦ−２＝｛（ＰＥＲＩ）^２ ／ＡＲＥＡ｝×（１／４π）×１００
（式中、ＡＲＥＡ＝トナー投影面積、ＭＸＬＮＧ＝絶対最大長、ＰＥＲＩ＝トナー像の周長である）
【００６４】
即ち、トナーの形状係数ＳＦ−１は球形度合を示し、１４０より大きいと、球形から外れて不定形に近くなる。ＳＦ−２は凹凸度合いを示し、１２０より大きいとトナー表面の凹凸が顕著となる。
【００６５】
上記のようにトナーの形状係数を小さく制御することによる利点を以下に説明する。第一に、感光体ドラムとの接触面積が小さくなるため、付着力が低下し、高い効率で転写することが可能となる。
【００６６】
図１に転写効率と形状係数の相関関係を示す。この図から、形状係数が小さいほど転写効率が上がることがわかる。その結果クリーニング機中に回収される転写残存トナーが極めて少なくなり、クリーニング装置の小型化が可能となる。
【００６７】
第二の効果として、球形、平滑な、表面の均一であるトナーを用いることで、転写材に転写した後のトナーの帯電が一定であり、次の画像形成部に進んだ時点で、前回転写したトナーが今回の画像形成部で静電的に感光ドラムに剥ぎ取られる、再転写の現象を防ぐことができる。その結果転写材上のトナーが乱されることがなく、高画質の画像が得られる。
【００６８】
第三に小径の感光ドラムを使用することができる。すなわち、形状係数を球形に、かつ表面を平滑にすることにより、感光体ドラムとクリーナー部材との摩擦力を落とすことができ、感光体ドラムの摩耗を防止することが可能となる。
【００６９】
図２に、形状係数と潤滑性の相関関係を示す。なお、測定は硝子上にトナーを塗布し、その上に３００ｇの重りを乗せたウレタンゴムを乗せ、横方向から引いたときに動きだす荷重を測定した。この図から、形状係数が小さいほど潤滑性が高いことが明らかである。実際に装置上で試験を行っても、感光体ドラムの摩耗は極めて少なく、高寿命化を達成することができた。
【００７０】
しかし、上記に効果を得るために、形状係数を球形に、かつ表面を平滑にすると、前述のように不定形トナーに比較してトナー表面と帯電部材との接触点が小さく、帯電的には不利となり、例えば高湿下でのトナー飛散やカブリ等が問題となった。
【００７１】
しかるに、本発明の構成のトナーを採用することにより、良好な帯電性を確保しながら、高転写効率、再転写防止、小径ドラムの採用を達成することができたのである。
【００７２】
本発明のトナーの形状を上記の範囲にするためには、以下の方法が挙げられる。
【００７３】
特公昭３６−１０２３１号公報、特開昭５９−５３８５６号公報、特開昭５９−６１８４２号公報に述べられている懸濁重合方法を用いて直接トナーを生成する方法や、単量体には可溶で得られる重合体が不溶な水系有機溶剤を用い直接トナーを生成する分散重合方法又は水溶性極性重合開始剤存在下で直接重合しトナーを生成するソープフリー重合方法に代表される乳化重合方法等を用いトナーを製造することが可能である。
【００７４】
本発明においては、トナーの形状係数ＳＦ−１を１００〜１４０、ＳＦ−２を１００〜１２０に容易にコントロールでき、比較的容易に粒度分布がシャープで３〜１０μｍ粒径の微粒子トナーが得られる常圧下での、または加圧下での懸濁重合方法が特に好ましい。トナーの粒度分布制御や粒径の制御は、難水溶性の無機塩や保護コロイド作用をする分散剤の種類や添加量を変える方法や機械的装置条件例えばローターの周速・バス回数・攪拌羽根形状等の攪拌条件や容器形状又は、水溶液中での固形分濃度等を制御することにより所定の本発明のトナーを得ることができる。
【００７５】
本発明のトナーに用いられる樹脂としては、一般的に用いられているスチレン重合体スチレン−アクリル共重合体、スチレン−メタクリル共重合体等を利用することができる。
【００７６】
重合法による直接トナーを得る方法においては、それらの単量体が好ましく用いられる。具体的には、スチレン，ｏ（ｍ−，ｐ−）−メチルスチレン，ｍ（ｐ−）−エチルスチレン等のスチレン系単量体；（メタ）アクリル酸メチル，（メタ）アクリル酸エチル，（メタ）アクリル酸プロピル，（メタ）アクリル酸ブチル，（メタ）アクリル酸オクチル，（メタ）アクリル酸ドデシル，（メタ）アクリル酸ステアリル，（メタ）アクリル酸ベヘニル，（メタ）アクリル酸２−エチルヘキシル，（メタ）アクリル酸ジメチルアミノエチル，（メタ）アクリル酸ジエチルアミノエチル等の（メタ）アクリル酸エステル系単量体；ブタジエン，イソプレン，シクロヘキセン，（メタ）アクリロニトリル，アクリル酸アミド等の単量体が好ましく用いられる。これらは、単独または一般的には出版物ポリマーハンドブック第２版ＩＩＩ−Ｐ１３９〜１９２（Ｊｏｈｎ Ｗｉｌｅｙ＆Ｓｏｎｓ社製）に記載の理論ガラス温度（Ｔｇ）が、４０〜７５℃を示すように単量体を適宜混合し用いられる。理論ガラス転移温度が４０℃未満の場合には、トナーの保存安定性や現像剤の耐久安定性の面から問題が生じ、一方７５℃を超える場合は定着点の上昇をもたらし、特にフルカラートナーの場合においては各色トナーの混色が不十分となり色再現性に乏しく、更にＯＨＰ画像の透明性を著しく低下させ高画質の面から好ましくない。
【００７７】
結着樹脂の分子量は、ＧＰＣ（ゲルパーミエーションクロマトグラフィー）により測定される。具体的なＧＰＣの測定方法としては、予めトナーをソックスレー抽出器を用いトルエン溶剤で２０時間抽出を行った後、ロータリーエバポレータでトルエンを留去せしめ、更にエステル系ワックスは溶解するが結着樹脂は溶解し得ない有機溶剤例えばクロロホルム等を加え十分洗浄を行った後、ＴＨＦ（テトラヒドロフラン）に可溶した溶液をポア径が０．３μｍの耐溶剤性メンブランフィルターでろ過したサンプルをウォーターズ社製１５０Ｃを用い、カラム構成は昭和電工製Ａ−８０１、８０２、８０３、８０４、８０５、８０６、８０７を連結し標準ポリスチレン樹脂の検量線を用い分子量分布を測定し得る。得られた樹脂成分の数平均分子量（Ｍｎ）は、５０００〜１，０００，０００であり、重量平均分子量（Ｍｗ）と数平均分子量（Ｍｎ）の比（Ｍｗ／Ｍｎ）は、２〜１００を示す結着樹脂が本発明には好ましい。
【００７８】
また、本発明での重合法トナーの単量体系には、極性基を有する重合体、共重合体を添加しても良い。
【００７９】
本発明に使用できる極性重合体、極性共重合体を以下に例示する。
【００８０】
メタクリル酸ジメチルアミノエチル、メタクリル酸ジエチルアミノエチルなど含窒素単量体の重合体もしくはスチレン−不飽和カルボン酸エステル等の共重合体、アクリロニトリル等のニトリル系単量体、塩化ビニル等の含ハロゲン系単量体、アクリル酸、メタクリル酸の不飽和カルボン酸、その他不飽和二塩基酸、不飽和二塩基酸無水物、ニトロ系単量体等の重合体もしくはスチレン系単量体等との共重合体、ポリエステル、ポリカーボネート、エポキシ樹脂等が挙げられる。
【００８１】
本発明においては、着色剤としてカーボンブラックが用いられる。中でも、平均一次粒径１０〜７０ｎｍ、窒素吸着による比表面積が１００ｍ^２ ／ｇ以下、揮発分が２％以下、ｐＨが２以下、ＤＢＰ吸油量が５０〜２００ｍｌ／１００ｇのカーボンブラックが好ましく用いられる。またカーボンブラックの添加量は、結着樹脂に１００重量部に対して１〜２０重量部用いられる。
【００８２】
カーボンブラックの平均一次粒径は１０〜７０ｎｍのものが好ましく、より好ましくは２０〜６０ｎｍ、更に好ましくは２５〜４５ｎｍのものである。カーボンブラックの一次粒径が１０ｎｍ未満であると本発明において用いられる特定のアゾ系鉄化合物と併用した場合、粘度が大きくなりすぎ、使いこなすのが困難であり、さらに、平均一次粒径が非常に微細なため、十分な分散性が得られにくい。さらに、カーボンブラックの平均一次粒径が７０ｎｍより大きい場合は、良好に分散してもトナーの着色力が低くなりすぎ、着色力をあげるために、多量に使用すると、トナーの帯電が低下してしまい使用に適さない。
【００８３】
カーボンブラックのｐＨは２以上が好ましく、更に好ましくは４以上である。ｐＨが２より低い場合には、カーボンブラックの表面に官能基が多く存在しており、重合阻害を引き起こし易い。
【００８４】
また、カーボンブラックの窒素吸着による比表面積は、１００ｍ^２ ／ｇ以下であることが好ましく、より好ましくは３０〜９０ｍ^２ ／ｇ、更に好ましくは４０〜９０ｍ^２ ／ｇである。又、カーボンブラックの揮発分は、２％以下であることが好ましく、より好ましくは０．１〜１．８％、更に好ましくは０．１〜１．７％である。比表面積が１００ｍ^２ ／ｇを超えると、重合阻害が生じやすくなり、揮発分が２％を超える場合にはカーボンブラック表面に重合阻害基が多数存在するため使用に適さない。
【００８５】
カーボンブラックのＤＢＰ吸油量は、５０〜２００ｍｌ／１００ｇであることが好ましく、より好ましくは１１０〜２００ｍｌ／１００ｇ、更に好ましくは１２０〜１６０ｍｌ／１００ｇである。ＤＢＰ吸油量が、５０ｍｌ／１００ｇ未満であると、トナー粒子中でのカーボンブラックの分散性が充分ではなく、着色性が低下しやすい。また２００ｍｌ／１００ｇを超えると、トナー表面の導電性が高くなりすぎ、特に高湿化での帯電が低下してしまい好ましくない。
【００８６】
カーボンブラックの添加量は、結着樹脂に１００重量部に対して１〜２０重量部用いられるが、分散性の面よりアゾ系鉄化合物の添加量との間において以下の関係を満たすことが好ましい。アゾ系鉄化合物の添加量をＡ重量部、カーボンブラックの添加量をＣ重量部とすると、
３≦Ｃ／Ａ≦５０
を満たすことが好ましく、さらに好ましくは下記関係
３≦Ｃ／Ａ≦３８
を満たす。
【００８７】
カーボンブラックに対してアゾ系鉄化合物が少なすぎると、粘度が上がらず、カーボンブラックが安定して分散され難い。この場合、時間の経過とともにカーボンブラックが沈殿し、この分散液を使用してトナーを作製すると充分な着色力が得られ難い。
【００８８】
カーボンブラックに対してアゾ系鉄化合物が多すぎると、アゾ系鉄化合物が二次凝集を起こし易く、分散性が低下するとともに、この二次凝集体が重合阻害を起こし易く、トナー粒子として取り出すのが困難となる。
【００８９】
次に、カーボンブラックの各物性の測定方法について説明する。
【００９０】
（１）カーボンブラックのＤＢＰ吸油量
ＪＩＳ Ｋ ６２２１に記載されたＡ法に準じて、ＤＢＰを乾燥試料（カーボンブラック）に滴下することによりＤＢＰ吸油量を求める。
【００９１】
（２）カーボンブラックの窒素吸着による比表面積の測定
ＡＳＴＭ Ｄ ３０３７に準じて測定を行う。
【００９２】
（３）カーボンブラックの揮発分の測定
ＪＩＳ Ｋ ６２２１に準じて、乾燥試料の加熱前及び加熱後の質量を測定することにより、揮発分を求める。
【００９３】
（４）カーボンブラックの平均一次粒径の測定
透過型電子顕微鏡を用いＡＳＴＭ Ｄ３８４９−８９に準じて測定する。
【００９４】
（５）カーボンブラックのｐＨの測定
ＪＩＳ Ｋ ６２２１に準じて、試料に水を加え、煮沸後、上澄み液を除去し、試料のｐＨを測定する。
【００９５】
本発明のトナーは、カーボンブラックを含有する黒色トナーであるが、イエロートナー、マゼンタトナー、シアントナーと併用し、フルカラー画像を形成することも可能である。
【００９６】
又本発明のトナーは、磁性体を含有する磁性トナーとしても用いることができる。磁性トナーとする場合には、結着樹脂１００重量部に対し、４０〜１５０重量部添加される。
【００９７】
直接重合方法によりトナー粒子を製造する際には、重合開始剤として、例えば、２，２′−アゾビス−（２，４−ジメチルバレロニトリル）、２，２′−アゾビスイソブチロニトリル、１，１′−アゾビス（シクロヘキサン−１−カルボニトリル）、２，２′−アゾビス−４−メトキシ−２，４−ジメチルバレロニトリル、アゾビスイソブチロニトリル等のアゾ系又はジアゾ系重合開始剤；ベンゾイルペルオキシド、メチルエチルケトンペルオキシド、ジイソプロピルペルオキシカーボネート、クメンヒドロペルオキシド、２，４−ジクロロベンゾイルペルオキシド、ラウロイルペルオキシド等の過酸化物系重合開始剤が用いられる。
【００９８】
該重合開始剤の添加量は、目的とする重合度により変化するが一般的には単量体に対し０．５〜２０重量％添加され用いられる。重合開始剤の種類は、重合方法により若干異なるが、十時間半減期温度を参考に、単独又は混合し利用される。
【００９９】
重合度を制御するため公知の架橋剤，連鎖移動剤，重合禁止剤等を更に添加し用いることも可能である。
【０１００】
本発明のトナー製造方法として懸濁重合を利用する場合には、用いる分散剤として例えば無機系酸化物として、リン酸三カルシウム，リン酸マグネシウム，リン酸アルミニウム、リン酸亜鉛，炭酸カルシウム，炭酸マグネシウム，水酸化カルシウム，水酸化マグネシウム，水酸化アルミニウム，メタケイ酸カルシウム，硫酸カルシウム，硫酸バリウム，ベントナイト，シリカ，アルミナ，磁性体，フェライト等が挙げられる。有機系化合物としては例えばポリビニルアルコール，ゼラチン，メチルセルロース，メチルヒドロキシプロピルセルロース，エチルセルロース，カルボキシメチルセルロースのナトリウム塩，デンプン等が水相に分散させて使用される。これら分散剤は、重合性単量体１００重量部に対して０．２〜１０重量部を使用することが好ましい。
【０１０１】
これら分散剤は、市販のものをそのまま用いても良いが、細かい均一な粒度を有する分散粒子を得るために、分散媒中にて高速撹拌下にて該無機化合物を生成させることも出来る。例えば、リン酸三カルシウムの場合、高速撹拌下において、リン酸ナトリウム水溶液と塩化カルシウム水溶液を混合することで懸濁重合方法に好ましい分散剤を得ることが出来る。また、これら分散剤の微細化のため０．００１〜０．１重量部の界面活性剤を併用しても良い。具体的には市販のノニオン，アニオン，カチオン型の界面活性剤が利用でき、例えばドデシル硫酸ナトリウム，テトラデシル硫酸ナトリウム，ペンタデシル硫酸ナトリウム，オクチル硫酸ナトリウム，オレイン酸ナトリウム，ラウリル酸ナトリウム，ステアリン酸カリウム，オレイン酸カルシウム等が好ましく用いられる。
【０１０２】
本発明は、直接重合方法を用いる場合においては、以下の如き製造方法によって具体的にトナーを製造することが可能である。単量体中にカーボンブラック，荷電制御剤，重合開始剤，その他の添加剤を加え、ホモジナイザー・超音波分散機等によって均一に溶解又は分散せしめた単量体組成物を、分散安定剤を含有する水相中に通常の撹拌機またはホモミキサー，ホモジナイザー等により分散せしめる。好ましくは単量体組成物からなる液滴が所望のトナー粒子のサイズを有するように撹拌速度・時間を調整し、造粒する。その後は分散安定剤の作用により、粒子状態が維持され、且つ粒子の沈降が防止される程度の撹拌を行えば良い。重合温度は４０℃以上、一般には５０〜９０℃の温度に設定して重合を行う。また、重合反応後半に昇温しても良く、更に、本発明のトナーを用いた画像形成方法における耐久性向上の目的で、未反応の重合性単量体，副生成物等を除去するために反応後半、又は、反応終了後に一部水系媒体を留去しても良い。反応終了後、生成したトナー粒子を洗浄・ろ過により回収し、乾燥する。懸濁重合法においては、通常単量体系１００重量部に対して水３００〜３０００重量部を分散媒として使用するのが好ましい。
【０１０３】
本発明において、カーボンブラックをより均一に分散させるために、以下のようなマスターバッチ工程を用いることにより好ましい方法である。
【０１０４】
重合性単量体中にカーボンブラック、荷電制御剤、重合開始剤、その他の添加剤を加えて、溶解及び分散をする前に、重合性単量体の一部に、カーボンブラック及びアゾ系鉄化合物のみを混合する。こうすることにより、重合性単量体に対してカーボンブラックを非常に高濃度にして混合できるため、分散液の濃度が高まり、混合時のシェアが十分にかかることから、アゾ系鉄化合物による分散効果との組み合わせで、カーボンブラックの分散性を飛躍的に向上させることができる。
【０１０５】
本発明において、トナーは、３．０乃至１０．０μｍ、好ましくは３．０乃至８．０μｍの重量平均粒径（Ｄ４）を有することが好ましい。
【０１０６】
トナーの体積平均粒径が１０．０μｍ以下の場合にはハイライト再現性がより良好になり、また３．０μｍ以上の場合には特に低湿環境下においてチャージアップしにくく、画像濃度の低下が生じ難くなる。
【０１０７】
本発明のトナーの粒度分布の測定はコールターカウンターＴＡ−ＩＩ型あるいはコールターマルチサイザー（コールター社製）を用いる。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、前記電界水溶液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分間分散処理を行な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、２μｍ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。
【０１０８】
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）及び体積平均粒径（Ｄｖ）（それぞれ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。
【０１０９】
本発明に用いられる現像方法は、一成分現像、二成分現像のどちらも対応できる。二成分磁気ブラシ現像方法を用いる場合は、そのキャリアとして、フェライト、マグネタイト、鉄粉あるいは、それらをアクリル樹脂、シリコーン樹脂、フッ素樹脂等でコーティングしたものが用いられる。一成分現像剤としては、磁性トナー、非磁性トナーのどちらを用いてもよい。
【０１１０】
【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。なお、以下の配合における部数は、特に説明のない場合は重量部である。
【０１１１】
（アルミニウム化合物製造例１）
ＮａＯＨ０．２５ｍｏｌ／ｌの水溶液１ｌにジ−ｔｅｒｔ−ブチルサリチル酸０．２モルを混合し、加熱溶解した。この溶液をＡｌ_２ （ＳＯ_４ ）_３ ０．０５ｍｏｌ／ｌの水溶液１ｌに添加し加熱撹拌した後、中性から弱アルカリ付近の条件下で濾別採取した。採取した白色沈殿物を、洗浄水が中性となるまで、水洗した後乾燥し目的生成物であるジ−ｔｅｒｔ−ブチルサリチル酸アルミニウム化合物を得た。
【０１１２】
また、その生成物のＦＤマススペクトルを分析した結果、主成分はオキシカルボン酸とアルミニウムの組成比が３：２で結合した化合物であることが確認された。
【０１１３】
（アルミニウム化合物製造例２）
ジ−ｔｅｒｔ−ブチルサリチルの代わりに２−ヒドロキシナフタレン−３−カルボン酸を用いる以外はアルミニウム化合物製造例１と同様の合成法で、ほぼ純度１００％の２−ヒドロキシナフタレン−３−カルボン酸アルミニウム化合物を得た。
【０１１４】
（亜鉛化合物製造例１）
Ａｌ_２ （ＳＯ_４ ）_３ の代わりにＺｎＳＯ_４ 水溶液を用いる以外はアルミニウム化合物製造例１と同様の合成法で、ジ−ｔｅｒｔ−ブチルサリチル酸亜鉛化合物を得た。
【０１１５】
〔重合トナーの製造例Ａ〕
イオン交換水７１０重量部に、０．１Ｍ−Ｎａ_３ ＰＯ_４ 水溶液４５０重量部を投入し、６０℃に加温した後、ＴＫ式ホモミキサー（特殊機化工業製）を用いて、１２０００ｒｐｍにて撹拌した。これに１．０Ｍ−ＣａＣｌ_２ 水溶液６８重量部を徐々に添加し、Ｃａ_３ （ＰＯ_４ ）_２ を含む水系媒体を得た。
【０１１６】
一方、
スチレン ８０部
ｎ−ブチルアクリレート ２０部
カーボンブラック（平均一次粒径＝４０ｎｍ，比表面積＝５０ｍ^２ ／ｇ １０部
ジ−ｔｅｒｔ−ブチルサリチル酸アルミニウム化合物 １部
アゾ系鉄化合物（１） １部
飽和ポリエステル樹脂（ピーク分子量＝７６００，酸価＝８ｍｇＫＯＨ／ｇ）
５部
エステルワックス（ｍ．ｐ．７５℃） １５部
【０１１７】
上記処方を６０℃に加温し、ＴＫ式ホモミキサー（特殊機化工業製）を用いて、１２０００ｒｐｍにて均一に溶解、分散した。これに、重合開始剤２，２′−アゾビス（２，４−ジメチルバレニトリル）５部を溶解し、重合性単量体組成物を調製した。
【０１１８】
前記水系媒体中に上記重合性単量体組成物を投入し、６０℃，Ｎ_２ 雰囲気下において、ＴＫ式ホモミキサーにて１００００ｒｐｍで１０分間撹拌し、重合性単量体組成物を造粒した。その後、パドル撹拌翼で撹拌しつつ、８０℃に昇温し、１０時間反応させた。重合反応終了後、減圧下で残存モノマーを留去し、冷却後、塩酸を加えリン酸カルシウムを溶解させた後、ろ過、水洗、乾燥をして、重量平均径約７．５μｍのシャープな重合体粒子を得た。得られた粒子の物性を表３及び表４に示す。
【０１１９】
得られた粒子９８．５部に対して、ＢＥＴ法による比表面積が２００ｍ^２ ／ｇである疎水性シリカを１．５部外添し、重合トナーＡを得た。このトナー５部に対し、アクリル樹脂コートされた磁性フェライトキャリア９５部を混合し、二成分系現像剤Ａとした。
【０１２０】
トナー形状係数を測定したところ、ＳＦ−１＝１１１、ＳＦ−２＝１０９であった。
【０１２１】
〔重合トナーの製造例Ｂ〜Ｓ〕
製造例Ａにおいて、アゾ系鉄化合物、及びオキシカルボン酸金属化合物の種類及び添加量を、表１及び表２に示すごとく変更して重合体粒子Ｂ〜Ｓを得た。さらに製造例Ａと同様に疎水性シリカを外添し、重合トナーＢ〜Ｓを得、このトナー５部に対し、アクリルコートされたフェライトキャリア９５部を混合し、現像剤Ｂ〜Ｓとした。得られた重合体粒子の物性を表３及び表４に示す。
【０１２２】
〔重合トナーの製造例Ｔ〕
スチレン ６０部
カーボンブラック １０部
アゾ系鉄化合物（１） １部
【０１２３】
上記材料をアトライター１Ｓ（三井鉱山社製）を用いて３時間撹拌し分散させ、マスターバッチ分散液を作製した。
【０１２４】
次に、
上記マスターバッチ分散液 ７１部
スチレン ２０部
ｎ−ブチルアクリレート ２０部
ジ−ｔｅｒｔ−ブチルサリチル酸アルミニウム化合物 １部
飽和ポリエステル樹脂 ５部
エステルワックス １５部
【０１２５】
上記処方を６０℃に加温し、ＴＫ式ホモミキサー（特殊機化工業製）を用いて、１２０００ｒｐｍにて均一に溶解、分散した。これに、重合開始剤２，２′−アゾビス（２，４−ジメチルバレロニトリル）５部を溶解し、重合性単量体組成物を調製した。
【０１２６】
それ以外は、重合トナーの製造例Ａと同様にして、重合体粒子Ｔを得、更に重合トナーＴ、現像剤Ｔを得た。得られた重合体粒子の物性を表２及び表３に示す。
【０１２７】
実施例１
トナーの製造例１で得られた現像剤Ａを使用して、図３に示す市販のカラー複写機ＣＬＣ−５００（キヤノン製）を改造した画像形成装置を用い、黒色モードに設定して画出しを行い、転写効率、帯電立ち上がり特性、帯電安定性、トナー飛散、カブリ、画像濃度に関して評価を行った。それぞれの測定条件及び評価基準を以下に示す。
【０１２８】
まず図３に示す装置を用いた画像形成方法を説明する。
【０１２９】
装置本体内の画像形成部は一つの潜像担持体（感光ドラム）５０１を持ち、その外周は、露光ランプ９、ドラム帯電器２、図示しない光源装置から発せられた光をスキャンする為のポリゴンミラー１３が設けられている。図示しない光源装置から発せられたレーザー光をポリゴンミラー１３を回転することによって走査し、反射ミラーによって光束を変向した走査光を感光ドラム２の母線上に集光するｆθレンズを介して画像信号に応じた静電潜像を形成する。
【０１３０】
次いで現像器３が、潜像に応じて感光ドラム１上に可視像を形成する。更に、記録材カセット１０中にあった転写材としての記録材６は、転写材担持体８上に静電的に担持され、この転写材担持体８は潜像担持体である感光ドラム１と同期して回転し、現像器で現像された可視像転写部において転写帯電器４によって転写される。この工程を順次複数回行い、レジストレーションを合わせつつ、同一記録材上にトナーは重ね合わせられ、この工程が終了すると分離爪等によって記録材担持体８上から記録材６が分離され、搬送ベルトによって定着器７に送られ、定着ローラー１１及び加圧ローラー１２の間を記録材６が通過することにより、加熱及び加圧されて、ただ一回の定着によって画像が得られる。転写材上に転写されずに感光ドラム１の感光体上に残ったトナー粒子は、クリーニング装置５により感光体上から除去される。
【０１３１】
又評価環境は、常温低湿下（２３℃／５％ＲＨ）、常温常湿下（２３℃／６５％ＲＨ）、高温高湿下（３０℃／８０％ＲＨ）において行い、複写機の現像コントラストは、常温低湿下においては４００Ｖ、常温常湿下では３２０Ｖ、高温高湿下では２５０Ｖに設定して評価を行った。
【０１３２】
▲１▼転写効率の評価は、通常環境下において行った。評価方法は、先ず感光体ドラム上にベタ黒画像を形成し、そのベタ黒画像を透明な粘着テープで採取し、その画像濃度（Ｄ１）をカラー反射濃度計（Ｃｏｌｏｒ ｒｅｆｌｅｃｔｉｏｎ ｄｅｎｓｉｔｏｍｅｔｅｒ Ｘ−ＲＩＴＥ ４０４Ａ ｍａｎｕｆａｃｔｕｒｅｄ ｂｙ Ｘ−Ｒｉｔｅ Ｃｏ．）で測定した。次に再度、ベタ黒画像を感光体ドラム上に形成し、ベタ黒画像を記録材へ転写し、記録材上に転写されたベタ黒画像を透明な粘着テープで採取し、その画像濃度（Ｄ２）を測定した。転写効率は、得られた画像濃度（Ｄ１）及び（Ｄ２）から下式に基づき算出した。
【０１３３】
転写効率（％）＝（Ｄ２／Ｄ１）×１００
【０１３４】
▲２▼帯電の立ち上がり特性は、常温低湿下で１０００枚の複写テストを行い、初期からの現像剤の帯電量変化から帯電の立ち上がり特性を評価した。評価は、空回転を３分間行った後、画出しを開始し、その時の帯電量と１０００枚時の帯電量の変化幅を％で表し、以下の基準で行った。
【０１３５】
Ａ：帯電量の変化幅が０〜１０％
Ｂ：帯電量の変化幅が１１〜２０％
Ｃ：帯電量の変化幅が２１〜３０％
Ｄ：帯電量の変化幅が３１〜４０％
Ｅ：帯電量の変化幅が４１〜５０％
Ｆ：帯電量の変化幅が５１％以上
【０１３６】
▲３▼帯電安定性は、高温高湿下で５００００枚の複写テストを行い、現像剤の帯電量変化から帯電安定性を評価した。評価は、１０００枚複写時の帯電量と終了時の帯電量の変化幅を％で表し、以下の基準で行った。
【０１３７】
Ａ：帯電量の変化幅が０〜１０％
Ｂ：帯電量の変化幅が１１〜２０％
Ｃ：帯電量の変化幅が２１〜３０％
Ｄ：帯電量の変化幅が３１〜４０％
Ｅ：帯電量の変化幅が４１〜５０％
Ｆ：帯電量の変化幅が５１％以上
【０１３８】
▲４▼トナー飛散は、高温高湿下において５万枚耐画出し後の現像器を取り出し、空回転器にセットする。現像器のスリーブの真下を中心にＡ４の紙を置き、１０分間の空回転を行い、紙上に落ちたトナーの重量を測定し、以下の基準により評価した。
【０１３９】
Ａ：３ｍｇ以下
Ｂ：４〜６ｍｇ
Ｃ：７〜９ｍｇ
Ｄ：１０〜１２ｍｇ
Ｅ：１３〜１５ｍｇ
Ｆ：１６ｍｇ以上
【０１４０】
▲５▼カブリに関しては、高温高湿下（３０℃／８０％ＲＨ）で、反射濃度計（ｄｅｎｓｉｔｏｍｅｔｅｒ ＴＣ６ＭＣ：（有）東京電色技術センター）を用いて、白紙の反射濃度、及び複写機の紙の非画像部の反射濃度を測定し、両者の反射濃度の差を、白紙の反射濃度を基準として評価した。
【０１４１】
Ａ：０．５％以下
Ｂ：０．６〜１．０％
Ｃ：１．１〜１．５％
Ｄ：１．６〜２．０％
Ｅ：２．１〜４．０％
Ｆ：４．１％以上
【０１４２】
▲６▼画像濃度は、高温高湿下において、初期及び３００００枚の複写終了後にベタ黒画像を複写し、その濃度をマクベス濃度計にて測定した。
【０１４３】
評価結果を表５に示す。
【０１４４】
〔実施例２〜１７及び比較例１〜３〕
用いる現像剤を現像剤Ｂ〜Ｔに代える以外は実施例１と同様にして画出しを行い評価した。評価結果を表５に示す。
【０１４５】
【表１】

【０１４６】
【表２】

【０１４７】
【表３】

【０１４８】
【表４】

【０１４９】
【表５】

【０１５０】
【発明の効果】
本発明のごとく、特定のアゾ系鉄化合物とオキシカルボン酸金属化合物を適正量併用することにより、転写性に優れ、各環境において帯電性が良好で、長期間高画質を維持できる静電荷像現像用トナーを得ることができる。
【図面の簡単な説明】
【図１】転写効率と形状係数との関係図である。
【図２】形状係数と潤滑性との関係図である。
【図３】本発明のトナーを好適に使用し得る画像形成装置の一例を示す概略的説明図である。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an electrostatic image developing toner used in electrophotography.
[0002]
[Prior art]
Conventionally, a number of methods are known as electrophotography. In general, a photoconductive substance is used to form an electric latent image on an image carrier (photoreceptor) by various means. The latent image is developed with a toner to form a visible image, and if necessary, the toner image is transferred to a transfer material such as paper, and then the toner image is fixed on the transfer material by heat, pressure, etc. to obtain a copy. Things.
[0003]
As printer devices, LED and LBP printers have become the mainstream in the recent market, and the direction of technology has been increased to higher resolution, that is, from 240,300 dpi to 400,600,800 dpi. Accordingly, the development method is also required to have higher definition. In addition, the functions of the copiers have also been enhanced, and therefore the digital copier is moving toward digitalization. In this direction, a method of forming an electrostatic charge image with a laser is mainly used, so that the direction is also moving toward a higher resolution, and a high-resolution and high-definition developing method is required similarly to a printer. . For this reason, the particle size of the toner has been reduced, and JP-A-1-112253, JP-A-1-191156, JP-A-2-214156, JP-A-2-284158, and JP-A-3-181952. And Japanese Patent Application Laid-Open No. 4-162048 propose a toner having a specific particle size distribution and a small particle size.
[0004]
The toner image formed on the photoconductor in the development process is transferred to a transfer material in the transfer process. However, the transfer residual toner remaining on the photoconductor is cleaned in a cleaning process, and the toner is stored in a waste toner container. For this cleaning step, conventionally, blade cleaning, fur brush cleaning, roller cleaning, and the like have been used. From the viewpoint of the apparatus, the provision of such a cleaning apparatus inevitably increases the size of the apparatus, which has been a bottleneck when aiming for a more compact apparatus. Furthermore, from the viewpoint of ecology, a system with a small amount of waste toner is desired in terms of effective use of the toner, and a toner having good transfer efficiency has been demanded.
[0005]
For this reason, various attempts have been made to improve the transferability of the toner, one of which is to reduce the frictional force between the photoconductor and the cleaner member by making the toner shape spherical and smoothing the surface, thereby increasing the height of the photoconductor. Attempts have been made to improve the transfer efficiency by obtaining a longer life, reducing the contact area with the photosensitive drum, and reducing the adhesive force.
[0006]
As described above, as a method of producing a spherical toner having a smooth surface, there is a method of producing a toner by a polymerization method. Conventionally, in the production of a toner by a pulverization method, which is generally performed, a step of heating and cooling a melt-kneaded toner composition and then pulverizing the toner composition is performed. Was not smooth. On the other hand, in the production of a toner using the polymerization method proposed in Japanese Patent Publication No. 36-10231, the toner is directly obtained by suspension polymerization of the toner particles. can do.
[0007]
However, as described above, the toner having a spherical and smooth surface has a problem that the contact point with the charging member is small, the charging property is reduced, and the charging property is significantly reduced under high humidity. Has occurred. In order to solve this problem, it is necessary to further improve the chargeability of the conventional toner.
[0008]
Conventionally, in order to retain electric charge in the toner, it is possible to use the frictional charging property of the resin which is a component of the toner, but in this method, since the charging property of the toner is small, an image obtained by development is easily fogged, It tends to be blurred. Therefore, in order to impart a desired triboelectric charging property to the toner, a dye or pigment for imparting charging property, and further, a charge control agent are added.
[0009]
Since the toner containing the charge control agent easily contaminates the toner carrier such as the developing sleeve, the amount of triboelectric charge decreases as the number of copies increases, and the image density tends to decrease. In addition, certain charge control agents have insufficient triboelectric charge and are easily affected by temperature and humidity, and thus tend to cause fluctuations in image density due to environmental fluctuations. Further, since a certain type of charge control agent has poor dispersibility in a resin, a toner using the same tends to have a non-uniform triboelectric charge amount between toner particles and is liable to generate fog. In addition, certain charge control agents have poor storage stability, and the triboelectric charge tends to decrease during long-term storage.
[0010]
Today, as charge control agents known in the art, as negative triboelectrification, metal complex salts of monoazo dyes, salicylic acid, naphthoic acid, metal complex salts of dicarboxylic acids, copper phthalocyanine pigments, resins containing acid components, etc. It has been known. Further, as the positive triboelectric charging property, a nigrosine dye, an azine dye, a triphenylmethane dye, a quaternary ammonium salt, or a resin having a quaternary ammonium salt in a side chain is known.
[0011]
Among these, various metal complexes are disclosed in JP-B-43-17955, JP-B-55-42752, JP-A-61-155664, JP-B-63-1994, and JP-A-8-272146. Have been proposed as negative charge control agents. Although these do show good chargeability, they have not been sufficient for the above-mentioned spherical toner having a smooth surface, and improvements have been desired.
[0012]
In addition, poor dispersibility of carbon black has been a problem for some time, but it is a serious problem particularly in the production of toner by a polymerization method, and improvement has been desired.
[0013]
[Problems to be solved by the invention]
SUMMARY OF THE INVENTION An object of the present invention is to provide a toner for developing an electrostatic image, which solves the above problems.
[0014]
An object of the present invention is to provide a toner for developing an electrostatic charge image having excellent transferability.
[0015]
SUMMARY OF THE INVENTION An object of the present invention is to provide a toner for developing an electrostatic charge image which exhibits good chargeability under various environments such as high temperature and high humidity and low temperature and low humidity.
[0016]
An object of the present invention is to provide a toner for developing an electrostatic image capable of obtaining a high-quality image for a long period of time.
[0017]
An object of the present invention is to provide a production method capable of suitably producing the above toner.
[0018]
[Means for Solving the Problems]
The present invention provides at least a binder resin, carbon black, a compound represented by the formula (2In the toner for developing an electrostatic image having toner particles containing an azo-based iron compound and a metal oxycarboxylate represented by the formula (1), the toner particles are a polymerizable monomer, carbon black, and a compound represented by the formula (2A) preparing a polymerizable monomer composition containing an azo iron compound and a metal oxycarboxylate represented by the formula (I), dispersing the polymerizable monomer composition in an aqueous medium to form a polymerizable monomer; A toner for developing an electrostatic image, comprising toner particles produced through a step of forming particles of the composition and a step of polymerizing a polymerizable monomer in the particles to form a binder resin. .
[0019]
[Outside 5]

[Wherein, R ₁ And R ₃ Is a hydrogen atom, C ₁ ~ ₁₈ An alkyl group of C ₂ ~ ₁₈ Alkenyl group, sulfonamide group, mesyl group, sulfonic acid group, hydroxy group, C ₁ ~ ₁₈ An alkoxy group, an acetylamino group, a benzoylamino group, a halogen atom and
[0020]
[Outside 6]

An atom or a functional group selected from the group consisting of functional groups represented by ₁ And R ₃ May be the same or different, and n and n 'each represent an integer of 1 to 3; ₅ Is C ₁ ~ ₁₈ An alkyl group or C ₆ ~ ₁₈ Represents an aryl group of
R ₂ And R ₄ Represents a hydrogen atom or a nitro group; ₂ And R ₄ May be the same or different,
X ₁ And X ₂ Is a hydrogen atom, C ₁ ~ ₅ An alkyl group of C ₁ ~ ₅ X represents an atom or a functional group selected from the group consisting of an alkoxy group, a nitro group and a halogen atom; ₁ And X ₂ May be the same or different, m and m 'represent an integer of 1 to 3,
A ⁺ Represents an ion selected from the group consisting of a hydrogen ion, a sodium ion, a potassium ion, and an ammonium ion, or a mixture thereof. ]
[0022]
The present invention comprises at least the following steps,
i) polymerizable monomer, carbon black, formula (2A) a step of preparing a polymerizable monomer composition containing an azo-based iron compound and a metal oxycarboxylate represented by
ii) a step of dispersing the polymerizable monomer composition in an aqueous medium to produce particles of the polymerizable monomer composition;
iii) producing toner particles by polymerizing the polymerizable monomer in the particles,
The present invention relates to a method for producing a toner for developing electrostatic images having toner particles, characterized by having:
[0023]
[Outside 7]

[Wherein, R ₁ And R ₃ Is a hydrogen atom, C ₁ ~ ₁₈ An alkyl group of C ₂ ~ ₁₈ Alkenyl group, sulfonamide group, mesyl group, sulfonic acid group, hydroxy group, C ₁ ~ ₁₈ An alkoxy group, an acetylamino group, a benzoylamino group, a halogen atom and
[0024]
[Outside 8]

An atom or a functional group selected from the group consisting of functional groups represented by ₁ And R ₃ May be the same or different, and n and n 'each represent an integer of 1 to 3; ₅ Is C ₁ ~ ₁₈ An alkyl group or C ₆ ~ ₁₈ Represents an aryl group of
R ₂ And R ₄ Represents a hydrogen atom or a nitro group; ₂ And R ₄ May be the same or different,
X ₁ And X ₂ Is a hydrogen atom, C ₁ ~ ₅ An alkyl group of C ₁ ~ ₅ X represents an atom or a functional group selected from the group consisting of an alkoxy group, a nitro group and a halogen atom; ₁ And X ₂ May be the same or different, m and m 'represent an integer of 1 to 3,
A ⁺ Represents an ion selected from the group consisting of a hydrogen ion, a sodium ion, a potassium ion, and an ammonium ion, or a mixture thereof. ]
[0026]
BEST MODE FOR CARRYING OUT THE INVENTION
As described above, since the toner having a spherical shape and a smooth surface has a small contact point with the charging member, the charging property is lowered under high humidity, and the toner is easily scattered or fogged. In order to solve this problem, if the charge amount is increased, the charge amount becomes excessively large under low humidity, which causes a decrease in the density of the obtained image and a deterioration in transfer efficiency.
[0027]
The present inventors have solved this problem by using a specific azo-based iron compound and a metal oxycarboxylate compound in combination.
[0028]
A developer using a metal compound of an organic acid generally used as a charge control agent may exhibit relatively high chargeability, but the charge amount is reduced under high humidity, and the charge speed is reduced under low humidity. There is a decrease.
[0029]
The reason for this is considered to be the adsorption and desorption of moisture near the metal. Under high humidity, the amount of water adsorbed on the metal compound increases, so that the charge amount decreases. It is considered that the charging rate increases and the charging speed decreases.
[0030]
On the other hand, when an organic acid having a low negative charge density on carboxyl group oxygen, such as oxycarboxylic acid, is used, a high charge amount can be obtained even under high humidity. In this regard, when the negative charge density on the carboxyl group oxygen is small, the electron density on the metal atom does not increase so much even when bonded to the metal, and it is considered that the negative charge ability of the metal compound is high.
[0031]
In particular, high effects were found for aromatic oxycarboxylic acids. Although the reason for this is not clear, the aromatic oxycarboxylic acid has a smaller negative charge density on the carboxyl oxygen due to its resonance structure, and has a sterically large structure, so that the water molecule is bound to the bound metal molecule. Can be easily blocked.
[0032]
Some developers containing a metal oxycarboxylate compound have been disclosed. For example, a chromium salicylate compound is disclosed in JP-B-55-42752, a zinc salicylate compound is disclosed in JP-A-63-2074 and JP-A-63-33755, and JP-A-63-208865 is disclosed. JP-A-63-237065 and JP-A-64-10261 disclose aluminum compounds of salicylic acid.
[0033]
However, the present inventors have studied that the toner having a spherical and smooth surface as in the present invention has a low charging rate under low humidity, and a difference in the charging characteristics between the initial stage and the endurance period, when only the metal oxycarboxylate compound is used. And the image density was lowered.
[0034]
Thus, the present inventors have found that when the azo-based iron compound represented by the general formula (1) is used in combination, it is possible to prevent a decrease in the charging speed under low humidity and to further improve the charging under high humidity. It was.
[0035]
When this azo-based iron compound is used alone as a charge control agent, the charge speed is good and the rise of the charge amount can be solved, but the absolute value of the charge amount is low, and scattering and fogging under high humidity are problematic. there were.
[0036]
However, according to the study of the present inventors, when a specific azo-based iron compound and a metal oxycarboxylate compound are used in combination, a greater effect is obtained than when the performance of each compound is added, and the chargeability under each environment is improved. They have found a significant improvement.
[0037]
Although the reason is not clear, it is considered that the combined use improves the dispersibility of each other in the toner and provides more effective performance, thereby improving the environmental characteristics.
[0038]
The constitution of the present invention has a great effect on the toner formed by the polymerization method, and in particular, it has become possible to greatly improve the charging characteristics under high humidity.
[0039]
Although the reason is not clear, the dispersibility of carbon black, which is a commonly used pigment, is significantly improved by the azo-based iron compound of the present invention. Therefore, the formation of the conductive path by the conductive carbon black is small, and the carbon black existing on the toner surface is also small, so that the leakage of the negative charge is suppressed and the charge amount is increased.
[0040]
Further, in the study of the present inventors, the addition amount of the azo-based iron compound and the metal oxycarboxylate is such that the addition amount of the azo-based iron compound is A parts by weight, and the addition amount of the metal oxycarboxylate is B parts by weight. Department
0.1 ≦ A / B ≦ 20
It is preferable that Although the reason is not clear, it is considered that the dispersion state of each compound in the toner changes, and the synergistic effect as described above cannot be obtained. If it is less than 0.1 or exceeds 20, the rising of charging under low humidity is deteriorated and the charge amount under high humidity is reduced.
[0041]
The azo-based iron compound used in the present invention has the following formula (2).
[0046]
[Outside 20]

[Wherein, R₁  And R₃  Is a hydrogen atom, C₁  ~₁₈An alkyl group of C₂  ~₁₈Alkenyl group, sulfonamide group, mesyl group, sulfonic acid group, hydroxy group, C₁  ~₁₈An alkoxy group, an acetylamino group, a benzoylamino group, a halogen atom and
[0047]
[Outside 21]

An atom or a functional group selected from the group consisting of functional groups represented by₁  And R₃  May be the same or different, and n and n 'each represent an integer of 1 to 3;₅  Is C₁  ~₁₈An alkyl group or C₆  ~₁₈R represents an aryl group of₂  And R₄  Represents a hydrogen atom or a nitro group;₂  And R₄  May be the same or different, and X₁  And X₂  Is a hydrogen atom, C₁  ~₅  An alkyl group of C₁  ~₅  X represents an atom or a functional group selected from the group consisting of an alkoxy group, a nitro group and a halogen atom;₁  And X₂  And m and m 'each represent an integer of 1 to 3,⁺  Represents an ion selected from the group consisting of a hydrogen ion, a sodium ion, a potassium ion, and an ammonium ion, or a mixture thereof. ]
[0048]
Representative specific examples of the azo-based iron compound of the general formula include the following compounds.
[0049]
[Outside 22]

[0050]
[Outside 9]

[0051]
The azo-based iron compound that can be used in the present invention is generally prepared by a coupling reaction between a diazotized substituted aminophenol and a substituted naphthol, and then binding the resulting product to an iron salt such as iron sulfide. it can.
[0052]
The azo iron compound is used in an amount of 0.1 to 8 parts by weight, preferably 0.1 to 6 parts by weight, based on 100 parts by weight of the binder resin. If the amount is less than 0.1 part by weight, the above-mentioned effect is small. If the amount exceeds 8 parts by weight, contamination of the charging member or the like occurs.
[0053]
Next, in the oxycarboxylic acid metal compound used in the present invention, examples of the oxycarboxylic acid used include malic acid, dimethylolbutanoic acid, tartaric acid, citric acid, salicylic acid, and hydroxynaphthoic acid. Among them, alkyl salicylic acid and dialkyl salicylic acid having an alkyl group having 5 or less carbon atoms are preferable, and 3,5-dialkyl salicylic acid is particularly preferable. As the alkyl group, a t-butyl group is most preferably used.
[0054]
Other compounds include 2-hydroxy-3-naphthoic acid, alkyl-2-hydroxy-3-naphthoic acid having 5 or less carbon atoms, and 5,6,7,8-tetrahalogen-2-hydroxy-3-acid. Naphthoic acid and the like are used.
[0055]
On the other hand, examples of the metal atom used include aluminum, zinc, chromium, cobalt, nickel, copper, iron, and zirconia.In the study of the present inventors, the compound of aluminum and zinc is the azo-based iron. The effect is great when used in combination with a compound, which is particularly preferred.
[0056]
As preferred oxycarboxylic acid metal compounds, the following compounds are exemplified.
[0057]
[Outside 24]

[In the formula, A represents hydrogen, an alkali metal or an alkaline earth metal. ]
[0058]
[Outside 25]

[0059]
[Outside 26]

[0060]
[Outside 27]

[0061]
The addition amount of the metal oxycarboxylate according to the present invention is 0.1 to 10 parts by weight, preferably 1 to 6 parts by weight, based on 100 parts by weight of the binder resin. When the amount is less than 0.1 part by weight, the above-mentioned effect is small, and when the amount exceeds 10 parts by weight, contamination of a charging member or the like occurs as in the case of the azo-based iron compound.
[0062]
In the toner of the present invention, it is preferable that SF-1 indicating the shape factor of the toner is 100 to 140, and SF-2 is 100 to 120. SF-1 and SF-2 indicating the shape factor used in the present invention are obtained by randomly sampling 100 toner images using FE-SEM (S-800) manufactured by Hitachi, Ltd., and the image information is transmitted via an interface. In the present invention, the values were calculated by the following equation after being introduced into an image analyzer (Luzex3) manufactured by Nicolet and analyzed, and defined in the present invention as shape factors SF-1 and SF-2.
[0063]
SF-1 = ｛(MXLNG)²  / AREA ×× (π / 4) × 100
SF-2 = ｛(PERI)²  / AREA｝ × (1 / 4π) × 100
(Where AREA = toner projected area, MXLNG = absolute maximum length, PERI = perimeter of toner image)
[0064]
That is, the shape factor SF-1 of the toner indicates a spherical degree, and if it is larger than 140, it deviates from a spherical shape and approaches an irregular shape. SF-2 indicates the degree of unevenness, and if it is larger than 120, the unevenness on the toner surface becomes remarkable.
[0065]
The advantages of controlling the shape factor of the toner to be small as described above will be described below. First, since the contact area with the photosensitive drum is reduced, the adhesive force is reduced, and the transfer can be performed with high efficiency.
[0066]
Figure1Fig. 3 shows the correlation between the transfer efficiency and the shape factor. From this figure, it can be seen that the smaller the shape factor, the higher the transfer efficiency. As a result, the amount of transfer residual toner collected in the cleaning machine becomes extremely small, and the size of the cleaning device can be reduced.
[0067]
As a second effect, by using a toner having a spherical, smooth, and uniform surface, the charge of the toner after being transferred to the transfer material is constant. The re-transfer phenomenon that the removed toner is electrostatically peeled off on the photosensitive drum in the current image forming section can be prevented. As a result, a high quality image can be obtained without disturbing the toner on the transfer material.
[0068]
Third, a small-diameter photosensitive drum can be used. That is, by making the shape factor spherical and smoothing the surface, the frictional force between the photosensitive drum and the cleaner member can be reduced, and wear of the photosensitive drum can be prevented.
[0069]
Figure2Fig. 6 shows the correlation between the shape factor and lubricity. The measurement was carried out by applying a toner onto glass, placing a urethane rubber on which a 300 g weight was placed, and measuring the load that began to move when pulled from the lateral direction. From this figure, it is clear that the smaller the shape factor, the higher the lubricity. Even when a test was actually performed on the apparatus, the wear of the photosensitive drum was extremely small, and a long life was achieved.
[0070]
However, if the shape factor is spherical and the surface is smoothed to obtain the above effect, the contact point between the toner surface and the charging member is smaller than that of the amorphous toner as described above, For example, toner scattering and fogging under high humidity became a problem.
[0071]
However, by employing the toner having the configuration of the present invention, it was possible to achieve high transfer efficiency, prevent retransfer, and employ a small-diameter drum while ensuring good chargeability.
[0072]
The following method can be used to make the shape of the toner of the present invention within the above range.
[0073]
JP-B-36-10231, JP-A-59-53856, and JP-A-59-61842 disclose a method of directly producing a toner using a suspension polymerization method, and a method for producing a monomer. Emulsion polymerization typified by a dispersion polymerization method in which a soluble polymer is directly formed into a toner using an insoluble aqueous organic solvent or a soap-free polymerization method in which a toner is formed by direct polymerization in the presence of a water-soluble polar polymerization initiator The toner can be manufactured using a method or the like.
[0074]
In the present invention, the shape factor SF-1 of the toner can be easily controlled to 100 to 140 and SF-2 to 100 to 120, and a fine particle toner having a sharp particle size distribution and a particle size of 3 to 10 μm can be obtained relatively easily. The suspension polymerization method under normal pressure or under pressure is particularly preferred. To control the particle size distribution and the particle size of the toner, the method of changing the type and amount of the hardly water-soluble inorganic salt and the dispersant that acts as a protective colloid, and the mechanical device conditions such as the peripheral speed of the rotor, the number of baths, and the stirring blade The predetermined toner of the present invention can be obtained by controlling the stirring conditions such as the shape, the shape of the container, and the solid content concentration in the aqueous solution.
[0075]
As the resin used for the toner of the present invention, generally used styrene polymers such as styrene-acryl copolymers and styrene-methacryl copolymers can be used.
[0076]
In a method of directly obtaining a toner by a polymerization method, those monomers are preferably used. Specifically, styrene-based monomers such as styrene, o (m-, p-)-methylstyrene, m (p-)-ethylstyrene; methyl (meth) acrylate, ethyl (meth) acrylate, ( Propyl (meth) acrylate, butyl (meth) acrylate, octyl (meth) acrylate, dodecyl (meth) acrylate, stearyl (meth) acrylate, behenyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, (Meth) acrylate monomers such as dimethylaminoethyl (meth) acrylate and diethylaminoethyl (meth) acrylate; preferably monomers such as butadiene, isoprene, cyclohexene, (meth) acrylonitrile, and acrylamide Used. These can be used alone or in general so that the theoretical glass temperature (Tg) described in the published Polymer Handbook, 2nd edition III-P139-192 (manufactured by John Wiley & Sons) is 40 to 75 ° C. It is used after being appropriately mixed. If the theoretical glass transition temperature is lower than 40 ° C., problems arise in terms of the storage stability of the toner and the durability stability of the developer. On the other hand, if the theoretical glass transition temperature exceeds 75 ° C., the fixing point rises. In such a case, the color mixture of the toners of each color is insufficient, resulting in poor color reproducibility, and furthermore, the transparency of the OHP image is significantly reduced, which is not preferable in terms of high image quality.
[0077]
The molecular weight of the binder resin is measured by GPC (gel permeation chromatography). As a specific GPC measurement method, after extracting the toner in advance with a toluene solvent using a Soxhlet extractor for 20 hours, the toluene is distilled off with a rotary evaporator, and the ester wax is dissolved, but the binder resin is dissolved. After adding an organic solvent that cannot be dissolved, such as chloroform, and washing well, the solution dissolved in THF (tetrahydrofuran) was filtered through a solvent-resistant membrane filter having a pore diameter of 0.3 μm. The column structure used is A-801, 802, 803, 804, 805, 806, 807 manufactured by Showa Denko, and the molecular weight distribution can be measured using a calibration curve of a standard polystyrene resin. The number average molecular weight (Mn) of the obtained resin component is 5,000 to 1,000,000, and the ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is 2 to 100. The binder resins shown are preferred for the present invention.
[0078]
Further, a polymer or copolymer having a polar group may be added to the monomer system of the polymerization method toner in the present invention.
[0079]
The polar polymer and polar copolymer that can be used in the present invention are exemplified below.
[0080]
Polymers of nitrogen-containing monomers such as dimethylaminoethyl methacrylate and diethylaminoethyl methacrylate, copolymers such as styrene-unsaturated carboxylic esters, nitrile monomers such as acrylonitrile, and halogen-containing monomers such as vinyl chloride Polymers, such as unsaturated carboxylic acids of acrylic acid and methacrylic acid, other unsaturated dibasic acids, unsaturated dibasic acid anhydrides, polymers such as nitro monomers or copolymers with styrene monomers , Polyester, polycarbonate, epoxy resin and the like.
[0081]
In the present invention, carbon black is used as a coloring agent. Among them, the average primary particle size is 10 to 70 nm, and the specific surface area by nitrogen adsorption is 100 m.²  / G, a volatile content of 2% or less, a pH of 2 or less, and a DBP oil absorption of 50 to 200 ml / 100 g are preferably used. The amount of carbon black is 1 to 20 parts by weight based on 100 parts by weight of the binder resin.
[0082]
The average primary particle size of the carbon black is preferably from 10 to 70 nm, more preferably from 20 to 60 nm, and still more preferably from 25 to 45 nm. When the primary particle size of carbon black is less than 10 nm, when used in combination with the specific azo-based iron compound used in the present invention, the viscosity becomes too large, it is difficult to master, and further, the average primary particle size is very small. Due to the fineness, it is difficult to obtain sufficient dispersibility. Further, when the average primary particle size of the carbon black is larger than 70 nm, the coloring power of the toner becomes too low even if dispersed well, and if used in large amounts to increase the coloring power, the charge of the toner is reduced. It is not suitable for use.
[0083]
The pH of the carbon black is preferably 2 or more, more preferably 4 or more. When the pH is lower than 2, many functional groups are present on the surface of the carbon black, and it is easy to cause polymerization inhibition.
[0084]
The specific surface area of carbon black due to nitrogen adsorption is 100 m²  / G or less, more preferably 30 to 90 m²  / G, more preferably 40 to 90 m²  / G. The volatile matter of the carbon black is preferably 2% or less, more preferably 0.1 to 1.8%, and still more preferably 0.1 to 1.7%. Specific surface area is 100m²  If it exceeds / g, polymerization inhibition is likely to occur, and if the volatile content exceeds 2%, it is not suitable for use because a large number of polymerization inhibiting groups are present on the surface of carbon black.
[0085]
The DBP oil absorption of carbon black is preferably 50 to 200 ml / 100 g, more preferably 110 to 200 ml / 100 g, and even more preferably 120 to 160 ml / 100 g. If the DBP oil absorption is less than 50 ml / 100 g, the dispersibility of the carbon black in the toner particles is not sufficient, and the colorability tends to decrease. On the other hand, if it exceeds 200 ml / 100 g, the conductivity of the toner surface becomes too high, and in particular, the electrification under high humidification decreases, which is not preferable.
[0086]
The addition amount of carbon black is 1 to 20 parts by weight based on 100 parts by weight of the binder resin, but it is preferable that the following relationship be satisfied between the addition amount of the azo-based iron compound and the dispersibility. . When the addition amount of the azo-based iron compound is A parts by weight and the addition amount of carbon black is C parts by weight,
3 ≦ C / A ≦ 50
Preferably, and more preferably
3 ≦ C / A ≦ 38
Meet.
[0087]
If the amount of the azo-based iron compound is too small relative to the carbon black, the viscosity does not increase, and the carbon black is difficult to be stably dispersed. In this case, carbon black precipitates with the lapse of time, and it is difficult to obtain sufficient coloring power when a toner is produced using this dispersion.
[0088]
If the amount of the azo-based iron compound is too large relative to the carbon black, the azo-based iron compound is liable to cause secondary agglomeration and dispersibility is reduced, and the secondary agglomerate is liable to cause polymerization inhibition and is taken out as toner particles. Becomes difficult.
[0089]
Next, methods for measuring various physical properties of carbon black will be described.
[0090]
(1) DBP oil absorption of carbon black
According to Method A described in JIS K 6221, DBP oil absorption is determined by dropping DBP onto a dry sample (carbon black).
[0091]
(2) Measurement of specific surface area by nitrogen adsorption of carbon black
The measurement is performed according to ASTM D3037.
[0092]
(3) Measurement of volatile matter of carbon black
The volatile matter is determined by measuring the mass of the dried sample before and after heating according to JIS K6221.
[0093]
(4) Measurement of average primary particle size of carbon black
It measures according to ASTM D3849-89 using a transmission electron microscope.
[0094]
(5) Measurement of pH of carbon black
According to JIS K 6221, water is added to the sample, and after boiling, the supernatant is removed and the pH of the sample is measured.
[0095]
Although the toner of the present invention is a black toner containing carbon black, it can be used in combination with a yellow toner, a magenta toner, and a cyan toner to form a full-color image.
[0096]
Also, the toner of the present invention, MagneticIt can also be used as a magnetic toner containing an isotropic substance. When a magnetic toner is used, it is added in an amount of 40 to 150 parts by weight based on 100 parts by weight of the binder resin.
[0097]
When producing toner particles by a direct polymerization method, for example, 2,2'-azobis- (2,4-dimethylvaleronitrile), 2,2'-azobisisobutyronitrile, Azo or diazo polymerization initiators such as 1,1'-azobis (cyclohexane-1-carbonitrile), 2,2'-azobis-4-methoxy-2,4-dimethylvaleronitrile and azobisisobutyronitrile; Peroxide polymerization initiators such as benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, cumene hydroperoxide, 2,4-dichlorobenzoyl peroxide, and lauroyl peroxide are used.
[0098]
The amount of the polymerization initiator varies depending on the desired degree of polymerization, but is generally used in an amount of 0.5 to 20% by weight based on the monomer. The type of the polymerization initiator varies slightly depending on the polymerization method, but may be used alone or in combination with reference to the 10-hour half-life temperature.
[0099]
In order to control the degree of polymerization, a known crosslinking agent, chain transfer agent, polymerization inhibitor or the like may be further added and used.
[0100]
When the suspension polymerization is used as the toner production method of the present invention, for example, tricalcium phosphate, magnesium phosphate, aluminum phosphate, zinc phosphate, calcium carbonate, magnesium carbonate as an inorganic oxide as a dispersant to be used. , Calcium hydroxide, magnesium hydroxide, aluminum hydroxide, calcium metasilicate, calcium sulfate, barium sulfate, bentonite, silica, alumina, magnetic material, ferrite and the like. As the organic compound, for example, polyvinyl alcohol, gelatin, methylcellulose, methylhydroxypropylcellulose, ethylcellulose, sodium salt of carboxymethylcellulose, starch and the like are used by being dispersed in an aqueous phase. It is preferable to use 0.2 to 10 parts by weight of these dispersants based on 100 parts by weight of the polymerizable monomer.
[0101]
As these dispersants, commercially available ones may be used as they are, but the inorganic compound can also be formed in a dispersion medium under high-speed stirring in order to obtain fine and uniform dispersed particles. For example, in the case of tricalcium phosphate, a dispersant suitable for a suspension polymerization method can be obtained by mixing an aqueous solution of sodium phosphate and an aqueous solution of calcium chloride under high-speed stirring. Further, 0.001 to 0.1 parts by weight of a surfactant may be used in combination for making these dispersants finer. Specifically, commercially available nonionic, anionic, and cationic surfactants can be used, for example, sodium dodecyl sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, sodium oleate, sodium laurate, potassium stearate, and olein. Calcium acid and the like are preferably used.
[0102]
According to the present invention, when a direct polymerization method is used, a toner can be specifically manufactured by the following manufacturing method. A monomer composition obtained by adding carbon black, a charge control agent, a polymerization initiator, and other additives to a monomer and uniformly dissolving or dispersing the mixture using a homogenizer, an ultrasonic disperser, etc., and containing a dispersion stabilizer. In an aqueous phase to be dispersed using a conventional stirrer, homomixer, homogenizer or the like. Preferably, the stirring speed and time are adjusted so that the droplets of the monomer composition have the desired size of the toner particles, and the granulation is performed. After that, by the action of the dispersion stabilizer, the stirring may be performed to such an extent that the particle state is maintained and the sedimentation of the particles is prevented. The polymerization is carried out at a polymerization temperature of 40 ° C. or higher, generally 50 to 90 ° C. In addition, the temperature may be raised in the latter half of the polymerization reaction. Further, in order to improve the durability in the image forming method using the toner of the present invention, the temperature of the toner may be reduced by removing unreacted polymerizable monomers and by-products. In the latter half of the reaction, or after the completion of the reaction, a part of the aqueous medium may be distilled off. After completion of the reaction, the generated toner particles are collected by washing and filtration, and dried. In the suspension polymerization method, it is generally preferable to use 300 to 3000 parts by weight of water as a dispersion medium with respect to 100 parts by weight of the monomer system.
[0103]
In the present invention, in order to disperse carbon black more uniformly, it is a preferable method by using the following master batch process.
[0104]
Before dissolving and dispersing by adding carbon black, a charge control agent, a polymerization initiator, and other additives to the polymerizable monomer, carbon black and azo-based iron are partially added to the polymerizable monomer. Mix only the compounds. By doing so, the carbon black can be mixed at a very high concentration with respect to the polymerizable monomer, so that the concentration of the dispersion is increased and a sufficient share at the time of mixing is required. In combination with the effect, the dispersibility of carbon black can be dramatically improved.
[0105]
In the present invention, the toner preferably has a weight average particle diameter (D4) of 3.0 to 10.0 μm, preferably 3.0 to 8.0 μm.
[0106]
When the volume average particle diameter of the toner is 10.0 μm or less, the highlight reproducibility becomes better. When the toner is 3.0 μm or more, charge-up is difficult particularly in a low humidity environment, and the image density decreases. It becomes difficult.
[0107]
For the measurement of the particle size distribution of the toner of the present invention, a Coulter Counter TA-II or Coulter Multisizer (manufactured by Coulter Inc.) is used. As the electrolyte, 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 measurement method, 0.1 to 5 ml of a surfactant, preferably an alkylbenzene sulfonate, is added as a dispersant to 100 to 150 ml of the electric field 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 dispersion treatment for about 1 to 3 minutes using an ultrasonic disperser, and the volume and number of toner particles having a size of 2 μm or more are measured using the above-mentioned measuring device with an aperture of 100 μm. Distribution was calculated.
[0108]
Then, a weight-average particle diameter (D4) and a volume-average particle diameter (Dv) on a weight basis determined from the volume distribution according to the present invention (each median value of each channel is a representative value for each channel) were determined.
[0109]
The developing method used in the present invention can support both one-component development and two-component development. When the two-component magnetic brush developing method is used, ferrite, magnetite, iron powder, or a carrier coated with an acrylic resin, a silicone resin, a fluororesin, or the like is used as the carrier. Either a magnetic toner or a non-magnetic toner may be used as the one-component developer.
[0110]
【Example】
Hereinafter, the present invention will be described in more detail with reference to Examples, which do not limit the present invention in any way. The parts in the following formulations are parts by weight unless otherwise specified.
[0111]
(Aluminum compound production example 1)
0.2 mol of di-tert-butylsalicylic acid was mixed with 1 l of an aqueous solution of 0.25 mol / l of NaOH and dissolved by heating. This solution is₂  (SO₄  )₃  The solution was added to 1 liter of a 0.05 mol / l aqueous solution, heated and stirred, and then separated by filtration under a condition from neutral to weakly alkaline. The collected white precipitate was washed with water until the washing water became neutral, and then dried to obtain an aluminum di-tert-butylsalicylate compound as a target product.
[0112]
Further, as a result of analyzing the FD mass spectrum of the product, it was confirmed that the main component was a compound in which the composition ratio of oxycarboxylic acid to aluminum was 3: 2.
[0113]
(Aluminum compound production example 2)
An aluminum compound of 2-hydroxynaphthalene-3-carboxylate having almost 100% purity was obtained by a synthesis method similar to that of Production Example 1 of aluminum compound except that 2-hydroxynaphthalene-3-carboxylic acid was used instead of di-tert-butylsalicyl. Got.
[0114]
(Zinc compound production example 1)
Al₂  (SO₄  )₃  Instead of ZnSO₄  A zinc di-tert-butylsalicylate compound was obtained by a synthesis method similar to that of Production Example 1 of an aluminum compound except that an aqueous solution was used.
[0115]
[Production Example A of Polymerized Toner]
0.1M-Na in 710 parts by weight of ion-exchanged water₃  PO₄  After 450 parts by weight of the aqueous solution was charged and heated to 60 ° C., the mixture was stirred at 12000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo). 1.0M-CaCl₂  68 parts by weight of an aqueous solution is gradually added, and Ca₃  (PO₄  )₂  Was obtained.
[0116]
on the other hand,
80 parts of styrene
n-butyl acrylate 20 parts
Carbon black (average primary particle size = 40 nm, specific surface area = 50 m²  / G 10 parts
Aluminum di-tert-butylsalicylate compound 1 part
Azo-based iron compound (1) 1 part
Saturated polyester resin (peak molecular weight = 7600, acid value = 8 mgKOH / g)
5 copies
15 parts of ester wax (mp 75 ° C)
[0117]
The above formulation was heated to 60 ° C., and uniformly dissolved and dispersed at 12000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo). Into this, 5 parts of a polymerization initiator 2,2'-azobis (2,4-dimethylvalenitrile) was dissolved to prepare a polymerizable monomer composition.
[0118]
The polymerizable monomer composition is charged into the aqueous medium,₂  Under an atmosphere, the mixture was stirred with a TK homomixer at 10,000 rpm for 10 minutes to granulate a polymerizable monomer composition. Thereafter, while stirring with a paddle stirring blade, the temperature was raised to 80 ° C., and the reaction was performed for 10 hours. After completion of the polymerization reaction, residual monomers are distilled off under reduced pressure, and after cooling, hydrochloric acid is added to dissolve calcium phosphate, followed by filtration, washing with water, and drying to obtain sharp polymer particles having a weight average diameter of about 7.5 μm. Got. Tables 3 and 4 show the physical properties of the obtained particles.
[0119]
The specific surface area by the BET method was 200 m with respect to 98.5 parts of the obtained particles.²  / G of hydrophobic silica was externally added to obtain Polymerized Toner A. Five parts of the toner was mixed with 95 parts of a magnetic ferrite carrier coated with an acrylic resin to obtain a two-component developer A.
[0120]
When the toner shape factor was measured, SF-1 = 111 and SF-2 = 109.
[0121]
[Production Examples B to S of Polymerized Toner]
In Production Example A, polymer particles B to S were obtained by changing the types and amounts of the azo-based iron compound and the metal oxycarboxylate as shown in Tables 1 and 2. Further, hydrophobic silica was externally added in the same manner as in Production Example A to obtain polymerized toners B to S. Five parts of this toner was mixed with 95 parts of an acryl-coated ferrite carrier to obtain developers B to S. The physical properties of the obtained polymer particles are shown in Tables 3 and 4.
[0122]
[Production Example T of Polymerized Toner]
Styrene 60 parts
10 parts of carbon black
Azo-based iron compound (1) 1 part
[0123]
The above materials were stirred and dispersed for 3 hours using an attritor 1S (manufactured by Mitsui Mining Co., Ltd.) to prepare a master batch dispersion.
[0124]
next,
71 parts of the above master batch dispersion
Styrene 20 parts
n-butyl acrylate 20 parts
Aluminum di-tert-butylsalicylate compound 1 part
5 parts of saturated polyester resin
15 parts of ester wax
[0125]
The above formulation was heated to 60 ° C., and uniformly dissolved and dispersed at 12000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo). Into this, 5 parts of a polymerization initiator 2,2'-azobis (2,4-dimethylvaleronitrile) was dissolved to prepare a polymerizable monomer composition.
[0126]
Otherwise, in the same manner as in Production Example A of the polymerized toner, polymer particles T were obtained, and further, a polymerized toner T and a developer T were obtained. The physical properties of the obtained polymer particles are shown in Tables 2 and 3.
[0127]
Example 1
Using the developer A obtained in Production Example 1 of the toner, an image forming apparatus modified from a commercially available color copying machine CLC-500 (manufactured by Canon) shown in FIG. Then, the transfer efficiency, the charge rising characteristic, the charge stability, the toner scattering, the fog, and the image density were evaluated. The respective measurement conditions and evaluation criteria are shown below.
[0128]
First, an image forming method using the apparatus shown in FIG. 3 will be described.
[0129]
The image forming section in the apparatus main body has one latent image carrier (photosensitive drum) 501, and its outer periphery is a polygon for scanning light emitted from an exposure lamp 9, a drum charger 2, and a light source device (not shown). A mirror 13 is provided. Laser light emitted from a light source device (not shown) is scanned by rotating the polygon mirror 13, and an image signal is transmitted through an fθ lens that condenses the scanning light whose light flux has been redirected by the reflection mirror on the generatrix of the photosensitive drum 2. To form an electrostatic latent image corresponding to.
[0130]
Next, the developing device 3 forms a visible image on the photosensitive drum 1 according to the latent image. Further, the recording material 6 serving as a transfer material in the recording material cassette 10 is electrostatically supported on a transfer material carrier 8, and the transfer material carrier 8 is connected to the photosensitive drum 1 as a latent image carrier. It rotates synchronously and is transferred by the transfer charger 4 in the visible image transfer portion developed by the developing device. This process is sequentially performed a plurality of times, and while the registration is being performed, the toner is superimposed on the same recording material. When this process is completed, the recording material 6 is separated from the recording material carrier 8 by a separation claw or the like, and the conveyance belt Then, the recording material 6 is heated and pressed by passing the recording material 6 between the fixing roller 11 and the pressure roller 12, and an image is obtained by a single fixing. The toner particles remaining on the photosensitive member of the photosensitive drum 1 without being transferred onto the transfer material are removed from the photosensitive member by the cleaning device 5.
[0131]
The evaluation was performed under normal temperature and low humidity (23 ° C / 5% RH), normal temperature and normal humidity (23 ° C / 65% RH), and high temperature and high humidity (30 ° C / 80% RH). Was evaluated at 400 V under normal temperature and low humidity, 320 V under normal temperature and normal humidity, and 250 V under high temperature and high humidity.
[0132]
{Circle around (1)} The transfer efficiency was evaluated under a normal environment. In the evaluation method, first, a solid black image is formed on a photosensitive drum, the solid black image is collected with a transparent adhesive tape, and the image density (D1) is measured with a color reflection densitometer (Color reflection densitometer X-RITE 404A manufactured). by X-Rite Co.). Next, a solid black image is formed again on the photosensitive drum, the solid black image is transferred to a recording material, the solid black image transferred on the recording material is collected with a transparent adhesive tape, and its image density (D2 ) Was measured. The transfer efficiency was calculated from the obtained image densities (D1) and (D2) based on the following equation.
[0133]
Transfer efficiency (%) = (D2 / D1) × 100
[0134]
{Circle around (2)} The charge rising characteristics were evaluated by conducting a copy test on 1,000 sheets at normal temperature and low humidity, and evaluating the charge rising characteristics from the change in the charge amount of the developer from the beginning. The evaluation was performed after the idle rotation was performed for 3 minutes and then the image output was started. The charge amount at that time and the change width of the charge amount at the time of 1000 sheets were expressed in%, and were evaluated according to the following criteria.
[0135]
A: Change in charge amount is 0 to 10%
B: The change width of the charge amount is 11 to 20%
C: Change width of charge amount is 21 to 30%
D: Change width of charge amount is 31 to 40%
E: The change width of the charge amount is 41 to 50%
F: The change width of the charge amount is 51% or more.
[0136]
{Circle around (3)} The charge stability was evaluated by performing a copy test of 50,000 sheets under high temperature and high humidity, and evaluating the charge stability from the change in the charge amount of the developer. In the evaluation, the change amount of the charge amount at the time of copying 1000 sheets and the change amount of the charge amount at the end of the copy are expressed in%, and the evaluation was performed according to the following criteria.
[0137]
A: Change in charge amount is 0 to 10%
B: The change width of the charge amount is 11 to 20%
C: Change width of charge amount is 21 to 30%
D: Change width of charge amount is 31 to 40%
E: Change width of charge amount is 41 to 50%
F: The change width of the charge amount is 51% or more.
[0138]
{Circle around (4)} The toner is scattered by taking out the developing device after 50,000 sheets of anti-images have been taken out under high temperature and high humidity, and setting it in an idle rotating device. A4 paper was placed around the bottom of the sleeve of the developing device, and idle rotation was performed for 10 minutes. The weight of the toner dropped on the paper was measured, and evaluated according to the following criteria.
[0139]
A: 3 mg or less
B: 4-6 mg
C: 7-9 mg
D: 10-12 mg
E: 13-15 mg
F: 16mg or more
[0140]
{Circle around (5)} Regarding fog, the reflection density of blank paper and the density of the copying machine were measured under high temperature and high humidity (30 ° C./80% RH) using a densitometer TC6MC (Tokyo Denshoku Technical Center). The reflection density of the non-image portion of the paper was measured, and the difference between the two reflection densities was evaluated with reference to the reflection density of the white paper.
[0141]
A: 0.5% or less
B: 0.6-1.0%
C: 1.1 to 1.5%
D: 1.6 to 2.0%
E: 2.1 to 4.0%
F: 4.1% or more
[0142]
{Circle around (6)} The image density was measured at high temperature and high humidity by copying a solid black image at the initial stage and after completion of 30,000 copies, and measuring the density with a Macbeth densitometer.
[0143]
Table 5 shows the evaluation results.
[0144]
[Examples 2 to 17 and Comparative Examples 1 to 3]
An image was formed and evaluated in the same manner as in Example 1 except that the developers used were changed to the developers B to T. Table 5 shows the evaluation results.
[0145]
[Table 1]

[0146]
[Table 2]

[0147]
[Table 3]

[0148]
[Table 4]

[0149]
[Table 5]

[0150]
【The invention's effect】
As in the present invention, by using an appropriate amount of a specific azo-based iron compound and a metal oxycarboxylate compound in combination, an electrostatic image development that is excellent in transferability, has good chargeability in each environment, and can maintain high image quality for a long time. Can be obtained.
[Brief description of the drawings]
FIG. 1 is a relationship diagram between transfer efficiency and shape factor.
FIG. 2 is a diagram illustrating a relationship between a shape factor and lubricity.
FIG. 3 is a schematic explanatory view showing an example of an image forming apparatus that can suitably use the toner of the present invention.

Claims (35)

An electrostatic image developing toner having toner particles containing at least a binder resin, carbon black, an azo iron compound represented by the formula ( 2 ) and a metal oxycarboxylate compound,
A step of preparing a polymerizable monomer composition in which the toner particles contain a polymerizable monomer, carbon black, an azo-based iron compound represented by the formula ( 2 ), and a metal oxycarboxylate compound;
Dispersing the polymerizable monomer composition in an aqueous medium to form particles of the polymerizable monomer composition,
A toner for developing an electrostatic image, wherein the toner particles are produced through a process of polymerizing a polymerizable monomer in the particles to form a binder resin.
[Outside 1]

Wherein, _{R 1} and _{R 3} is a hydrogen _atom, an alkyl group of C _{1 ~ 18,} an alkenyl group of C _{2 ~ 18,} a sulfonamide group, a mesyl group, a sulfonic acid group, hydroxy _group, alkoxy C _{1 ~ 18} Group, acetylamino group, benzoylamino group, halogen atom and

Is an atom or a functional group selected from the group consisting of functional groups represented by R ₁ and R ₃ may be the same or different, and n and n ′ each represent an integer of 1 to 3, R _{5 represents} an alkyl group or an aryl group of _C 6 _{~ 18} of C _{1 ~ 18,}
R ₂ and R ₄ represent a hydrogen atom or a nitro group, and R ₂ and R ₄ may be the same or different;
X ₁ and _{X 2} are a hydrogen _atom, an alkyl group of C 1 _{~ 5,} an alkoxy group of C 1 _{~ 5,} represents an atom or a functional group selected from the group consisting of nitro groups and halogen atoms, and _{X 1} and _{X 2} May be the same or different, m and m 'represent an integer of 1 to 3,
A ⁺ represents an ion selected from the group consisting of a hydrogen ion, a sodium ion, a potassium ion, and an ammonium ion, or a mixture thereof. ] 2. The toner according to claim 1, wherein the metal oxycarboxylate is an aromatic metal oxycarboxylate. The toner according to claim 1, wherein the metal oxycarboxylate is a metal compound having aluminum or zinc. The oxycarboxylic acid metal compound is an alkyl salicylic acid aluminum compound and alkyl salicylic acid zinc compound having an alkyl group having 5 or less carbon atoms, from the group consisting of dialkyl salicylic acid aluminum compound and di-alkyl salicylic acid zinc compound having an alkyl group having 5 or less carbon atoms 2. The toner for developing an electrostatic image according to claim 1, which is selected from metal oxycarboxylate compounds. The electrostatic image development according to claim 1, wherein the metal oxycarboxylate compound is an aluminum 3,5-di-tert-butylsalicylate compound or a zinc 3,5- di- tert-butylsalicylate compound. For toner. The toner according to any one of claims 1 to 5, characterized in that said toner is non-magnetic toner. The binder resin, scan styrene - toner according to any one of claims 1 to 6, characterized in that an acrylic copolymer. The electrostatic image developing toner according to any one of claims 1 to 7 , wherein the toner particles have a polar resin. Polar resin, toner according to claim 8, characterized in that a polyester Le. The electrostatic image development according to any one of claims 1 to 9 , wherein the toner has a shape having a shape factor of SF-1 of 100 to 140 and SF-2 of 100 to 120. For toner. The toner has toner according to any one of claims 1 to 10, characterized in that it has a weight average particle size of 3 to 10 [mu] m. The electrostatic image developing toner according to any one of claims 1 to 10 , wherein the toner has a weight average particle diameter of 3 to 8 µm. The azo type iron compound, an electrostatic charge image developing toner according to any one of claims 1 to 12, characterized in that it is added from 0.1 to 8 parts by weight with respect to 100 parts by weight of the binder resin. The azo type iron compound, an electrostatic charge image developing toner according to any one of claims 1 to 12, characterized in that it is added from 0.1 to 6 parts by weight with respect to 100 parts by weight of the binder resin. The oxycarboxylic acid metal compound, 100 parts by weight of the binder resin, the toner for developing electrostatic images according to any one of claims 1 to 14, characterized in that it is added from 0.1 to 10 parts by weight . The electrostatic image development according to any one of claims 1 to 14 , wherein the metal oxycarboxylate is added in an amount of 0.1 to 6 parts by weight based on 100 parts by weight of the binder resin. toner. When the amount of the azo-based iron compound and the metal oxycarboxylate compound is A (parts by weight) and the amount of the oxycarboxylic acid metal compound is B (parts by weight), 0.1 ≦ a / B ≦ 20 the toner according to any one of claims 1 to 16, characterized in that added the to satisfy the relationship. Carbon black, toner according to any one of claims 1 to 17, characterized in that it is added from 1 to 20 parts by weight with respect to 100 parts by weight of the binder resin. At least the following steps,
i) a step of preparing a polymerizable monomer composition containing a polymerizable monomer, carbon black, an azo-based iron compound represented by the formula ( 2 ), and a metal oxycarboxylate compound;
ii) a step of dispersing the polymerizable monomer composition in an aqueous medium to produce particles of the polymerizable monomer composition;
iii) producing toner particles by polymerizing the polymerizable monomer in the particles,
A method for producing a toner for developing an electrostatic charge image having toner particles, comprising:
[Outside 3]

Wherein, _{R 1} and _{R 3} is a hydrogen _atom, an alkyl group of C _{1 ~ 18,} an alkenyl group of C _{2 ~ 18,} a sulfonamide group, a mesyl group, a sulfonic acid group, hydroxy _group, alkoxy C _{1 ~ 18} Group, acetylamino group, benzoylamino group, halogen atom and
[Outside 4]

Is an atom or a functional group selected from the group consisting of functional groups represented by R ₁ and R ₃ may be the same or different, and n and n ′ each represent an integer of 1 to 3, R _{5 represents} an alkyl group or an aryl group of _C 6 _{~ 18} of C _{1 ~ 18,}
R ₂ and R ₄ represent a hydrogen atom or a nitro group, and R ₂ and R ₄ may be the same or different;
X ₁ and _{X 2} are a hydrogen _atom, an alkyl group of C 1 _{~ 5,} an alkoxy group of C 1 _{~ 5,} represents an atom or a functional group selected from the group consisting of nitro groups and halogen atoms, and _{X 1} and _{X 2} May be the same or different, m and m 'represent an integer of 1 to 3,
A ⁺ represents an ion selected from the group consisting of a hydrogen ion, a sodium ion, a potassium ion, and an ammonium ion, or a mixture thereof. ] 20. The method according to claim 19 , wherein the metal oxycarboxylate is an aromatic metal oxycarboxylate. 20. The method according to claim 19 , wherein the metal oxycarboxylate is a metal compound having aluminum or zinc. The oxycarboxylic acid metal compound is an alkyl salicylic acid aluminum compound and alkyl salicylic acid zinc compound having an alkyl group having 5 or less carbon atoms, from the group consisting of dialkyl salicylic acid aluminum compound and di-alkyl salicylic acid zinc compound having an alkyl group having 5 or less carbon atoms 20. The method for producing a toner for developing electrostatic images according to claim 19 , wherein the metal oxycarboxylate is selected. The electrostatic image development according to claim 19 , wherein the metal oxycarboxylate is an aluminum 3,5-di-tert-butylsalicylate compound or a zinc 3,5-di-tert-butylsalicylate compound. Of manufacturing toner for toner. The toner manufacturing method of the electrostatic image developing toner according to any one of claims 19 to 23, characterized in that a non-magnetic toner. Polymerizable monomer composition, method for producing a toner according to any one of claims 19 to 24, characterized in that it contains a polar resin. Polar resin The production method of the toner according to claim 25, characterized in that the polyester Le. The toner has a shape factor SF-1 is 100 to 140, for developing an electrostatic charge image according to any one of claims 19 to 26 SF-2 is characterized in that it has a shape that is 100 to 120 Manufacturing method of toner. The method according to any one of claims 19 to 27 , wherein the toner has a weight average particle diameter of 3 to 10 µm. The method according to any one of claims 19 to 27 , wherein the toner has a weight average particle diameter of 3 to 8 µm. The azo type iron compound, toner according to any one of claims 19 to 29, characterized in that it is added from 0.1 to 8 parts by weight based on 100 parts by weight of the polymerizable monomer Manufacturing method. The azo type iron compound, toner according to any one of claims 19 to 29, characterized in that it is added from 0.1 to 6 parts by weight based on 100 parts by weight of the polymerizable monomer Manufacturing method. The electrostatic image development according to any one of claims 19 to 31 , wherein the metal oxycarboxylate is added in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the polymerizable monomer. Of producing toner for toner. The electrostatic image development according to any one of claims 19 to 31 , wherein the metal oxycarboxylate is added in an amount of 0.1 to 6 parts by weight based on 100 parts by weight of the polymerizable monomer. Of producing toner for toner. When the amount of the azo-based iron compound and the metal oxycarboxylate compound is A (parts by weight) and the amount of the oxycarboxylic acid metal compound is B (parts by weight), 0.1 ≦ The method for producing an electrostatic image developing toner according to any one of claims 19 to 33 , wherein the toner is added so as to satisfy the relationship of A / B ≤ 20. The carbon black method of producing a toner according to any one of claims 19 to 34, characterized in that it is added from 1 to 20 parts by weight based on 100 parts by weight of the polymerizable monomer.

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