JP2004245948A - Dry toner for electrostatic charge image, developer, and development apparatus using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide dry toner for an electrostatic charge image which stably controls and maintains the triboelectrostatic charge quantity of the toner, maintains its stability with less environmental variations, has excellent conveyance, development, transfer, storage properties, and does not generate an abnormal image. <P>SOLUTION: In the dry toner, a binder is made of a polyester, and the polyester does not contain a THF insoluble component and has a peak within an area of average molecular weight of 3-9×10<SP>3</SP>. A resin charge-controlling agent consists of a sulfonate group-containing monomer, an aromatic monomer having an electron attractive group, a (meth)acrylic ester monomer, and an aromatic vinyl monomer, and the agent also has the volume resistivity of 9.5-11.5 LogΩcm, and the content ratio of the components not more than average molecular weight of 1×10<SP>3</SP>is ≤10 wt%. The additive contains hydrophobic silica having specific particle diameter and surface-treated hydrophobic titanium oxide having 60-140 m<SP>2</SP>/g specific surface area, and has transmittance of 300 nm of ≥35% and transmittance of 600 nm of ≥80%. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【０１１５】
（ＩＩ）１次粒子径０．０１〜０．０３μｍで比表面積６０〜１４０ｍ^２／ｇの疎水化処理された酸化チタン
【０１１６】
合成例１
湿式法で作られた水可溶性成分が０．３５％含まれている一次平均粒径が０．０１５μｍの酸化チタン（テイカ社製ＭＴ−１５０Ａ）３００ｇを、イソブチルメトキシシラン３５ｇを溶解したトルエン溶液に添加し攪拌分散した。その後溶媒をドライアップしジェットミル粉砕し、カップリング剤処理酸化チタン（酸化チタンＩＩ−１）を得た。
【０１１７】
合成例２
湿式法で作られた水可溶性成分が０．３５％含まれている一次平均粒径が０．０１５μｍの酸化チタン（テイカ社製ＭＴ−１５０Ａ）３００ｇを、イソブチルメトキシシラン２５ｇを溶解したトルエン溶液に添加し攪拌分散した。その後溶媒をドライアップしジェットミル粉砕し、カップリング剤処理酸化チタン（酸化チタンＩＩ−２）を得た。
【０１１８】
合成例３
湿式法で作られた水可溶性成分が０．３５％含まれている一次平均粒径が０．０１５μｍの酸化チタン（テイカ社製ＭＴ−１５０Ａ）３００ｇを、メチルトリメトキシシラン３０ｇを溶解したトルエン溶液に添加し分散した。その後溶媒をドライアップしジェットミル粉砕し、カップリング剤処理酸化チタン（酸化チタンＩＩ−３）を得た。
【０１１９】
合成例４
湿式法で作られた水可溶性成分が０．３５％含まれている一次平均粒径が０．０１５μｍの酸化チタン（テイカ社製ＭＴ−１５０Ａ）３００ｇを、ｎ−ブチルトリメトキシシラン３０ｇを溶解したトルエン溶液に添加し分散した。その後溶媒をドライアップしジェットミル粉砕し、カップリング剤処理酸化チタン（酸化チタンＩＩ−３）を得た。
【０１２０】
得られた酸化チタンの特性値を表２に示す。
【０１２１】
【表２】

【０１２２】
実施例１
次の処方により着色材の処理を行った。
黄色系着色材処方：
ポリエステル樹脂Ａ １００重量部
Ｃ．Ｉ．ピグメントイエロー１８０ １００重量部
赤色系着色材処方：
ポリエステル樹脂Ａ １００重量部
Ｃ．Ｉ．ピグメントレッド１２２ １００重量部
青色系着色剤処方：
ポリエステル樹脂Ａ １００重量部
Ｃ．Ｉ．ピグメントブルー１５．３ １００重量部
黒色系着色剤処方：
ポリエステル樹脂Ａ １００重量部
カーボンブラック １００重量部
【０１２３】
各色ごとに上記材料をヘンシェルミキサーに入れ混合した後、混合物を空冷された２本ロールミルに投入し投入後１５分溶融混練した。その後混練物を圧延冷却し、ハンマーミルで粗粉砕しポリエステル樹脂処理着色材を得た。
次いで以下の処方によりトナーを作成した。
イエロートナー処方；
ポリエステル樹脂Ａ ９１重量部
ポリエステル樹脂Ａ処理黄色系着色材 １２重量部
樹脂帯電制御剤１ ３重量部
マゼンタトナー処方：
ポリエステル樹脂Ａ ９２重量部
ポリエステル樹脂Ａ処理赤色系着色材 １０重量部
樹脂帯電制御剤１ ３重量部
シアントナー処方：
ポリエステル樹脂Ａ ９４重量部
ポリエステル樹脂Ａ処理青色系着色材 ６重量部
樹脂帯電制御剤１ ３重量部
ブラックトナー処方：
ポリエステル樹脂Ａ ９０重量部
ポリエステル樹脂Ａ処理黒色系着色材 １２重量部
ポリエステル樹脂Ａ処理青色系着色材 ２重量部
樹脂帯電制御剤１ ３重量部
【０１２４】
各色ごとに上記材料をヘンシェルミキサーに入れ混合し、得られた混合物を１１０℃に加熱されたロールミルに投入し投入後３０分溶融混練した。その後混練物を冷却し、ハンマーミルで粗粉砕しエアージェットミル粉砕機で微粉砕した。さらに風力分級機により微粉を除去し各色トナーを得た。なおポリエステル樹脂Ａと樹脂帯電制御剤１のＴ_１／Ｔ_２は１．１６であった。
【０１２５】
得られた各色トナー１００重量部に対し次の添加剤をヘンシェルミキサーで混合し一成分現像剤とした。
Ｉ−２疎水性シリカ ２．５重量部
ＩＩ−１疎水性酸化チタン ０．８重量部
得られた一成分現像剤を市販のデジタルフルカラープリンター（リコー社製ＩＰＳｉＯ Ｃｏｌｏｒ ６５００）にセットし画像を形成した。得られた画像は鮮明であり地汚れなど異常は見られなかった。現像ローラーを目視で観察したところローラー上のトナー薄層は均一であった。現像ローラー上の帯電量を吸引法により測定したところ、イエロー現像剤は−３５μＣ／ｇ、マゼンタ現像剤は−３０μＣ／ｇ、シアン現像剤は−３１μＣ／ｇ、ブラック現像剤は−３２μＣ／ｇであった。２７℃８０％ＲＨの高温高湿条件下、１０℃１５％ＲＨの低温低湿条件下で同様に作像したが、変化は見られず良好な画像が形成された。常温、低温低湿、高温高湿、常温と連続して各環境下でフルカラー画像による合計４万枚までの耐久性試験を行ったところ、定着画像に著しい変化は見られず、４万枚目の画像も地汚れもなく鮮明な画像であった。現像ローラーを目視で観察したところ、ローラー上のトナー薄層に著しい変化は見られず、この時の現像剤の帯電量はイエロー現像剤−３１μＣ／ｇ、マゼンタ現像剤−２９μＣ／ｇ、シアン現像剤−２９μＣ／ｇ、ブラック現像剤−２７μＣ／ｇと安定していた。現像ローラー、ブレード、感光体を目視観察したがフィルミングは見られなかった。
【０１２６】
実施例２
次の処方により着色材の処理を行った。
黄色系着色材処方：
ポリエステル樹脂Ｃ １００重量部
Ｃ．Ｉ．ピグメントイエロー１８０ １００重量部
赤色系着色材処方：
ポリエステル樹脂Ｃ １００重量部
Ｃ．Ｉ．ピグメントレッド１４６ １００重量部
青色系着色剤処方：
ポリエステル樹脂Ｃ １００重量部
Ｃ．Ｉ．ピグメントブルー１５．３ １００重量部
黒色系着色剤処方：
ポリエステル樹脂Ｃ １００重量部
カーボンブラック １００重量部
【０１２７】
各色ごとに上記材料をヘンシェルミキサーに入れ混合した後、混合物を空冷された２本ロールミルに投入し投入後１５分溶融混練した。その後混練物を圧延冷却し、ハンマーミルで粗粉砕しポリエステル樹脂処理着色材を得た。
次いで以下の処方によりトナーを作成した。
イエロートナー処方；
ポリエステル樹脂Ｃ ９１重量部
ポリエステル樹脂Ｃ処理黄色系着色材 １２重量部
樹脂帯電制御剤４ ３重量部
マゼンタトナー処方：
ポリエステル樹脂Ｃ ９２重量部
ポリエステル樹脂Ｃ処理赤色系着色材 １０重量部
樹脂帯電制御剤４ ３重量部
シアントナー処方：
ポリエステル樹脂Ｃ ９４重量部
ポリエステル樹脂Ｃ処理青色系着色材 ６重量部
樹脂帯電制御剤４ ３重量部
ブラックトナー処方：
ポリエステル樹脂Ｃ ９０重量部
ポリエステル樹脂Ｃ樹脂処理黒色系着色材 １２重量部
ポリエステル樹脂Ｃ樹脂処理青色系着色材 ２重量部
樹脂帯電制御剤４ ３重量部
【０１２８】
各色ごとに上記材料をヘンシェルミキサーに入れ混合し、得られた混合物を８０℃に加熱された２軸連続混練機に投入し溶融混練した。その後混練物を冷却し、ハンマーミルで粗粉砕し気流式粉砕機で微粉砕した。さらに風力分級機により微粉を除去し各色トナーを得た。なおポリエステル樹脂Ｃと樹脂帯電制御剤４のＴ_１／Ｔ_２は１．１１であった。得られた各色トナー１００重量部に対し次の添加剤をヘンシェルミキサーで混合した。
Ｉ−３疎水性シリカ ２．１重量部
ＩＩ−４疎水性酸化チタン １．０重量部
得られたトナー６重量部とシリコン樹脂コートキャリア９４部を混合し二成分現像剤とした。得られたニ成分現像剤を市販のデジタルフルカラープリンター（リコー製ＩＰＳｉＯ Ｃｏｌｏｒ ７１００）にセットし画像を形成した。得られた画像は地汚れも無く鮮明であった。高温高湿、低温低湿での画像、帯電共に異常は見られなかった。フルカラー画像による１万枚までの耐久性試験を行っても異常画像は見られず、試験後機内を観察したが飛散等は見られず、感光体への付着等もなかった。
【０１２９】
比較例１
（酸化チタンの処理）
湿式法で作られた水可溶性成分が０．３５％含まれている酸化チタン（テイカ社製ＭＴ−１５０Ａ）を水洗し、水可溶性成分が０．１５％の酸化チタンを得た。この酸化チタン３００ｇを、イソブチルトリメトキシシラン３５ｇを溶解したトルエン溶液に添加し分散した。その後溶媒をドライアップしジェットミル微粉砕し更にピンミルにより高分散を行い、カップリング剤処理酸化チタン（疎水性酸化チタンＩＩ−５）を得た。得られた表面処理酸化チタンの吸光度を測定したところ、３００ｎｍでの透過率が２１％、６００ｎｍでの透過率が９７％であった。
【０１３０】
次に実施例１で得られた各色トナー１００重量部に対し、次の添加剤を混合し一成分現像剤とした。
Ｉ−２疎水性シリカ ２．４重量部
ＩＩ−５疎水性酸化チタン ０．６重量部
得られた一成分現像剤を市販のデジタルフルカラープリンター（リコー社製ＩＰＳｉＯ Ｃｏｌｏｒ ６５００）にセットし画像を形成した。得られた画像は鮮明であり地汚れなど異常は見られなかった。現像ローラーを目視で観察したところローラー上のトナー薄層は均一であった。現像ローラー上の帯電量を吸引法により測定したところ、イエロー現像剤は−４３μＣ／ｇ、マゼンタ現像剤は−３６μＣ／ｇ、シアン現像剤は−３８μＣ／ｇ、ブラック現像剤は−３５μＣ／ｇであった。２７℃８０％ＲＨの高温高湿条件下で画像を形成したところ、ぼそつきのある画像になってしまった。また１０℃１５％ＲＨの低温低湿条件下で同様に作像したところ、ＩＤの低いかすれた画像が得られた。常温、低温低湿、高温高湿、常温と連続して各環境下でフルカラー画像による耐久性試験を行ったところ、地汚れ、チリ、画像上にスジなどの異常が発生した。この時点で現像ローラーを目視で観察したところ、ローラー上のトナー薄層に周方向にスジが発生していた。現像剤の帯電量を測定したところイエロー現像剤−２８μＣ／ｇ、マゼンタ現像剤−２２μＣ／ｇ、シアン現像剤−２５μＣ／ｇ、ブラック現像剤−２１μＣ／ｇと劣化していた。
【０１３１】
【発明の効果】
以上説明したように、請求項１によれば、少なくともバインダー樹脂、着色材、帯電制御剤及び添加剤を主成分とする乾式静電荷像現像用トナーにおいて、該バインダー樹脂が１種類以上のポリエステル樹脂からなり、該ポリエステル樹脂はＴＨＦ不溶成分を含まず、かつゲルパーミエーションクロマトグラフィーにおける分子量分布において、分子量５×１０^２以下の成分の含有割合が４重量％以下であり、重量分子量３×１０^３〜９×１０^３の領域にメインのピークを有し、前記帯電制御剤は樹脂帯電制御剤からなり、該樹脂帯電制御剤は単量体として少なくとも（Ａ）スルホン酸塩基含有モノマー、（Ｂ）電子吸引基を有する芳香族モノマー、（Ｃ）アクリル酸エステルモノマー及び／またはメタアクリル酸エステルモノマー、（Ｄ）芳香族ビニルモノマーのうち、（Ａ）〜（Ｃ）または（Ａ）〜（Ｄ）を構成単位とし、該樹脂帯電制御剤の体積抵抗が９．５〜１１．５ＬｏｇΩ・ｃｍであり、該樹脂帯電制御剤において重量平均分子量１×１０^３以下の成分の含有割合が１０重量％以下であり、前記添加剤は１次粒子径０．０１〜０．０３μｍの疎水化処理されたシリカと、１次粒子径０．０１〜０．０３μｍで比表面積６０〜１４０ｍ^２／ｇの疎水化処理された酸化チタンとを含み、該酸化チタンは湿式法により製造された水可溶性成分量が０．２重量％以上ある酸化チタン微粒子を表面処理したもので、ＵＶ吸光法において３００ｎｍの透過率が３５％以上、かつ６００ｎｍの透過率が８０％以上であることを特徴とする乾式静電荷像現像用トナーにより、ＴＨＦ不溶分の分散析出に伴う光沢性の低下が防止され、重量平均分子量と数平均分子量の比を規定することによりブレード、スリーブなどへのフィルミングの発生を防ぎ、ゲルパーミエーションクロマトグラフィーにおける分子量分布を規制することで、長期間使用時のブレード、スリーブの汚染、フィルミングの発生を抑制し、樹脂帯電制御剤の体積抵抗を規定することにより、地汚れやトナー飛散が無く画像にスジ、ムラの発生が無い安定した画像が得られ、樹脂帯電制御剤の重量平均分子の規定により、制御剤のトナー中の分散がよくなり生産工程不具合を無くすことができ、さらに定着性、発色性を良くでき、添加剤に特定のシリカと酸化チタンを前記ポリエステル、帯電制御剤と共に用いることにより、帯電性の安定したトナーを得ることができる。
【０１３２】
請求項２によれば、前記バインダー樹脂のＤＳＣにおける吸熱ピークが６０〜７０℃の範囲にあることを特徴とする請求項１に記載の乾式静電荷像現像用トナーにより、保存性、トナー生産性の良好なトナーを得ることが可能となる。
【０１３３】
請求項３によれば、前記バインダー樹脂の重量平均分子量（Ｍｗ）と数平均分子量（Ｍｎ）の比が２≦Ｍｗ／Ｍｎ≦１０であることを特徴とする請求項１または２に記載の乾式静電荷像現像用トナーにより、光沢の良い高品質の画像が得られ、製造時の生産性が良く、画像形成時に長期間使用してもスリーブ汚染、フィルミングの発生を抑制することが可能となる。
【０１３４】
請求項４によれば、前記バインダー樹脂の酸価が１０ＫＯＨｍｇ／ｇ以下であることを特徴とする請求項１から３のいずれか一項に記載の乾式静電荷像現像用トナーにより、環境変化による画像劣化を防ぐことが可能となる。
【０１３５】
請求項５によれば、前記バインダー樹脂のフローテスターによる見掛け粘度が１０^３Ｐａ・ｓとなる温度が９５〜１２０℃であることを特徴とする請求項１から４のいずれか一項に記載の乾式静電荷像現像用トナーにより、ホットオフセットが起り難く、光沢の良好な画像を得ることが可能となる。
【０１３６】
請求項６によれば、前記樹脂帯電制御剤の（Ａ）スルホン酸塩基含有モノマーの繰り返し単位が樹脂帯電制御剤重量に対して１〜３０重量％、前記樹脂帯電制御剤の（Ｂ）電子吸引基を有する芳香族モノマーの繰り返し単位が樹脂帯電制御剤重量に対して１〜８０重量％、前記樹脂帯電制御剤の（Ｃ）アクリル酸エステルモノマー及び／またはメタアクリル酸エステルモノマーの繰り返し単位が樹脂帯電制御剤重量に対して１０〜８０重量％、前記樹脂帯電制御剤の（Ｄ）芳香族ビニルモノマーの繰り返し単位が樹脂帯電制御剤重量に対して０〜３０重量％の割合で含まれることを特徴とする請求項１から５のいずれか一項に記載の乾式静電荷像現像用トナーにより、帯電立ち上がり性能、飽和帯電量が十分で、温湿度変化に対抗でき、スリーブ汚染、感光体フィルミングの発生を防ぎ、製造時生産性の低下を防ぐことが可能となる。
【０１３７】
請求項７によれば、前記樹脂帯電制御剤の（Ｂ）電子吸引基を有する芳香族モノマーが、塩素原子または、ニトロ基により置換されたフェニルマレイミド置換体またはフェニルイタコンイミド置換体であることを特徴とする請求項１から６のいずれか一項に記載の乾式静電荷像現像用トナーによれば、帯電性や耐フィルミング性の良好なトナーを得ることが可能となる。
【０１３８】
請求項８によれば、前記樹脂帯電制御剤のフローテスターによる見掛け粘度が１０^４Ｐａ・ｓとなる温度が８５〜１１０℃であることを特徴とする請求項１から７のいずれか一項に記載の乾式静電荷像現像用トナーによれば、帯電制御剤の分散性が良く、トナーの貯蔵安定性も良好で、製造時の粉砕工程での固着がなく、地汚れ、トナー飛散が無く、カラートナー色重ね時の発色性の良いトナーを得ることが可能となる。
【０１３９】
請求項９によれば、前記樹脂帯電制御剤の重量平均分子量が５×１０^３〜１×１０^５であることを特徴とする請求項１から８のいずれか一項に記載の乾式静電荷像現像用トナーによれば、帯電制御剤がトナー中に適度に分散され、帯電が低下せず、画像の地汚れ、トナー飛散が無く、トナーの定着性、発色性を良好にすることが可能となる。
【０１４０】
請求項１０によれば、前記樹脂帯電制御剤をトナー粒子に対して、０．１〜２０重量％含有することを特徴とする請求項１から９のいずれか一項に記載の乾式静電荷像現像用トナーにより、帯電の立ち上がりや、帯電が十分で、画像の地汚れ、トナー飛散が無いトナーを得ることが可能となる。
【０１４１】
請求項１１によれば、前記バインダー樹脂のフローテスターによる見掛け粘度が１０^３Ｐａ・ｓとなる温度をＴ_１、前記樹脂帯電制御剤のフローテスターによる見掛け粘度が１０^４Ｐａ・ｓとなる温度をＴ_２としたとき、Ｔ_１、Ｔ_２が０．９＜Ｔ_１／Ｔ_２＜１．４であることを特徴とする請求項１から１０のいずれか一項に記載の乾式静電荷像現像用トナーによれば、トナーの良好な帯電性とフィルミング発生防止性を得ることが可能となる。
【０１４２】
請求項１２によれば、前記添加剤が母体トナー１００重量部に対し、１次粒子径０．０１〜０．０３μｍの疎水化処理されたシリカを２．１重量部以上、１次粒子径０．０１〜０．０３μｍで比表面積６０〜１４０ｍ^２／ｇの疎水化処理された酸化チタンを０．４〜１．０重量部含むことを特徴とする請求項１から１１のいずれか一項に記載の乾式静電荷像現像用トナーにより、トナーの帯電性が適度となり、トナー飛散、地汚れを防止することが可能となる。
【０１４３】
請求項１３によれば、請求項１に記載の乾式静電荷像現像用トナーからなることを特徴とする乾式一成分現像剤により、トナーの摩擦帯電量を安定的に制御、維持することができ、かつ環境変動も少なく安定した摩擦帯電性を維持することができ、またトナーの搬送性、現像性、転写性、保存性に優れ、感光体への付着による異常画像が発生しない乾式一成分現像剤を得ることが可能となる。
【０１４４】
請求項１４によれば、請求項１に記載の乾式静電荷像現像用トナーとキャリアからなることを特徴とする乾式二成分現像剤により、トナーの摩擦帯電量を安定的に制御、維持することができ、かつ環境変動も少なく安定した摩擦帯電性を維持することができ、またトナーの搬送性、現像性、転写性、保存性に優れ、感光体への付着による異常画像が発生しない乾式二成分現像剤を得ることが可能となる。
【０１４５】
請求項１５によれば、潜像保持体上に潜像を形成する潜像形成工程、該潜像を現像剤担持体上の現像剤を用いて現像する現像工程、現像されたトナー像を転写体上に転写する転写工程、転写体上のトナー像を加熱定着する定着工程、を有する画像形成方法において、現像剤として請求項１３に記載の乾式一成分現像剤を用いることを特徴とする画像形成方法により、トナーの摩擦帯電量を安定的に制御、維持することができ、かつ環境変動も少なく安定した摩擦帯電性を維持でき、トナーの搬送性、現像性、転写性、定着性、保存性に優れ、地汚れのない色鮮やかな画像が得ることが可能となる。
【０１４６】
請求項１６によれば、請求項１３に記載の一成分現像剤を保持する容器、該現像剤を補給する容器、前記潜像形成工程を有する装置、前記現像工程を有する装置、前記転写工程を有する装置、前記定着工程を有する装置を持つことを特徴とする画像形成装置により、トナーの摩擦帯電量を安定的に制御、維持することができ、かつ環境変動も少なく安定した摩擦帯電性を維持することができ、またトナーの搬送性、現像性、転写性、保存性に優れ、感光体への付着による異常画像が発生しない画像形成が可能となる。
【０１４７】
請求項１７によれば、潜像保持体上に潜像を形成する潜像形成工程、該潜像を現像剤担持体上の現像剤を用いて現像する現像工程、現像されたトナー像を転写体上に転写する転写工程、転写体上のトナー像を加熱定着する定着工程、を有する画像形成方法において、現像剤として請求項１４に記載の乾式二成分現像剤を用いることを特徴とする画像形成方法により、トナーの摩擦帯電量を安定的に制御、維持することができ、かつ環境変動も少なく安定した摩擦帯電性を維持することができ、またトナーの搬送性、現像性、転写性、保存性に優れ、感光体への付着による異常画像が発生しない画像形成が可能となる。
【０１４８】
請求項１８によれば、請求項１４に記載の乾式二成分現像剤を保持する容器、該トナーを補給する容器、前記潜像形成工程を有する装置、前記現像工程を有する装置、前記転写工程を有する装置、前記定着工程を有する装置を持つことを特徴とする画像形成装置により、トナーの摩擦帯電量を安定的に制御、維持することができ、かつ環境変動も少なく安定した摩擦帯電性を維持することができ、またトナーの搬送性、現像性、転写性、保存性に優れ、感光体への付着による異常画像が発生しない画像形成が可能となる。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a toner used as a developer for developing an electrostatic image in electrophotography, electrostatic recording, electrostatic printing, and the like, and an electrostatic image developing apparatus using the toner. Toner having stable chargeability and image forming property by resin, charge control agent, and additive, copying machine using the toner, full-color copying machine using indirect electrophotographic multicolor image development system, full-color laser printer, and full-color The present invention relates to an electrostatic image developing device.
[0002]
[Prior art]
In the developing step, a developer used in electrophotography, electrostatic recording, electrostatic printing, and the like is once attached to an image carrier such as a photoconductor on which an electrostatic image is formed, and then is transferred in a transfer step. After being transferred from the photoconductor to a transfer medium such as transfer paper, it is fixed on the paper surface in a fixing step. At this time, as a developer for developing an electrostatic image formed on the latent image holding surface, a two-component developer composed of a carrier and a toner and a one-component developer (a magnetic toner, Non-magnetic toner) is known. In the two-component developing method, the developer deteriorates due to toner particles adhering to the carrier surface, and since only the toner is consumed, the toner concentration in the developer decreases. The developing device is relatively large. On the other hand, in the one-component developing system, the size of the device has been further reduced due to the enhancement of functions of the developing roller and the like.
[0003]
In recent years, office automation and colorization in offices have been further advanced, and not only copying of originals consisting only of conventional characters but also graphs created by personal computers, images taken by digital cameras, pictorial images read from scanners, etc. There is an increasing opportunity to output manuscripts and the like by a printer and copy many sheets as presentation materials. In a printer output image, a complex configuration such as a solid image, a line image, and a halftone image is mixed in one document, and a demand for high reliability as well as a demand for high reliability of the image is increasing.
[0004]
Conventional electrophotographic processes using a one-component developer are classified into a magnetic one-component developing method using a magnetic toner and a non-magnetic one-component developing method using a non-magnetic toner.
The magnetic one-component developing method uses a developer carrying member provided with a magnetic field generating means such as a magnet inside to hold a magnetic toner containing a magnetic substance such as magnetite, and make the layer thinner by a layer thickness regulating member to perform development. In recent years, a large number of such printers have been put to practical use. However, the magnetic material has a disadvantage that it is colored, and most of it is black, and it is difficult to colorize the magnetic material.
[0005]
On the other hand, in the non-magnetic one-component developing method, since the toner has no magnetic force, a toner supply roller or the like is pressed against the developer carrier to supply the toner onto the developer carrier and electrostatically hold the toner. The development is performed by reducing the thickness by a thickness regulating member. This has the advantage of being able to cope with colorization because it does not contain a colored magnetic material.Furthermore, since a magnet is not used for the developer carrier, it is possible to further reduce the weight and cost of the apparatus, and in recent years a small full-color printer It has been put to practical use.
[0006]
On the other hand, in the two-component developing method, a carrier is used as a means for charging and transporting the toner. The toner and the carrier are sufficiently stirred and mixed in the developing device, and then transported to the developer carrier to be developed. It is possible to maintain stable chargeability and transportability even in the use of, and it is easy to cope with a high-speed developing device.
[0007]
On the other hand, in the present situation, there are still many problems to be improved in the one-component developing system. In the one-component developing method, since there is no stable charging or transporting means such as a carrier, charging failure and transport failure are likely to occur due to long-time use and high speed. That is, in the one-component developing method, after the toner is conveyed onto the developer carrying member, the toner is thinned and developed by the layer thickness regulating member, but the friction between the toner and the developer carrying member, the layer thickness regulating member, etc. Since the contact time with the charging member and the frictional charging time are very short, the amount of low-charge and reverse-charge toner tends to increase more than in the two-component developing method using a carrier.
[0008]
In particular, in a non-magnetic one-component developing method, means for transporting toner (developer) by at least one toner transport member and developing an electrostatic latent image formed on the latent image carrier by the transported toner is usually used. In this case, the thickness of the toner layer on the surface of the toner conveying member must be reduced as much as possible. This is true even when a two-component developer having a very small carrier diameter is used, and particularly when a one-component developer is used and its toner has a high electric resistance. Since the toner must be charged by the developing device, the layer thickness of the toner must be significantly reduced. This is because if the toner layer is thick, only the surface of the toner layer is charged, and it is difficult to uniformly charge the entire toner layer. For this reason, the toner is required to maintain a faster charging speed and an appropriate amount of charge.
[0009]
Therefore, conventionally, a charge control agent or an additive is added to stabilize the charge of the toner. The charge control agent functions to control the frictional charge amount of the toner and maintain the frictional charge amount. Typical charge control agents of negative charge include monoazo dyes, salicylic acid, naphthoic acid, metal salts and complex salts of dicarboxylic acids, diazo compounds, complex compounds with boron, and the like. Examples of the charge control agent include a quaternary ammonium salt compound, an imidazole compound, nigrosine, and an azine dye.
[0010]
However, some of these charge control agents have a chromatic color, and many of them cannot be used for color toners. In addition, among these charge control agents, due to poor compatibility with the binder resin, those present on the toner surface that are greatly involved in charging are easily detached, causing variations in toner charging, and There is a disadvantage that contamination of the developing sleeve and filming of the photoconductor are easily caused.
[0011]
Therefore, in the related art, although a good image is obtained in the initial stage, the image quality gradually changes, and a phenomenon occurs in which background smearing and blurring occur. In particular, when applied to color copying and used continuously while replenishing the toner, the charge amount of the toner decreases and the color tone of the initial copied image becomes remarkably different. There is a disadvantage that the image forming unit called a process cartridge must be replaced at an early stage just after copying to a certain extent. As a result, the burden on the environment was great and the user had to take time. Furthermore, since many of these cartridges contain heavy metals such as chromium, they have recently become a problem in terms of safety.
[0012]
In order to solve the above-mentioned problem, a resin charge control agent having improved compatibility with a binder resin, transparency of a toner-fixed image, and safety has been known. Since these resin charge control agents have good compatibility with the binder resin, they are excellent in stable chargeability and transparency. However, these resin charge control agents have the disadvantage that the charge amount and the charge speed are inferior to toners using a monoazo dye, a metal salt or a metal complex salt of salicylic acid, naphthoic acid, or dicarboxylic acid. In addition, although the chargeability is improved by increasing the amount of the resin charge control agent, the toner fixability (low-temperature fixability, anti-offset property) is adversely affected. Further, these compounds have high environmental stability (humidity resistance) of the charge amount. For this reason, there is also a problem that background soiling (fogging) easily occurs. (For example, refer to Patent Documents 1 to 4)
[0013]
Therefore, a copolymer of a monomer containing an organic acid salt such as a sulfonate group and an aromatic monomer having an electron withdrawing group has been proposed. However, a sufficient amount of charge is ensured due to hygroscopicity and adhesiveness, which are considered to be caused by monomers containing organic acid salts such as sulfonate groups.However, the toner is not sufficiently dispersed in the binder resin, and the toner is charged for a long time. The effect of suppressing variations in the image quality and preventing filming on the developing sleeve and the photoconductor is not sufficient. (For example, see Patent Documents 5 to 8)
[0014]
Further, in order to further improve the compatibility with a styrene-based resin or a polyester-based resin as a binder resin, a monomer containing an organic acid salt such as a sulfonate group, an aromatic monomer having an electron-withdrawing group, and a styrene-based monomer or polyester, respectively. Copolymers with a system monomer have also been proposed, but the effect of maintaining the charge amount over a long period of time and preventing the developing sleeve and the photoconductor from filming is insufficient. In particular, a binder resin for a full-color toner is insufficient for a polyester resin or a polyol resin, which is suitable in terms of color development and image strength.
[0015]
In recent years, the demand for printers has expanded, and the miniaturization, high speed, and low cost of the equipment have been progressing, and higher reliability and longer life have been demanded for the equipment.Toners must also be able to maintain various characteristics for a long time. However, these resin charge control agents cannot maintain the charge control effect, and contaminate the developing sleeve and the layer thickness regulating members (blades and rollers) to lower the toner charging performance and cause photoreceptor filming. There was a problem.
[0016]
In addition, the process of developing in a short time with a small amount of developer is achieved by downsizing and speeding up, and a developer having better charge rising property is required. Regarding development, various development methods have been proposed for both two-component developers and one-component developers.However, non-magnetic one-component development that does not require a carrier is excellent because it can be made smaller and lighter, and is used for printers. Is preferred. In this developing method, since the replenishing property of the toner to the developing roller and the toner holding property of the developing roller are poor, the toner is forcibly rubbed against the developing roller or the amount of toner on the developing roller is regulated by a blade. As a result, the toner tends to be filmed on the developing roller, causing a problem that the life of the developing roller is shortened and the charge amount of the toner becomes unstable. This also prevents good development. Therefore, in a color toner for non-magnetic one-component development, in addition to the characteristics required for a general color toner, the heat resistance of a binder resin used for the toner is often inferior. Filming and the like are likely to occur.
[0017]
In addition, the additive has functions of controlling and maintaining the triboelectric charge amount of the toner, as well as functions of transporting, developing, transferring, and storing the toner. It is disclosed that hydrophobic silica is added to the toner in order to improve these characteristics. However, if the silica alone is used, the chargeability is too high, and the transferability is too good, which causes defects such as dust and scattering. I do. (For example, see Patent Documents 9 and 10)
[0018]
In addition, it is disclosed that titanium oxide or titanium oxide surface-treated with a coupling agent is added to the toner, but sufficient chargeability and fluidity cannot be obtained with titanium oxide alone, or the particle size is large. Further, since secondary aggregation is likely to occur, the toner is not uniformly attached to the toner, which causes an abnormal image. (For example, see Patent Documents 11 and 12)
[0019]
In addition, although a fine particle titanium oxide having a surface treatment is disclosed, although the dispersibility of the particles is improved, a sufficient charge amount has not yet been obtained by itself. When this titanium oxide is used in combination with silica, on the contrary, the charge amount increases with time. (For example, see Patent Document 13)
[0020]
Furthermore, it is disclosed that hydrophobic silica and hydrophobic titanium oxide are used together, but the combination of additives having high hydrophobicity causes an increase in the amount of charge over time, which causes a transfer failure and the like. It becomes. (For example, see Patent Documents 14 and 15)
[0021]
[Patent Document 1]
JP-A-63-88564
[Patent Document 2]
JP-A-63-184762
[Patent Document 3]
JP-A-3-56974
[Patent Document 4]
JP-A-6-230609
[Patent Document 5]
JP-A-8-30017
[Patent Document 6]
JP-A-9-171271
[Patent Document 7]
JP-A-9-212896
[Patent Document 8]
JP-A-11-218965
[Patent Document 9]
JP-A-56-128957
[Patent Document 10]
JP-A-59-52255
[Patent Document 11]
JP-A-60-112052
[Patent Document 12]
JP-A-4-40467
[Patent Document 13]
Japanese Patent No. 3232858
[Patent Document 14]
JP-A-7-43930
[Patent Document 15]
Japanese Patent No. 3160688
[0022]
[Problems to be solved by the invention]
However, in the above-mentioned prior arts, in the examples described in Patent Documents 1 to 4, there is a drawback that the charge amount and the charge speed are inferior. To prevent this, the chargeability is improved by increasing the addition amount of the resin charge control agent. However, it has an adverse effect on the toner fixability (low-temperature fixability and anti-offset property). Further, these compounds have high environmental stability of charge amount (humidity resistance), but have a problem that background stain (fogging) easily occurs.
[0023]
Further, in the examples of Patent Documents 5 to 8, although a sufficient charge amount is secured by hygroscopicity and adhesiveness, dispersion in a binder resin is not sufficient, thereby suppressing variation in charge and filling a sleeve or a photoreceptor. There is a problem in that the effect of preventing the occurrence of the heading and the like is not sufficient.
[0024]
In the examples of Patent Documents 9 and 10, the chargeability of silica alone is too high, and the transferability is too good, so that defects such as dust and scattering occur.
[0025]
In the examples of Patent Documents 11 and 12, titanium oxide alone does not provide sufficient chargeability and fluidity, or has a large particle diameter and is easily aggregated secondaryly. It becomes.
[0026]
In the example of Patent Document 13, although the dispersibility of the particles is improved, a sufficient charge amount has not yet been obtained by itself. When this titanium oxide is used in combination with silica, on the contrary, the charge amount increases with time.
[0027]
In the examples of Patent Documents 14 and 15, the charge amount increases with time due to the combination of additives having high hydrophobicity, which causes transfer failure and the like. As described above, the techniques described in the conventional patent documents have various problems.
[0028]
Therefore, the present invention has been made to solve the above problems, and it is possible to stably control and maintain the triboelectric charge amount of toner, and to maintain stable triboelectric chargeability with little environmental fluctuation. The present invention provides a dry electrostatic image developing toner and a developer, and a developing device using the same, which is excellent in toner transportability, developability, transferability, and storage stability, and does not cause abnormal images due to adhesion to a photoreceptor. The purpose is to do.
[0029]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, in the invention according to claim 1, in a toner for developing a dry electrostatic image mainly containing at least a binder resin, a colorant, a charge control agent and an additive, one kind of the binder resin is used. The polyester resin contains the above-mentioned polyester resin, does not contain a THF-insoluble component, and has a molecular weight of 5 × 10 5 in a molecular weight distribution by gel permeation chromatography.²The content of the following components is 4% by weight or less, and the weight molecular weight is 3 × 10³~ 9 × 10³Wherein the charge control agent comprises a resin charge control agent, and the resin charge control agent has at least (A) a sulfonate group-containing monomer and (B) an electron withdrawing group as monomers. Among the aromatic monomer, (C) an acrylate monomer and / or a methacrylate monomer, and (D) an aromatic vinyl monomer, (A) to (C) or (A) to (D) are constituent units; The volume resistance of the resin charge control agent is 9.5 to 11.5 Log Ω · cm, and the weight average molecular weight of the resin charge control agent is 1 × 10³The content of the following components is 10% by weight or less, and the additive has a hydrophobic particle-treated silica having a primary particle diameter of 0.01 to 0.03 μm and a primary particle diameter of 0.01 to 0.03 μm. Specific surface area 60-140m²/ G of titanium oxide subjected to hydrophobizing treatment, wherein the titanium oxide is obtained by subjecting titanium oxide fine particles having a water-soluble component content of 0.2% by weight or more produced by a wet method to a surface treatment. The most important feature is a dry electrostatic image developing toner having a transmittance of 300 nm or more at 35% or more and a transmittance of 600 nm at 80% or more.
[0030]
The invention according to claim 2 is characterized mainly by the toner for developing a dry electrostatic image according to claim 1, wherein the endothermic peak in DSC of the binder resin is in the range of 60 to 70 ° C.
[0031]
In the third aspect of the present invention, the dry electrostatic image development according to the first or second aspect, wherein a ratio of a weight average molecular weight (Mw) to a number average molecular weight (Mn) of the binder resin is 2 ≦ Mw / Mn ≦ 10. The main feature is the toner for use.
[0032]
According to a fourth aspect of the present invention, the toner for developing a dry electrostatic image according to any one of the first to third aspects is characterized in that the binder resin has an acid value of 10 KOHmg / g or less.
[0033]
In the invention according to claim 5, the apparent viscosity of the binder resin measured by a flow tester is 10%.³The toner for developing a dry electrostatic charge image according to any one of claims 1 to 4, wherein the temperature at which Pa · s is 95 to 120 ° C is a main feature.
[0034]
In the invention according to the sixth aspect, the repeating unit of the (A) sulfonic acid group-containing monomer of the resin charge control agent is 1 to 30% by weight based on the weight of the resin charge control agent, and the (B) electron The repeating unit of the aromatic monomer having an attraction group is 1 to 80% by weight based on the weight of the resin charge control agent, and the repeating unit of the (C) acrylate monomer and / or methacrylate ester monomer of the resin charge control agent is 10 to 80% by weight based on the weight of the resin charge control agent, and the repeating unit of the aromatic vinyl monomer (D) of the resin charge control agent is contained at a ratio of 0 to 30% by weight based on the weight of the resin charge control agent. Item 6. The toner for developing a dry electrostatic image according to any one of items 1 to 5 is a main feature.
[0035]
In the invention described in claim 7, the (B) aromatic monomer having an electron-withdrawing group of the resin charge control agent is a phenylmaleimide-substituted or phenylitaconimide-substituted compound substituted by a chlorine atom or a nitro group. Item 7 is a toner for developing a dry electrostatic image according to any one of Items 1 to 6.
[0036]
In the invention according to claim 8, the apparent viscosity of the resin charge control agent measured by a flow tester is 10%.⁴The toner for developing a dry electrostatic image according to any one of claims 1 to 7, wherein the temperature at which Pa · s is 85 to 110 ° C is a main feature.
[0037]
In the invention according to claim 9, the weight average molecular weight of the resin charge control agent is 5 × 10 5³~ 1 × 10⁵The toner for developing a dry electrostatic image according to any one of claims 1 to 8, which is a main feature.
[0038]
According to a tenth aspect of the present invention, there is provided the dry electrostatic image developing toner according to any one of the first to ninth aspects, wherein the resin charge control agent is contained in an amount of 0.1 to 20% by weight based on the toner particles. Main features.
[0039]
In the invention according to claim 11, the apparent viscosity of the binder resin measured by a flow tester is 10%.³The temperature at which Pa · s becomes T₁The apparent viscosity of the resin charge control agent measured by a flow tester is 10⁴The temperature at which Pa · s₂And T₁, T₂Is 0.9 <T₁/ T₂The toner for developing a dry electrostatic image according to any one of claims 1 to 10, which is <1.4, is a main feature.
[0040]
In the twelfth aspect of the present invention, the additive contains 2.1 parts by weight or more of hydrophobically treated silica having a primary particle diameter of 0.01 to 0.03 μm with respect to 100 parts by weight of the base toner. 0.01-0.03μm and specific surface area 60-140m²The toner for developing a dry electrostatic charge image according to any one of claims 1 to 11, comprising 0.4 to 1.0 parts by weight of titanium oxide subjected to hydrophobization treatment / g / g.
[0041]
A thirteenth aspect of the invention is characterized mainly by a dry one-component developer comprising the toner for developing a dry electrostatic image according to the first aspect.
[0042]
According to a fourteenth aspect of the present invention, a dry two-component developer comprising the toner for developing a dry electrostatic image of the first aspect and a carrier is a main feature.
[0043]
In the invention according to claim 15, a latent image forming step of forming a latent image on the latent image holding body, a developing step of developing the latent image using a developer on a developer carrier, and a step of developing the developed toner image 14. An image forming method comprising a transfer step of transferring onto a transfer body and a fixing step of heating and fixing a toner image on the transfer body, wherein the image forming method using the dry single-component developer according to claim 13 as a developer is mainly used. Characteristics.
[0044]
According to a sixteenth aspect of the present invention, a container for holding the one-component developer according to the thirteenth aspect, a container for replenishing the developer, an apparatus having the latent image forming step, an apparatus having the developing step, and the transfer step And an image forming apparatus having a device having the fixing step.
[0045]
In the invention according to claim 17, a latent image forming step of forming a latent image on the latent image holding member, a developing step of developing the latent image using the developer on the developer carrier, and a step of developing the developed toner image 15. An image forming method comprising a transfer step of transferring onto a transfer body and a fixing step of heating and fixing a toner image on the transfer body, wherein the image forming method using the dry two-component developer according to claim 14 as a developer is mainly used. Characteristics.
[0046]
According to an eighteenth aspect of the present invention, a container for holding the dry two-component developer according to the fourteenth aspect, a container for replenishing the toner, an apparatus having the latent image forming step, an apparatus having the developing step, and the transfer step And an image forming apparatus having an apparatus having the fixing step.
[0047]
BEST MODE FOR CARRYING OUT THE INVENTION
In order to solve the above-mentioned problems, the present inventors have focused on the components and composition ratio of the resin charge control agent, and as a result of intensive studies, as a binder resin for full-color toner, a polyester resin suitable for color development and image strength. On the other hand, when a resin charge control agent having a specific component and a specific composition ratio, a specific surface-treated titanium oxide, and silica are used, a high charge amount and a sharp charge amount distribution can be obtained, and the rise of the charge is good. Excellent in soiling, unaffected by changes in greenhouse temperature, and for more than tens of thousands of sheets, contaminates developing carrier (developing roller or sleeve) and developing layer thickness regulating member (blade or roller) and photoconductor filming. It has been found that a toner, a developer and an image forming method for developing an electrostatic image that can be prevented and have good pulverizability and high productivity can be obtained.
[0048]
Hereinafter, the present invention will be described in detail. In the present invention, the binder resin is a polyester, and the charge control agent is at least a sulfonic acid group-containing monomer, an aromatic monomer having an electron withdrawing group, and an acrylate and / or methacrylate monomer and / or an aromatic monomer. This is a dry electrostatic image developing toner containing a resin charge control agent having a vinyl group monomer as a constituent unit, hydrophobic silica, and hydrophobic titanium oxide.
[0049]
As the binder resin used in the toner of the present invention, a polyester resin suitable for the color developing property and image strength is used as a binder resin for a full-color toner. Since several types of toner layers are superposed on a color image, the thickness of the toner layer is increased, resulting in image cracking or defects due to insufficient strength of the toner layer, or loss of appropriate gloss. For this reason, a polyester resin is used to maintain appropriate gloss and excellent strength.
[0050]
The binder resin of the present invention has no THF-insoluble content, and has a weight average molecular weight of 5 × 10 5 in the molecular weight distribution by gel permeation chromatography.²The content of the following components is 4% by weight or less, and the molecular weight is 3 × 10³~ 9 × 10³Is characterized by having one peak in the region. When the THF-insoluble matter enters, the gloss is lowered and the transparency is lowered, so that a high quality image cannot be obtained when an OHP sheet is used. The toner of the present invention has a weight average molecular weight of 5 × 10²By defining the following weight% and defining the ratio of the weight average molecular weight to the number average molecular weight, filming to a blade, a sleeve, or the like is less likely to occur. Also, the weight average molecular weight is 5 × 10²When the content of the following components is 4% by weight or more, the blade or sleeve is contaminated by being used for a long period of time, and filming easily occurs.
[0051]
First, the polyester resin will be described. A polyester resin as a binder resin can be generally obtained by an esterification reaction between a polyhydric alcohol and a polycarboxylic acid. Among the monomers constituting the polyester resin in the present invention, examples of the alcohol monomer including trifunctional or higher polyfunctional monomers include ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, and 1,3-propylene glycol. Diols such as propylene glycol, 1,4-butadieneol, neopentyl glycol, 1,4-butenediol, 1,5-pentanediol, 1,6-hexanediol, bisphenol A, hydrogenated bisphenol A, polyoxypropylene Bisphenol A alkylene oxide adducts such as bisphenol A, other dihydric alcohols, or sorbitol, 1,2,3,6-hexane tetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol , Tripentaerythritol, 1,2,4-butanetriol, 1,2,5-pentanetriol, glycerol, diglycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, tri Examples include methylolethane, trimethylolpropane, 1,3,5-trihydroxybenzene, and other trihydric or higher polyhydric alcohols.
[0052]
Among these monomers constituting the polyester resin, those using a bisphenol A alkylene oxide adduct as a main component monomer are particularly preferably used. When a bisphenol A alkylene oxide adduct is used as a constituent monomer, a polyester having a relatively high glass transition point is obtained due to the nature of the bisphenol A skeleton, and copy blocking resistance and heat storage stability are improved. Further, the presence of the alkyl groups on both sides of the bisphenol A skeleton functions as a soft segment in the polymer, and the color development and the image strength upon fixing the toner are improved. In particular, among the bisphenol A alkylene oxide adducts, those having an ethylene group or a propylene group are preferably used.
[0053]
Among the monomers constituting the polyester resin in the present invention, examples of the acid monomer, including trifunctional or higher valent polyfunctional monomers, include, for example, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, phthalic acid, isophthalic acid Terephthalic acid, cyclohexanedicarboxylic acid, succinic acid, adipic acid, sebacic acid, azelaic acid, malonic acid, or alkenylsuccinic acids or alkylsuccinic acids such as n-dodecenylsuccinic acid, n-dodecylsuccinic acid, and anhydrides of these acids , Alkyl esters, other divalent carboxylic acids, and 1,2,4-benzenetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 1,2,4- Butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, , 3-Dicarboxyl-2-methyl-methylenecarboxypropane, tetra (methylenecarboxyl) methane, 1,2,7,8-octanetetracarboxylic acid, empol trimer acid, and anhydrides, alkyl esters and alkenyls thereof Esters, aryl esters, and other trivalent or higher carboxylic acids can be mentioned.
[0054]
Specific examples of the alkyl ester, alkenyl ester or aryl ester described herein include triethyl 1,2,4-benzenetricarboxylate, trimethyl 1,2,4-benzenetricarboxylate, and triethyl 1,2,4-benzenetricarboxylate. Tri-n-butyl 1,2,4-benzenetricarboxylate, isobutyl 1,2,4-benzenetricarboxylate, tri-n-octyl 1,2,4-benzenetricarboxylate, tri1,2,4-benzenetricarboxylate Examples thereof include 2-ethylhexyl, tribenzyl 1,2,4-benzenetricarboxylate, and tris (4-isopropylbenzyl) 1,2,4-benzenetricarboxylate.
[0055]
The production method for obtaining the polyester used in the toner of the present invention is not particularly limited, and the esterification reaction can be performed by a known method. The transesterification can also be carried out by a known method, and in this case, a known transesterification catalyst can be used. Examples include magnesium acetate, zinc acetate, manganese acetate, calcium acetate, tin acetate, lead acetate, titanium tetrabutoxide and the like. The polycondensation reaction can be performed by a known method, and in this case, a known polymerization catalyst can be used. Specific examples include antimony trioxide and germanium dioxide.
[0056]
The molecular weight distribution of the binder resin used in the toner of the present invention is measured by gel permeation chromatography as follows. The column was stabilized in a heat chamber at 40 ° C., and THF was passed through the column at this temperature as a solvent at a flow rate of 1 ml per minute, and a THF sample solution of a mother toner adjusted to a sample concentration of 0.05 to 0.6% by weight was used. Is injected and measured. Before injecting the THF sample solution, a THF insoluble component is removed with a 0.45 μm liquid chromatography filter.
[0057]
In measuring the molecular weight of the toner sample, the molecular weight distribution of the sample was calculated from the relationship between the logarithmic value of a calibration curve prepared from several types of monodisperse polystyrene standard samples and the count number. As a standard polystyrene sample for preparing a calibration curve, for example, Pressure Chemical Co. Alternatively, a molecular weight of 6 × 10 manufactured by Toyo Soda Kogyo Co., Ltd.², 2.1 × 10³, 4 × 10³, 1.75 × 10⁴, 5.1 × 10⁴, 1.1 × 10⁵3.9 × 10⁵, 8.6 × 10⁵, 2 × 10⁶, 4.48 × 10⁶It is appropriate to use at least about 10 standard polystyrene samples. An RI (refractive index) detector is used as the detector.
[0058]
The presence or absence of THF-insoluble components in the binder resin is determined when preparing a THF sample solution for molecular weight distribution measurement. That is, when a 0.45 μm filter unit is attached to the tip of the syringe and the liquid is pushed out from the syringe, it is determined that there is no THF-insoluble matter unless the filter is clogged.
[0059]
The binder resin used in the present invention preferably has an endothermic peak in DSC in the range of 60 to 70 ° C. If the temperature is lower than 60 ° C., the storage stability of the toner is affected, and a problem such as solidification of the toner in the cartridge or the hopper occurs. On the other hand, when the temperature exceeds 70 ° C., the toner productivity is affected, and problems such as a decrease in feed during pulverization occur. The endothermic peak in DSC is measured by, for example, Rigaku THRMOFLEX TG8110 manufactured by Rigaku Denki Co. under the condition of a heating rate of 10 ° C./min, and the main peak of the endothermic curve is read.
[0060]
Further, the ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) of the binder resin used in the present invention is preferably 2 ≦ Mw / Mn ≦ 10. If Mw / Mn exceeds 10, gloss cannot be obtained when the toner is fixed, and a high-quality image cannot be obtained. When Mw / Mn is less than 2, productivity is reduced in a pulverizing step at the time of toner production, and when used for a long time, blades and sleeves are contaminated, and filming easily occurs.
[0061]
Further, the binder resin used in the present invention preferably has an acid value of 10 KOHmg / g or less in the interaction between a resin charge control agent and an additive described below. It is known that the relationship between the chargeability of a polyester resin and the acid value is substantially proportional to each other, and that the higher the acid value, the greater the negative chargeability of the resin and, at the same time, the environmental characteristics of charging. That is, when the acid value is high, the charge amount increases under low temperature and low humidity, and the charge amount decreases under high temperature and high humidity. The change in the amount of charge due to the environment greatly changes the background stain, the image density, and the color reproducibility, making it difficult to maintain high image quality. In general, when the acid value exceeds 20 KOHmg / g, the charge amount may increase, environmental fluctuation may be deteriorated, and the like.
[0062]
In the polyester resin used in the present invention, the resistance as toner particles is controlled by the chargeability and resistance of the resin charge control agent, hydrophobic silica, and hydrophobic titanium oxide described below. Therefore, if the acid value of the polyester resin exceeds 10 KOHmg / g, the charge control effect of the resin charge control agent, hydrophobic silica, and hydrophobic titanium oxide is impaired. The acid value of the polyester resin used in the present invention is preferably 10 KOH mg / g or less, more preferably 5 KOH mg / g or less.
[0063]
Furthermore, the binder resin used in the present invention has an apparent viscosity of 10 by a flow tester.³The temperature at which Pa · s is reached is preferably from 95 to 120 ° C. If it is lower than 95 ° C., the margin of hot offset at the time of fixing is lost, while if it exceeds 120 ° C., sufficient gloss cannot be obtained. Apparent viscosity is 10³The temperature at which Pa · s is measured is, for example, a CFT-500 model manufactured by Shimadzu Corporation as a flow tester, and a load of 10 kg / cm.²The viscosity was measured at an orifice diameter of 1 mm x a length of 1 mm at a heating rate of 5 ° C / min.³The temperature at which Pa · s is reached is read.
[0064]
Next, the resin charge control agent used in the toner of the present invention will be described.
In general, by adding a sulfonic acid group-containing monomer as a monomer constituting a resin charge control agent, the effect of imparting negative charge to the resin charge control agent is improved. On the other hand, the environmental stability (temperature / humidity stability) of the toner is reduced due to the hygroscopicity. Therefore, it is generally known to use an aromatic monomer having an electron withdrawing group as a copolymer. However, the use of several thousand sheets is sufficient, but if the toner is used for a long period of time of tens of thousands or more, contamination of the developing sleeve and the layer thickness regulating members (blades and rollers) and photoreceptor filming occur, and However, there is a problem that the charging stability and high image quality are not sufficiently maintained, and the productivity is lowered.
[0065]
In order to compensate for such a defect, in the toner of the present invention, (A) a sulfonic acid group-containing monomer and (B) an electron-withdrawing group are used as a binder resin for a full-color toner with respect to a polyester resin which is suitable in terms of color developability and image strength. And (C) three kinds of monomers of an acrylic ester monomer and / or a methacrylic acid ester monomer, or (D) four kinds of (A) to (D) containing an aromatic vinyl monomer further. By using a copolymer containing the above monomer as a resin charge control agent, it is excellent in charge stability and environmental stability over a long period of time, does not contaminate the developing sleeve and layer thickness regulating members (blades and rollers), and has a thin layer. The toner is good in formation, prevents filming of the photoreceptor, maintains high image quality, and provides a toner for developing electrostatic images with high productivity.
[0066]
Further, regarding the molecular weight distribution of the resin charge control agent, the weight average molecular weight was 1 × 10³The following weight percentages are specified. Weight average molecular weight 1 × 10³The following components are low molecular weight components, copolymers, ionomers, residual monomers, and the like, which inhibit the generation of charge and fluctuate the charge under the influence of temperature and humidity. In addition, these components also affect safety such as skin irritation and fish toxicity. Weight average molecular weight 1 × 10³When the following components are 10% by weight or more, the chargeability becomes unstable due to the influence of temperature and humidity.
[0067]
The above effects are presumed to be for the following reasons. That is, the combined use of the sulfonic acid group-containing monomer and the aromatic monomer having an electron-withdrawing group enhances the effect of imparting negative charge. Further, by using an aromatic vinyl monomer in addition to an acrylate monomer and / or a methacrylate ester monomer, the environmental stability of charging is further increased, the resin hardness is increased, the pulverizability is improved, and the development is improved. There is no contamination of the sleeve or the layer thickness regulating member (blade or roller), and the effect of preventing photoconductor filming is improved.
[0068]
In addition, in addition to the low molecular weight components of these resin charge control agents, the resin charge control agent by the combination of these monomers, by combining with a polyester resin suitable from the viewpoint of color development and image strength as a binder resin for full-color toner, An appropriate dispersibility is obtained, a toner for developing an electrostatic image having a sharp charge amount distribution is obtained, and long-term charging stability and high image quality are obtained.
[0069]
Examples of the sulfonate group-containing monomer constituting the resin charge control agent used in the toner of the present invention include an aliphatic sulfonate group-containing monomer and an aromatic sulfonate group-containing monomer. Examples of the aliphatic sulfonic acid group-containing monomer include alkali metal salts such as vinylsulfonic acid, allylvinylsulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, methacryloyloxyethylsulfonic acid, and perfluorooctanesulfonic acid, and alkaline earth metals. Salts, amine salts and quaternary ammonium salts. Examples of the aromatic sulfonic acid group-containing monomer include alkali metal salts such as styrenesulfonic acid, sulfophenylacrylamide, sulfophenylmaleimide, and sulfophenylitaconimide, alkaline earth metal salts, amine salts, and quaternary ammonium salts. . Among the metal salts, salts of heavy metals (nickel, copper, zinc, mercury, chromium, etc.) are not preferable from the viewpoint of safety.
[0070]
Examples of the aromatic monomer having an electron-withdrawing group that constitutes the resin charge control agent used in the toner of the present invention include styrene-substituted products such as chlorostyrene, dichlorostyrene, bromostyrene, fluorostyrene, nitrostyrene, and cyanostyrene; ) Substituted phenyl (meth) acrylate such as acrylate, bromophenyl (meth) acrylate, nitrophenyl (meth) acrylate, chlorophenyloxyethyl (meth) acrylate, chlorophenyl (meth) acrylamide, bromophenyl (meth) acrylamide, nitrophenyl ( Substituted phenyl (meth) acrylamide such as (meth) acrylamide, chlorophenylmaleimide, dichlorophenylmaleimide, nitrophenylmaleimide, nitrochlorophenylmale Phenylmaleimide substituents such as de, chlorophenyl itaconic imides, dichlorophenyl itaconic imides, nitrophenyl itaconic imide, phenyl itaconic imide substituents, such as nitro-chlorophenyl itaconate imide, chlorophenyl vinyl ether, and the like phenyl vinyl ether substituents such as nitro phenyl ether. In particular, substituted phenylmaleimide and substituted phenylitaconimide substituted with a chlorine atom or a nitro group are preferable in terms of charging properties and filming resistance.
[0071]
Further, the acrylate monomer and / or methacrylate monomer constituting the resin charge control agent used in the toner of the present invention include methyl (meth) acrylate, ethyl (meth) acrylate, and propyl (meth) acrylate. , N-butyl (meth) acrylate, isobutyl (meth) acrylate, stearyl (meth) acrylate, dodecyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and the like.
[0072]
Further, examples of the aromatic vinyl monomer constituting the resin charge control agent used in the toner of the present invention include styrene, vinyltoluene, and α-methylstyrene. Regarding the composition ratio of each monomer in the resin charge control agent of the present invention, first, the sulfonic acid group-containing monomer is 1 to 30% by weight, more preferably 2 to 20% by weight, based on the weight of the resin charge control agent. When the amount of the sulfonic acid group-containing monomer is less than 1% by weight, the charge rising performance and the saturated charge amount are not sufficient, and the image tends to be affected. On the other hand, if the content exceeds 30% by weight, the environmental stability of charging deteriorates, the charging amount at high temperature and high humidity is low, and the charging amount at low temperature and low humidity increases, and the charging stability and high image quality of the toner are not sufficiently maintained. Further, there is a problem that contamination of the developing sleeve and the layer thickness regulating members (blades and rollers) and filming of the photoreceptor are apt to occur, and the productivity at the time of producing the toner by the kneading / pulverizing method is reduced.
[0073]
The amount of the aromatic monomer having an electron withdrawing group is 1 to 80% by weight, more preferably 20 to 70% by weight, based on the weight of the resin charge controlling agent. If the amount of the aromatic monomer having an electron-withdrawing group is less than 1% by weight, the charge amount is not sufficient, and background stain and toner scattering are likely to occur. On the other hand, if it exceeds 80% by weight, the dispersion in the toner is poor, the distribution of the charge amount of the toner is widened, the background is liable to be scattered and the toner is scattered, and the maintenance of high image quality is not sufficient.
[0074]
The content of the acrylate monomer and / or the methacrylate monomer is from 10 to 80% by weight, more preferably from 20 to 70% by weight, based on the resin charge control agent. If the content of the acrylate monomer and / or the methacrylate monomer is less than 10% by weight, sufficient environmental stability of charging cannot be obtained, and the pulverizability at the time of toner production by kneading and pulverization methods is not sufficient. The contamination of the developing sleeve and the layer thickness regulating member (blade and roller) and filming of the photoconductor cannot be sufficiently prevented. If it exceeds 80% by weight, the charge rise and the charge amount are not sufficient, and the image is likely to be affected.
[0075]
The amount of the aromatic vinyl monomer is 0 to 30% by weight, more preferably 3 to 20% by weight, based on the weight of the resin charge control agent. When the amount of the aromatic vinyl monomer exceeds 30% by weight, the resin charge control agent becomes hard, the dispersibility in the toner is reduced, the charge distribution is widened, and the background smear and the toner scattering in the machine are liable to occur. Further, the fixability of the toner, particularly the color developability when mixing color toners, becomes poor.
[0076]
In the resin charge control agent used in the toner of the present invention, as described above, a phenylmaleimide-substituted or phenylitaconimide-substituted monomer substituted with a chlorine atom or a nitro group can be used as the aromatic monomer. Variations in volume resistance, which may be caused by residues such as a catalyst, a polymerization inhibitor, and a solvent during the synthesis of these monomers, may occur, which may affect a desired toner charge amount. For this reason, there is a possibility that problems such as rising of the charge of the toner containing the resin negative charge control agent and charge-up of the saturation charge amount may occur.
[0077]
Therefore, in the present invention, a resin charge control agent having a volume resistance in the range of 9.5 to 11.5 Log Ω · cm is used. If the volume resistance of the resin charge control agent is less than 9.5 Log Ω · cm, the toner on the developing roller will not initially obtain a sufficient amount of desired charge, causing background smear and toner scattering. When the volume resistance of the resin charge control agent exceeds 11.5 Log Ω · cm, the toner on the developing roller initially obtains a desired charge amount, but charges up with time, and in the one-component developing method, the toner on the developing roller The thin toner layer is not uniform, and color streaks and unevenness occur on the image. Further, in the two-component developing method, the image density is reduced, and background smear and toner scattering occur. The volume resistance of the resin charge control agent is more preferably 10.0 to 11.0 Log Ω · cm.
[0078]
The measurement of the volume resistance of the resin charge control agent contained in the toner of the present invention complies with JIS K6911. The resin charge control agent is sized with a mesh and conditioned at 23 ° C. and 50% RH. This sample was sampled by an automatic press molding machine with a sample amount of 3 g and a pressure of 500 kg / cm.²To produce a disk-shaped test piece having a thickness of about 2 mm and a diameter of 4 cm. The thickness is measured accurately with a vernier caliper, set in a dielectric loss measuring instrument (TR-10C manufactured by Ando Electric Co., Ltd.), and an AC voltage having a frequency of 1 kHz is applied to measure the volume resistance.
[0079]
The resin charge controlling agent contained in the toner of the present invention has an apparent viscosity of 10 by a flow tester.⁴The temperature at which Pa · s is reached is preferably from 85 to 110 ° C. When the temperature is lower than 85 ° C., an appropriate dispersibility in the toner cannot be obtained, and not only the charge is reduced, but also the storage stability is poor, and the toner is liable to be coagulated and solidified. In addition, in a method obtained from a production step of kneading, pulverizing, and classifying, sticking in the pulverizing step is likely to occur, thereby lowering productivity. On the other hand, when the temperature exceeds 110 ° C., the dispersibility in the toner is reduced, the charge amount distribution is widened, and the toner is liable to be scattered in the background and in the machine. Further, the fixability of the toner, particularly the color developability at the time of color superposition of the color toner, becomes poor. Apparent viscosity is 10⁴The temperature at which Pa · s is measured is, for example, a CFT-500 model manufactured by Shimadzu Corporation as a flow tester, and a load of 10 kg / cm.²The viscosity was measured at an orifice diameter of 1 mm x a length of 1 mm at a heating rate of 5 ° C / min.⁴The temperature at which Pa · s is reached is read.
[0080]
The weight average molecular weight of the resin charge control agent contained in the toner of the present invention is 5 × 10³~ 1 × 10⁵It is preferable that 5 × 10³If it is less than the appropriate dispersibility in the toner is not obtained, and not only the charge is reduced, but also in the method of obtaining the toner from the production process including kneading, pulverization, and classification, sticking in the pulverization process is likely to occur. Decrease productivity. Also 1 × 10⁵If the ratio exceeds the above range, the dispersibility in the toner is reduced, the charge amount distribution is widened, the toner is liable to be scummed or the toner is scattered in the apparatus, and the fixability and the color developing property of the toner are poor. Further, the weight average molecular weight of the resin charge control agent is 1 × 10³It is preferable that the following components are 10% by weight or less. Weight average molecular weight 1 × 10³The following components are low molecular weight components, copolymers, ionomers, residual monomers, and the like, which inhibit the generation of charge and fluctuate the charge under the influence of temperature and humidity. In addition, these components also affect safety such as skin irritation and fish toxicity. Weight average molecular weight 1 × 10³The following components are more preferably at most 6% by weight.
[0081]
The apparent viscosity of the binder resin of the present invention measured by a flow tester is 10%.³The temperature at which Pa · s becomes T₁The apparent viscosity of the resin charge control agent measured by a flow tester is 10⁴The temperature at which Pa · s becomes T₂And T₁, T₂Is 0.9 <T₁/ T₂It is preferable to satisfy the relationship of <1.4.
[0082]
The dispersion of the charge control agent in the binder resin is a major factor that determines the charging performance of the toner. In the present invention, by combining a specific binder resin and a specific resin charge control agent, a toner having good chargeability and excellent charge rising property can be obtained. However, it is apparent that the dispersibility (compatibility) between the binder resin and the resin charge control agent affects the charging performance as described above. The present inventors focused on the apparent viscosities of the binder resin and the resin charge control agent by individual flow testers, studied the degree of dispersion thereof, and obtained an optimum range. T₁/ T₂When the ratio is less than 0.9, the apparent viscosities of the binder resin and the resin charge control agent are close to each other, and the binder resin and the resin charge control agent become compatible with each other. T₁/ T₂If the ratio exceeds 1.4, the apparent viscosities of the binder resin and the resin charge control agent are too far apart, the resin charge control agent becomes poorly dispersed, and the initial background fouling and the decrease in charge over time occur. By specifying the constituent monomers, specifying the apparent viscosity, and specifying the apparent viscosity ratio of the specific resin charge control agent to the binder resin to be dispersed, the resin exhibits good chargeability and hardly causes filming.
[0083]
The amount of the resin charge control agent used in the toner of the present invention is preferably from 0.1 to 20% by weight, and more preferably from 0.5 to 10% by weight, based on the toner particles. If the amount is less than 0.1% by weight, the rise of the charge and the amount of charge are not sufficient, and the image tends to be affected such as background stains and dust. If the content is more than 20% by weight, the dispersion becomes poor, the charge amount distribution becomes wide, and the background soiling and toner scattering in the machine are liable to occur.
[0084]
Examples of the additives used in the toner of the present invention include hydrophobically treated silica having a primary particle diameter of 0.01 to 0.03 μm, and a specific surface area of 60 to 140 m having a primary particle diameter of 0.01 to 0.03 μm.²/ G of hydrophobized titanium oxide having a specific performance. By using these additives as the polyester resin and the resin charge control agent, a toner having stable chargeability can be obtained.
[0085]
That is, by attaching hydrophobically treated silica having a primary particle diameter of 0.01 to 0.03 μm to the surface of the base toner, necessary fluidity and chargeability are imparted to the toner, and the toner is exposed on the developing roller and from the developing roller. Good developability on the body. The addition amount of this type of silica is preferably 2.1 parts by weight or more based on 100 parts by weight of the base toner, whereby the thin layer of the toner on the developing roller becomes uniform, and the unevenness of the thin layer is largely improved. In addition, the long-term stirring of the developing roller prevents the generation of white streaks due to the fusion of the toner to the stirring developer applying blade. If the amount is smaller than the above range, sufficient fluidity of the toner may not be obtained, and a necessary amount of toner may not be supplied to the developing roller, or a required charge amount of the toner may not be obtained. Further, the thin layer of the toner on the developing roller becomes non-uniform, so that uniform development of the toner and an image cannot be obtained, or white streaks may occur due to the fusion of the toner to the stirring developer coating blade.
[0086]
The primary particle size is 0.01 to 0.03 μm and the specific surface area is 60 to 140 m.²By adhering the hydrophobicized titanium oxide of / g to the surface of the base toner, the chargeability of the toner is stabilized, and in particular, the charge rising property and the charge-up are prevented. The addition amount of this type of titanium oxide is preferably 0.4 to 1.0 part by weight based on 100 parts by weight of the base toner. If the amount is less than 0.4 parts by weight, the chargeability of the toner may be too high to sufficiently develop the toner. When added in an amount of more than 1.0 part by weight, the chargeability of the toner may be too low, causing the toner to scatter from the developing roller or to cause soiling of the background. The mother toner refers to particles in the course of production containing materials other than additives, at least a binder resin, a colorant, and a resin charge control agent.
[0087]
Among the additives used in the present invention, the hydrophobic titanium oxide is obtained by subjecting titanium oxide fine particles having a water-soluble component content of 0.2% by weight or more produced by a wet method to a surface treatment, and the additive is made of UV. In the absorption method, the transmittance at 300 nm is 35% or more, and the transmittance at 600 nm is 80% or more.
[0088]
Titanium oxide is generally produced by a wet method. In general, as the ore containing titanium, auburnite, anatase, brookite, ilmenite and the like are used. There is a sulfuric acid method in which concentrated sulfuric acid is added to and dissolved in these ores, or a chlorine method in which these ores are red hot-dehydrated with a carbon substance and exposed to chlorine gas. Both are titanium hydroxide Ti (OH)₂Is purified and TiO is hydrolyzed in the final step.₂Crystals are precipitated. Therefore, water-soluble components are present to some extent. These are alkali metal ions and acid components contained in ores, catalysts and treating agents used in the production process.₄ ^2-, SO₄ ^2-, Cl⁻, Na⁺, Mg²⁺, Li⁺And so on. It has been known that these water-soluble components affect the chargeability and the resistance, and it is said that controlling the amount to less than 0.2% by weight maintains a high charge amount.
[0089]
However, in the present invention, the titanium oxide was found not to have a higher chargeability but to have a function in the resistance and the particle size distribution, leading to the present invention. That is, by using titanium oxide having a water-soluble component amount of 0.2% by weight or more, an increase in the charge amount with the lapse of time is suppressed, and the effect can be obtained when used in combination with silica. The amount of the water-soluble component is determined according to JIS K5116-1973.
[0090]
It is common to apply a surface treatment with a coupling agent or the like in order to enhance the function of the titanium oxide, but the amount of water-soluble components of the titanium oxide affects the surface treatment, and the obtained surface-treated titanium oxide has It also affects resistance and charging characteristics. Furthermore, the degree of dispersion in the surface treatment changes the secondary cohesion of titanium oxide. In general, uniform treatment or high dispersion treatment may be performed to maintain the primary particle diameter. However, titanium oxide alone often causes problems such as an increase in charging over time and adhesion to a photoreceptor. Therefore, in the present invention, although the degree of dispersion is increased, the problem is solved by setting the resistance low. An index representing the particle size of titanium oxide is based on the transmittance in a specific solvent.
[0091]
In the present invention, the transmittance at 300 nm in the UV absorption method is preferably 35% or more, and the transmittance at 600 nm is preferably 80% or more. Titanium oxide surface-treated with a large amount of water-soluble components in order to set low resistance requires a transmittance of 300 nm of 35% or more. Since the resistance is low, the particle size is controlled to be small, so that the toner is easily dispersed on the toner surface. On the other hand, the transmittance at 600 nm needs to be 80% or more. If it is less than 80%, the surface treatment with a coupling agent or the like is not uniform, and an aggregate is formed by the treatment.
[0092]
The measurement of the transmittance was performed as follows. 20 g of a reagent (polyoxyethylene octyl phenyl ether) was precisely weighed, placed in a beaker, and added with ion-exchanged water so that the solid content concentration became 1 wt%. This aqueous solution was dispersed by being applied to an ultrasonic vibrator (HONDA W-113), and further stirred with a magnetic stirrer to prepare a measurement solvent. Next, 25 mg of a sample (titanium oxide) was placed in a 300 ml Erlenmeyer flask, 250 g of a measuring solvent was added thereto, and the mixture was stirred and dispersed with a magnetic stirrer for 5 minutes. Thereafter, the Erlenmeyer flask was placed on an ultrasonic vibrator and dispersed for 5 minutes. Occasionally, the flask was shaken by hand to encourage dispersion of the aggregates. Immediately after the dispersion, 2 g of the dispersion was measured and placed in a 30 ml sample bottle, and 18 g of ion-exchanged water was added thereto. Gently shake the mixture by hand gently so as not to make it bubbling, take the obtained mixed solvent in a glass cell with a path width of 1 cm, and set it in a UV device (Shimadzu UV-3100 spectrophotometer), in the range of 300 to 700 nm. The absorbance was measured with.
[0093]
As the coloring material used in the toner of the present invention, all known dyes and pigments can be used. For example, carbon black, nigrosine dye, iron black, naphthol yellow S, Hansa yellow (10G, 5G, G), cadmium yellow, yellow Iron oxide, loess, graphite, titanium yellow, polyazo yellow, oil yellow, Hansa yellow (GR, A, RN, R), Pigment yellow L, benzidine yellow (G, GR), permanent yellow (NCG), Vulcan fast Yellow (5G, R), Tartrazine lake, Quinoline yellow lake, Anthrazan yellow BGL, Isoindolinone yellow, Bengala, Lead red, Lead red, Cadmium red, Cadmium mercury red, Antimony red, Permanent red 4R, Para red, Phi Sailor, para Roll Ortho Nitroaniline Red, Risor Fast Scarlet G, Brilliant Fast Scarlet, Brilliant Carmine Min BS, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belkan Faster Rubin B, Brilliant Scarlet G, Lisor Rubin GX , Permanent Red F5R, Brilliant Carmine 6B, Pigment Scarlett 3B, Bordeaux 5B, Toluidine Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bon Maroon Light, Bon Maroon Medium, Eosin Lake, Rhodamine Lake B, Rhodamine Lake Y, Alizarin Lake, Thioindigo Red B, Thioindigo Maroon, Oil Red, Quinacridone Red, Pi Zolone Red, Polyazo Red, Chrome Permillion, Benzidine Orange, Perinone Orange, Oil Orange, Cobalt Blue, Cerulean Blue, Alkaline Blue Lake, Peacock Blue Lake, Victoria Blue Lake, Metal-Free Phthalocyanine Blue, Phthalocyanine Blue, Fast Sky Blue, Indance Renblue (RS, BC), indigo, ultramarine, navy blue, anthraquinone blue, fast violet B, methyl violet lake, cobalt violet, manganese violet, dioxane violet, anthraquinone violet, chrome green, zinc green, chromium oxide, pyridian, emerald green , Pigment Green B, Naphthol Green B, Green Gold, Acid Green Lake, Malachite Green Lake, phthalocyanine green, anthraquinone green, titanium oxide, zinc white, lithobon and mixtures thereof can be used. The amount used is generally 0.1 to 50 parts by weight based on 100 parts by weight of the binder resin.
[0094]
As the charge control agent used in the present invention, a conventionally known charge control agent may be used in combination. For example, a simple substance or compound of a nigrosine dye, a triphenylmethane dye, a chromium-containing metal complex dye, a molybdate chelate pigment, a rhodamine dye, an alkoxy amine, a quaternary ammonium salt, a fluorine-modified quaternary ammonium salt, an alkylamide, and phosphorus , Tungsten alone or a compound, a metal salt compound of a salicylic acid derivative, or the like.
[0095]
The toner of the present invention includes, as other additives, for example, Teflon (R), fluoropolymer, low molecular weight polyolefin, metal oxide (such as aluminum oxide, tin oxide, and antimony oxide), and conductivity imparting agent (such as carbon black and tin oxide). , A magnetic material, and those obtained by surface-treating these additives may be used in combination. These additives may be used alone or in combination of two or more, and the content is generally 0.1 to 10 parts by weight based on 100 parts by weight of the toner.
[0096]
The toner of the present invention may be a magnetic toner containing a magnetic material. Magnetic materials include iron oxide (magnetite, ferrite, hematite, etc.), metal (iron, cobalt, nickel, etc.), aluminum and cobalt, copper, lead, magnesium, tin, zinc, antimony, beryllium, bismuth, calcium, An alloy or a mixture of cadmium, manganese, selenium, titanium, tungsten, vanadium, and the like can be given. These magnetic materials preferably have a volume average particle size of about 0.1 to 2 μm, and the amount contained in the toner is 5 to 150 parts by weight based on 100 parts by weight of the binder resin.
[0097]
The toner of the present invention may be used as a two-component developer using a carrier. The carrier used here may be any conventional system such as iron powder, ferrite, magnetite, and glass beads. The carrier may be coated with a resin. In this case, the resin used is a known one such as polyfluorocarbon, polyvinyl chloride, polyvinylidene chloride, phenol resin, polyvinyl acetal, acrylic resin, and silicone resin. I have. If necessary, a conductive powder or the like may be contained in the coating resin. As the conductive powder, metal powder, carbon black, titanium oxide, tin oxide, zinc oxide and the like can be used. These conductive powders preferably have an average particle size of 1 μm or less. When the average particle diameter is larger than 1 μm, it becomes difficult to control the electric resistance. The mixing ratio of the toner and the carrier in the two-component developer is generally 0.5 to 20.0 parts by weight of the toner with respect to 100 parts by weight of the carrier.
[0098]
The method for producing the toner of the present invention may be any conventionally known method, at least a step of mechanically mixing the toner components of the binder resin, the charge controlling agent and the colorant, a step of melt-kneading, and a step of pulverizing, And a classifying step. In addition, in the step of mechanically mixing and the step of melt-kneading, there is also included a production method of returning and reusing powders other than particles which are products obtained in a step of pulverization or classification.
[0099]
The powder (by-product) other than the particles that become the product referred to here means fine particles or coarse particles other than the components that become the product having the desired particle size obtained in the pulverizing step after the step of melt-kneading, and the classification that is subsequently performed It means fine particles and coarse particles other than the components which are generated in the process and have a desired particle size. In the mixing step or the melt-kneading step of such a by-product, it is preferable to mix the raw material and preferably 1 to 20 parts by weight of the by-product with respect to the main raw material 100.
[0100]
The mixing step of mechanically mixing the toner component of at least the binder resin, the colorant, and the resin charge control agent, and the mixing step of mechanically mixing the toner component containing the by-product with the binder resin, the colorant, and the resin charge control agent include: It may be performed under normal conditions using a normal mixer or the like with a rotating blade, and there is no particular limitation.
[0101]
After the completion of the above mixing step, the mixture is then charged into a kneader and melt-kneaded. As the melt kneader, a uniaxial or biaxial continuous kneader or a batch kneader using a roll mill can be used. For example, a KTK twin screw extruder manufactured by Kobe Steel, a TEM extruder manufactured by Toshiba Machine Co., a twin screw extruder manufactured by Kay Kay, a PCM twin screw extruder manufactured by Ikegai Iron Works, Bus A co-kneader or the like is preferably used. It is important that the melt-kneading is performed under appropriate conditions so as not to cause the molecular chains of the binder resin to be cut. Specifically, the melt-kneading temperature should be determined with reference to the softening point of the binder resin. If the temperature is lower than the softening point, cutting is severe, and if the temperature is too high, dispersion does not proceed.
[0102]
After the completion of the above-described melt-kneading process, the kneaded material is then pulverized. In this pulverization step, it is preferable to first perform coarse pulverization and then finely pulverize. At this time, a method of crushing by colliding with a collision plate in a jet stream, crushing by colliding particles in a jet stream, or crushing by a narrow gap between a mechanically rotating rotor and a stator is preferably used. After the completion of the pulverizing step, the pulverized product is classified in an air stream by centrifugal force or the like, thereby producing a developer having a predetermined particle size, for example, an average particle size of 5 to 20 μm.
[0103]
In order to produce the toner of the present invention, the hydrophobic silica fine powder mentioned above in the base toner produced as described above in order to enhance the fluidity and the preservability, the developability and the transferability as a developer. Inorganic fine particles such as are added and mixed. A general powder mixer is used for mixing the external additives, but it is preferable that the internal temperature can be adjusted by equipping a jacket or the like. In order to change the history of the load applied to the external additive, the external additive may be added during or gradually. Of course, the rotation speed, rolling speed, time, temperature, etc. of the mixer may be changed. A strong load may be applied first, followed by a relatively weak load, or vice versa. Examples of the mixing equipment that can be used include a V-type mixer, a rocking mixer, a Lodige mixer, a Nauter mixer, and a Henschel mixer.
[0104]
【Example】
Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples, but the present invention is not limited to only these Examples. In the following examples, parts and percentages are by weight unless otherwise specified.
[0105]
(Example of resin synthesis)
Synthesis Example 1
740 g of polyoxypropylene (2,2) -2,2-bis (4-hydroxyphenyl) propane was placed in a four-neck separable flask equipped with a stirrer, thermometer, nitrogen inlet, falling condenser, and condenser. Esterification catalyst of 300 g of ethylene (2,2) -2,2-bis (4-hydroxyphenyl) propane, 466 g of dimethyl terephthalate, 80 g of isododecenyl succinic anhydride, and 114 g of tri-n-butyl 1,2,4-benzenetricarboxylate Added with. Under a nitrogen atmosphere, the pressure was raised to normal temperature to 210 ° C. in the first half, and the reaction was carried out with stirring at 210 ° C. in the latter half under reduced pressure. This gives a molecular weight of 5 × 10²The following content: 3.5%, molecular weight main peak: 7.5 × 10³, Tg 62 ° C, Mw / Mn ratio 5.1, acid value 2.3 KOHmg / g, apparent viscosity 10 by flow tester.³A polyester resin having a Pa · s temperature of 112 ° C. (hereinafter, polyester resin A) was obtained. The obtained polyester resin did not contain THF-insoluble components.
[0106]
Synthesis Example 2
725 g of polyoxypropylene (2,2) -2,2-bis (4-hydroxyphenyl) propane, 165 g of polyoxyethylene (2,2) -2,2-bis (4-hydroxyphenyl) propane, 500 g of terephthalic acid, 130 g of isododecenyl succinic anhydride and 170 g of triisopropyl 1,2,4-benzenetricarboxylate were added to the flask together with the esterification catalyst. These were reacted with the same apparatus and the same recipe as in Synthesis Example 1 to give a molecular weight of 5 × 10²The following content 3.0%, molecular weight main peak 8 × 10³, Tg 62 ° C, Mw / Mn ratio 4.7, acid value 0.5 KOHmg / g, apparent viscosity 10 by flow tester³A polyester resin having a Pa · s temperature of 116 ° C. (hereinafter, polyester resin B) was obtained.
[0107]
Synthesis Example 3
650 g of polyoxypropylene (2,2) -2,2-bis (4-hydroxyphenyl) propane, 650 g of polyoxyethylene (2,2) -2,2-bis (4-hydroxyphenyl) propane, 515 g of isophthalic acid, 70 g of isooctenyl succinic acid and 80 g of 1,2,4-benzenetricarboxylic acid were added to the flask together with the esterification catalyst. These were reacted with the same apparatus and the same recipe as in Synthesis Example 1 to give a molecular weight of 5 × 10²The following content 2.1%, molecular weight main peak 8.2 × 10³, Tg 61 ° C, Mw / Mn ratio 4.6, acid value 10.0 KOHmg / g, apparent viscosity 10 by flow tester³A polyester resin having a Pa · s temperature of 117 ° C. (hereinafter, polyester resin C) was obtained.
[0108]
(Example of synthesis of resin charge control agent)
Synthesis Example 1
350 parts of 3,4-dichlorophenylmaleimide and 100 parts of 2-acrylamido-2-methylpropanesulfonic acid were copolymerized in dimethylformaldehyde (DMF) under boiling point for 8 hours using di-t-butyl peroxide as an initiator. Subsequently, 500 parts of n-butyl acrylate and 50 parts of styrene were added, and graft polymerization was performed for 4 hours using di-t-butyl peroxide as an initiator. Then, DMF was removed by drying under reduced pressure to obtain a volume resistance of 10.5 Log Ω · cm. , Weight average molecular weight 1 × 10⁴, Apparent viscosity is 10⁴Temperature at which Pa · s is 96 ° C., weight average molecular weight 1 × 10³The following resin charge control agent 1 having a content of 6% was obtained.
[0109]
Synthesis Example 2
600 parts of m-nitrophenylmaleimide and 100 parts of perfluorooctanesulfonic acid were copolymerized in DMF at a boiling point using di-t-butyl peroxide as an initiator for 8 hours. Next, 250 parts of 2-ethylhexyl acrylate and 30 parts of styrene were added, and graft polymerization was performed for 4 hours using di-t-butyl peroxide as an initiator. Then, DMF was removed by drying under reduced pressure, and the volume resistance was 9.5 Log Ω · cm. , Weight average molecular weight 5.5 × 10³, Apparent viscosity is 10⁴Temperature at which Pa · s is 85 ° C., weight average molecular weight 1 × 10³A resin charge control agent 2 having the following content of 8% was obtained.
[0110]
Synthesis Example 3
500 parts of 3,4-dichlorophenylmaleimide and 150 parts of 2-acrylamido-2-methylpropanesulfonic acid were copolymerized in DMF at a boiling point of 8 hours using di-t-butyl peroxide as an initiator. Then, 350 parts of n-butyl acrylate and 250 parts of α-methylstyrene were added, and graft polymerization was carried out for 4 hours using di-t-butyl peroxide as an initiator. 0.5 Log Ω · cm, weight average molecular weight 9.6 × 10⁴, Apparent viscosity is 10⁴Temperature at which Pa · s is 110 ° C., weight average molecular weight 1 × 10³A resin charge control agent 3 having the following content of 5% was obtained.
[0111]
Synthesis Example 4
400 parts of 3,4-dichlorophenylmaleimide and 200 parts of perfluorooctanesulfonic acid were copolymerized in DMF at a boiling point of 8 hours using di-t-butyl peroxide as an initiator. Next, 300 parts of n-butyl acrylate was added, and graft polymerization was carried out for 4 hours using di-t-butyl peroxide as an initiator. Then, DMF was removed by drying under reduced pressure to obtain a volume resistance of 10.4 Log Ω · cm and a weight average molecular weight. 1.5 × 10⁴, Apparent viscosity 10⁴Temperature at which Pa · s is 105 ° C., weight average molecular weight 1 × 10³The following resin charge control agent 4 having a content of 6% was obtained.
[0112]
Synthesis Example 5
400 parts of 3,4-dichlorophenylmaleimide and 100 parts of 2-acrylamido-2-methylpropanesulfonic acid were copolymerized in DMF at a boiling point of 8 hours using di-t-butyl peroxide as an initiator. Next, 500 parts of n-butyl acrylate and 100 parts of styrene were added and dissolved. After graft polymerization for 4 hours using di-t-butyl peroxide as an initiator, DMF was removed by drying under reduced pressure to obtain a volume resistance of 9.3 LogΩ.・ Cm, weight average molecular weight 3 × 10⁴, Apparent viscosity is 10⁴Temperature at which Pa · s is 101 ° C., weight average molecular weight 1 × 10³The following resin charge control agent 5 having a content of 6% was obtained.
[0113]
(Example of additive)
The silica shown in (1) and (2) below was used as an additive.
(I) Hydrophobized silica having a primary particle diameter of 0.01 to 0.03 μm shown in Table 1
[0114]
[Table 1]

[0115]
(II) Primary particle size 0.01 to 0.03 μm and specific surface area 60 to 140 m²/ G of hydrophobized titanium oxide
[0116]
Synthesis Example 1
300 g of titanium oxide (MT-150A manufactured by Teica) containing 0.35% of a water-soluble component prepared by a wet method and having a primary average particle size of 0.015 μm is dissolved in a toluene solution in which 35 g of isobutylmethoxysilane is dissolved. It was added and dispersed by stirring. Thereafter, the solvent was dried up and pulverized by a jet mill to obtain a titanium oxide (titanium oxide II-1) treated with a coupling agent.
[0117]
Synthesis Example 2
300 g of titanium oxide (MT-150A manufactured by Teica) containing 0.35% of a water-soluble component produced by a wet method and having a primary average particle size of 0.015 μm is added to a toluene solution in which 25 g of isobutylmethoxysilane is dissolved. It was added and dispersed by stirring. Thereafter, the solvent was dried up and pulverized by a jet mill to obtain a coupling agent-treated titanium oxide (titanium oxide II-2).
[0118]
Synthesis Example 3
A toluene solution in which 300 g of titanium oxide (MT-150A manufactured by Teica) containing 0.35% of a water-soluble component produced by a wet method and having a primary average particle size of 0.015 μm and 30 g of methyltrimethoxysilane is dissolved. And dispersed. Thereafter, the solvent was dried up and pulverized by a jet mill to obtain a coupling agent-treated titanium oxide (titanium oxide II-3).
[0119]
Synthesis Example 4
300 g of titanium oxide (MT-150A manufactured by Teica) containing 0.35% of a water-soluble component produced by a wet method and having a primary average particle size of 0.015 μm was dissolved in 30 g of n-butyltrimethoxysilane. It was added to the toluene solution and dispersed. Thereafter, the solvent was dried up and pulverized by a jet mill to obtain a coupling agent-treated titanium oxide (titanium oxide II-3).
[0120]
Table 2 shows the characteristic values of the obtained titanium oxide.
[0121]
[Table 2]

[0122]
Example 1
The coloring material was treated according to the following recipe.
Yellow colorant formulation:
100 parts by weight of polyester resin A
C. I. Pigment Yellow 180 100 parts by weight
Red colorant formulation:
100 parts by weight of polyester resin A
C. I. Pigment Red 122 100 parts by weight
Blue colorant formulation:
100 parts by weight of polyester resin A
C. I. Pigment Blue 15.3 100 parts by weight
Black colorant formula:
100 parts by weight of polyester resin A
100 parts by weight of carbon black
[0123]
After mixing the above-mentioned materials for each color in a Henschel mixer, the mixture was put into an air-cooled two-roll mill, and melt-kneaded for 15 minutes after being put. Thereafter, the kneaded product was rolled and cooled, and roughly ground with a hammer mill to obtain a polyester resin-treated coloring material.
Next, a toner was prepared according to the following formulation.
Yellow toner formulation;
91 parts by weight of polyester resin A
12 parts by weight of yellow colorant treated with polyester resin A
3 parts by weight of resin charge control agent 1
Magenta toner formula:
92 parts by weight of polyester resin A
10 parts by weight of red colorant treated with polyester resin A
3 parts by weight of resin charge control agent 1
Cyan toner formula:
94 parts by weight of polyester resin A
6 parts by weight of blue colorant treated with polyester resin A
3 parts by weight of resin charge control agent 1
Black toner formula:
90 parts by weight of polyester resin A
12 parts by weight of black colorant treated with polyester resin A
2 parts by weight of blue colorant treated with polyester resin A
3 parts by weight of resin charge control agent 1
[0124]
The above-mentioned materials were put into a Henschel mixer for each color and mixed, and the obtained mixture was put into a roll mill heated to 110 ° C., and was melt-kneaded for 30 minutes after putting. Thereafter, the kneaded material was cooled, roughly pulverized by a hammer mill, and finely pulverized by an air jet mill. Further, fine powder was removed by an air classifier to obtain toner of each color. The polyester resin A and T of the resin charge control agent 1₁/ T₂Was 1.16.
[0125]
The following additives were mixed with a Henschel mixer to 100 parts by weight of each color toner thus obtained to obtain a one-component developer.
I-2 hydrophobic silica 2.5 parts by weight
II-1 hydrophobic titanium oxide 0.8 parts by weight
The obtained one-component developer was set on a commercially available digital full-color printer (IPSiO Color 6500, manufactured by Ricoh Company) to form an image. The obtained image was clear and no abnormality such as background stain was observed. When the developing roller was visually observed, the thin toner layer on the roller was uniform. When the charge amount on the developing roller was measured by a suction method, the yellow developer was −35 μC / g, the magenta developer was −30 μC / g, the cyan developer was −31 μC / g, and the black developer was −32 μC / g. there were. An image was similarly formed under a high temperature and high humidity condition of 27 ° C. and 80% RH and a low temperature and low humidity condition of 10 ° C. and 15% RH, but no change was observed and a good image was formed. When a durability test was performed for a total of 40,000 sheets of full-color images in each environment continuously at normal temperature, low temperature, low humidity, high temperature, high humidity, and normal temperature, no remarkable change was observed in the fixed image. The image was clear with no background contamination. When the developing roller was visually observed, no remarkable change was observed in the toner thin layer on the roller. At this time, the charge amount of the developer was 31 μC / g for a yellow developer, 29 μC / g for a magenta developer, -29 μC / g and black developer -27 μC / g. Visual observation of the developing roller, blade, and photoreceptor showed no filming.
[0126]
Example 2
The coloring material was treated according to the following recipe.
Yellow colorant formulation:
100 parts by weight of polyester resin C
C. I. Pigment Yellow 180 100 parts by weight
Red colorant formulation:
100 parts by weight of polyester resin C
C. I. Pigment Red 146 100 parts by weight
Blue colorant formulation:
100 parts by weight of polyester resin C
C. I. Pigment Blue 15.3 100 parts by weight
Black colorant formula:
100 parts by weight of polyester resin C
100 parts by weight of carbon black
[0127]
After mixing the above-mentioned materials for each color in a Henschel mixer, the mixture was put into an air-cooled two-roll mill, and melt-kneaded for 15 minutes after being put. Thereafter, the kneaded product was rolled and cooled, and roughly ground with a hammer mill to obtain a polyester resin-treated coloring material.
Next, a toner was prepared according to the following formulation.
Yellow toner formulation;
91 parts by weight of polyester resin C
12 parts by weight of yellow colorant treated with polyester resin C
Resin charge control agent 4 3 parts by weight
Magenta toner formula:
92 parts by weight of polyester resin C
10 parts by weight of red colorant treated with polyester resin C
Resin charge control agent 4 3 parts by weight
Cyan toner formula:
94 parts by weight of polyester resin C
6 parts by weight of blue colorant treated with polyester resin C
Resin charge control agent 4 3 parts by weight
Black toner formula:
90 parts by weight of polyester resin C
12 parts by weight of black colorant treated with polyester resin C resin
2 parts by weight of blue colorant treated with polyester resin C resin
Resin charge control agent 4 3 parts by weight
[0128]
The above-mentioned materials were put into a Henschel mixer for each color and mixed, and the obtained mixture was put into a twin-screw continuous kneader heated to 80 ° C. and melt-kneaded. Thereafter, the kneaded material was cooled, coarsely pulverized by a hammer mill, and finely pulverized by an airflow type pulverizer. Further, fine powder was removed by an air classifier to obtain toner of each color. The polyester resin C and the T of the resin charge control agent 4₁/ T₂Was 1.11. The following additives were mixed with 100 parts by weight of the obtained toners of each color by a Henschel mixer.
I-3 hydrophobic silica 2.1 parts by weight
II-4 hydrophobic titanium oxide 1.0 part by weight
6 parts by weight of the obtained toner and 94 parts of a silicone resin-coated carrier were mixed to prepare a two-component developer. The obtained two-component developer was set in a commercially available digital full-color printer (IPSiO Color 7100 manufactured by Ricoh) to form an image. The obtained image was clear without background contamination. No abnormalities were observed in the image and the charge at high temperature and high humidity, and at low temperature and low humidity. Even when a durability test was performed on a full-color image of up to 10,000 sheets, no abnormal image was observed. After the test, the inside of the machine was observed, but no scattering or the like was observed, and there was no adhesion to the photoreceptor.
[0129]
Comparative Example 1
(Titanium oxide treatment)
Titanium oxide (MT-150A, manufactured by Teica) containing 0.35% of a water-soluble component prepared by a wet method was washed with water to obtain titanium oxide having a water-soluble component of 0.15%. 300 g of this titanium oxide was added to and dispersed in a toluene solution in which 35 g of isobutyltrimethoxysilane was dissolved. Thereafter, the solvent was dried up, finely pulverized by a jet mill, and further highly dispersed by a pin mill to obtain a coupling agent treated titanium oxide (hydrophobic titanium oxide II-5). When the absorbance of the obtained surface-treated titanium oxide was measured, the transmittance at 300 nm was 21%, and the transmittance at 600 nm was 97%.
[0130]
Next, the following additives were mixed with 100 parts by weight of each color toner obtained in Example 1 to obtain a one-component developer.
I-2 hydrophobic silica 2.4 parts by weight
II-5 hydrophobic titanium oxide 0.6 parts by weight
The obtained one-component developer was set on a commercially available digital full-color printer (IPSiO Color 6500 manufactured by Ricoh Company) to form an image. The obtained image was clear and no abnormality such as background stain was observed. When the developing roller was visually observed, the thin toner layer on the roller was uniform. When the charge amount on the developing roller was measured by a suction method, the yellow developer was −43 μC / g, the magenta developer was −36 μC / g, the cyan developer was −38 μC / g, and the black developer was −35 μC / g. there were. When an image was formed under a high temperature and high humidity condition of 27 ° C. and 80% RH, the image was blurred. When an image was similarly formed under a low-temperature and low-humidity condition of 10 ° C. and 15% RH, a faint image with a low ID was obtained. When a durability test using full-color images was performed in each environment continuously at normal temperature, low temperature and low humidity, high temperature and high humidity, and normal temperature, abnormalities such as background dirt, dust, and stripes on the images occurred. At this point, when the developing roller was visually observed, streaks occurred in the circumferential direction in the thin toner layer on the roller. When the charge amount of the developer was measured, it was found that the yellow developer had deteriorated to 28 μC / g, the magenta developer to 22 μC / g, the cyan developer to 25 μC / g, and the black developer to 21 μC / g.
[0131]
【The invention's effect】
As described above, according to claim 1, in a toner for developing a dry electrostatic image mainly containing at least a binder resin, a coloring material, a charge control agent, and an additive, the binder resin is one or more kinds of polyester resins. The polyester resin does not contain a THF-insoluble component, and has a molecular weight of 5 × 10 5 in a molecular weight distribution by gel permeation chromatography.²The content of the following components is 4% by weight or less, and the weight molecular weight is 3 × 10³~ 9 × 10³Wherein the charge control agent comprises a resin charge control agent, and the resin charge control agent has at least (A) a sulfonate group-containing monomer and (B) an electron withdrawing group as monomers. Among the aromatic monomer, (C) an acrylate monomer and / or a methacrylate monomer, and (D) an aromatic vinyl monomer, (A) to (C) or (A) to (D) are constituent units; The volume resistance of the resin charge control agent is 9.5 to 11.5 Log Ω · cm, and the weight average molecular weight of the resin charge control agent is 1 × 10³The content of the following components is 10% by weight or less, and the additive has a hydrophobic particle-treated silica having a primary particle diameter of 0.01 to 0.03 μm and a primary particle diameter of 0.01 to 0.03 μm. Specific surface area 60-140m²/ G of titanium oxide subjected to hydrophobizing treatment, wherein the titanium oxide is obtained by subjecting titanium oxide fine particles having a water-soluble component content of 0.2% by weight or more produced by a wet method to a surface treatment. The dry electrostatic image developing toner having a transmittance at 300 nm of 35% or more and a transmittance at 600 nm of 80% or more prevents a decrease in gloss due to dispersion and precipitation of a THF-insoluble component, By defining the ratio of the weight average molecular weight to the number average molecular weight, filming on blades and sleeves is prevented, and by regulating the molecular weight distribution in gel permeation chromatography, By suppressing the occurrence of contamination and filming, and by regulating the volume resistance of the resin charge control agent, images can be printed without background contamination and toner scattering. , A stable image free of unevenness is obtained, and by regulating the weight average molecule of the resin charge control agent, the dispersion of the control agent in the toner is improved, and the production process defects can be eliminated. By using specific silica and titanium oxide as additives together with the polyester and the charge control agent, a toner having stable chargeability can be obtained.
[0132]
According to claim 2, the endothermic peak in DSC of the binder resin is in the range of 60 to 70 ° C, and the toner for developing a dry electrostatic image according to claim 1, wherein storage stability and toner productivity are obtained. Can be obtained.
[0133]
According to Claim 3, the ratio between the weight average molecular weight (Mw) and the number average molecular weight (Mn) of the binder resin is 2 ≦ Mw / Mn ≦ 10, and the dry method according to claim 1 or 2, wherein With the electrostatic image developing toner, a high quality image with high gloss can be obtained, the productivity at the time of production is good, and the occurrence of sleeve contamination and filming can be suppressed even when used for a long time during image formation. Become.
[0134]
According to Claim 4, the acid value of the binder resin is 10 KOHmg / g or less, and the toner for developing a dry electrostatic image according to any one of Claims 1 to 3, wherein Image deterioration can be prevented.
[0135]
According to claim 5, the apparent viscosity of the binder resin measured by a flow tester is 10³5. The dry electrostatic image developing toner according to claim 1, wherein the temperature at which Pa · s is 95 to 120 ° C. is less likely to cause hot offset, and the gloss is good. Images can be obtained.
[0136]
According to claim 6, the repeating unit of the (A) sulfonic acid group-containing monomer of the resin charge control agent is 1 to 30% by weight based on the weight of the resin charge control agent, and the resin charge control agent has (B) electron attraction. The repeating unit of the aromatic monomer having a group is 1 to 80% by weight based on the weight of the resin charge control agent, and the repeating unit of the (C) acrylate monomer and / or methacrylate ester monomer of the resin charge control agent is resin. 10 to 80% by weight based on the weight of the charge control agent, and the repeating unit of the aromatic vinyl monomer (D) of the resin charge control agent is contained at a ratio of 0 to 30% by weight based on the weight of the resin charge control agent. The toner for developing a dry electrostatic image according to any one of claims 1 to 5, wherein the toner has a sufficient charge rising performance and a sufficient saturation charge, and can withstand temperature and humidity changes. Bed contamination, prevent the occurrence of photoconductor filming, it is possible to prevent a decrease in manufacturing time productivity.
[0137]
According to claim 7, the (B) aromatic monomer having an electron-withdrawing group of the resin charge control agent is a phenylmaleimide-substituted or phenylitaconimide-substituted compound substituted by a chlorine atom or a nitro group. According to the dry electrostatic image developing toner according to any one of claims 1 to 6, it is possible to obtain a toner having good chargeability and filming resistance.
[0138]
According to claim 8, the apparent viscosity of the resin charge control agent measured by a flow tester is 10%.⁴The temperature at which Pa · s is 85 to 110 ° C., according to the dry electrostatic image developing toner according to any one of claims 1 to 7, wherein the charge control agent has good dispersibility. In addition, the toner has good storage stability, does not stick in the pulverizing step at the time of production, does not have background contamination and toner scattering, and can provide a toner having good color development at the time of color toner color superposition.
[0139]
According to claim 9, the weight average molecular weight of the resin charge control agent is 5 × 10 5³~ 1 × 10⁵9. The dry electrostatic image developing toner according to claim 1, wherein the charge controlling agent is appropriately dispersed in the toner, and the charge is not reduced. No soiling and toner scattering, and good fixability and color development of the toner can be achieved.
[0140]
The dry electrostatic image according to any one of claims 1 to 9, wherein the resin charge control agent is contained in an amount of 0.1 to 20% by weight based on the toner particles. By the developing toner, it is possible to obtain a toner which is sufficiently charged and has a sufficient charge, and has no background stain on the image and no toner scattering.
[0141]
According to claim 11, the apparent viscosity of the binder resin measured by a flow tester is 10³The temperature at which Pa · s becomes T₁The apparent viscosity of the resin charge control agent measured by a flow tester is 10⁴The temperature at which Pa · s becomes T₂And T₁, T₂Is 0.9 <T₁/ T₂11. The dry electrostatic image developing toner according to any one of claims 1 to 10, wherein the toner has good chargeability and filming prevention property. Becomes possible.
[0142]
According to the twelfth aspect, the additive is 2.1 parts by weight or more of hydrophobically treated silica having a primary particle diameter of 0.01 to 0.03 μm or more based on 100 parts by weight of the base toner. 0.01 to 0.03 μm and specific surface area of 60 to 140 m²/ G of hydrophobically treated titanium oxide in an amount of 0.4 to 1.0 parts by weight. The chargeability becomes appropriate, and it becomes possible to prevent toner scattering and background contamination.
[0143]
According to the thirteenth aspect, the triboelectric charge amount of the toner can be stably controlled and maintained by the dry one-component developer comprising the toner for developing a dry electrostatic image according to the first aspect. Dry one-component development that maintains stable triboelectric charging with little environmental fluctuation, and is excellent in toner transportability, developability, transferability, and preservation, and does not generate abnormal images due to adhesion to photoconductors. Agent can be obtained.
[0144]
According to a fourteenth aspect, a dry two-component developer comprising the toner for developing a dry electrostatic image according to the first aspect and a carrier stably controls and maintains the triboelectric charge amount of the toner. Dry type, which can maintain stable triboelectric chargeability with little environmental fluctuation, and is excellent in toner transportability, developability, transferability, and storage stability, and does not generate abnormal images due to adhesion to photoreceptors. It becomes possible to obtain a component developer.
[0145]
According to the fifteenth aspect, a latent image forming step of forming a latent image on the latent image holding member, a developing step of developing the latent image using the developer on the developer carrier, and transferring the developed toner image An image forming method comprising: a transfer step of transferring onto a body; and a fixing step of heating and fixing a toner image on a transfer body, wherein the dry type one-component developer according to claim 13 is used as a developer. Depending on the forming method, it is possible to stably control and maintain the triboelectric charge amount of the toner, and to maintain stable triboelectric chargeability with little environmental fluctuation, and to transport, develop, transfer, fix, and store the toner. It is possible to obtain a vivid image with excellent properties and no background stain.
[0146]
According to claim 16, a container for holding the one-component developer according to claim 13, a container for replenishing the developer, an apparatus having the latent image forming step, an apparatus having the developing step, and the transfer step And an image forming apparatus having the above-described fixing step, the toner can stably control and maintain the triboelectric charge amount of the toner, and maintain stable triboelectric charging with little environmental fluctuation. In addition, the toner can be formed with excellent toner transportability, developability, transferability, and storage stability, and can be formed without generating an abnormal image due to adhesion to a photoreceptor.
[0147]
According to the seventeenth aspect, a latent image forming step of forming a latent image on the latent image holding member, a developing step of developing the latent image using the developer on the developer carrier, and transferring the developed toner image An image forming method comprising: a transfer step of transferring onto a body; and a fixing step of heating and fixing a toner image on a transfer body, wherein the dry two-component developer according to claim 14 is used as a developer. By the forming method, the amount of triboelectric charge of the toner can be stably controlled and maintained, and the stable triboelectric property with little environmental fluctuation can be maintained. It is possible to form an image which is excellent in storability and does not cause an abnormal image due to adhesion to a photoconductor.
[0148]
According to claim 18, a container for holding the dry two-component developer according to claim 14, a container for supplying the toner, an apparatus having the latent image forming step, an apparatus having the developing step, and the transfer step And an image forming apparatus having the above-described fixing step, the toner can stably control and maintain the triboelectric charge amount of the toner, and maintain stable triboelectric charging with little environmental fluctuation. In addition, the toner can be formed with excellent toner transportability, developability, transferability, and storage stability, and can be formed without generating an abnormal image due to adhesion to a photoreceptor.

Claims (18)

In a toner for developing a dry electrostatic image mainly containing at least a binder resin, a colorant, a charge control agent and an additive, the binder resin is composed of one or more polyester resins, and the polyester resin does not contain a THF-insoluble component. In the molecular weight distribution in gel permeation chromatography, the content of components having a molecular weight of 5 × 10 ² or less is 4% by weight or less, and a main peak is present in a region of a weight molecular weight of 3 × 10 ^{3 to} 9 × 10 ^3. The charge control agent comprises a resin charge control agent, and the resin charge control agent comprises at least (A) a sulfonic acid salt group-containing monomer, (B) an aromatic monomer having an electron withdrawing group, and (C) an acrylic monomer. Among the acid ester monomers and / or methacrylic acid ester monomers, and (D) the aromatic vinyl monomer, (A) to ( C) or (A) to (D) as constituent units, the resin charge control agent has a volume resistance of 9.5 to 11.5 Log Ω · cm, and the resin charge control agent has a weight average molecular weight of 1 × 10 ³ or less. Is 10% by weight or less, and the additive has a ratio of a hydrophobicized silica having a primary particle diameter of 0.01 to 0.03 μm to a silica having a primary particle diameter of 0.01 to 0.03 μm. And titanium oxide having a surface area of 60 to 140 m ² / g, which has been subjected to a hydrophobizing treatment. A toner for developing a dry electrostatic image, wherein a transmittance at 300 nm is 35% or more and a transmittance at 600 nm is 80% or more in a UV absorption method. 2. The toner according to claim 1, wherein the binder resin has an endothermic peak in DSC of 60 to 70 ° C. 3. The dry electrostatic image developing toner according to claim 1, wherein a ratio of a weight average molecular weight (Mw) to a number average molecular weight (Mn) of the binder resin is 2 ≦ Mw / Mn ≦ 10. The dry electrostatic image developing toner according to any one of claims 1 to 3, wherein the binder resin has an acid value of 10 KOHmg / g or less. The toner for developing a dry electrostatic image according to any one of claims 1 to 4, wherein the temperature at which the apparent viscosity of the binder resin measured by a flow tester is 10 ³ Pa · s is 95 to 120 ° C. . The repeating unit of the (A) sulfonate group-containing monomer of the resin charge control agent is 1 to 30% by weight based on the weight of the resin charge control agent, and the resin charge control agent (B) is an aromatic monomer having an electron-withdrawing group. The repeating unit is 1 to 80% by weight based on the weight of the resin charge control agent, and the repeating unit of the (C) acrylate monomer and / or methacrylate monomer of the resin charge control agent is based on the weight of the resin charge control agent. 2. The resin charge control agent according to claim 1, wherein the repeating unit of the aromatic vinyl monomer (D) is contained in an amount of 0 to 30% by weight based on the weight of the resin charge control agent. 6. The toner for developing a dry electrostatic charge image according to any one of items 5 to 5. 2. The resin charge control agent according to claim 1, wherein (B) the aromatic monomer having an electron-withdrawing group is a phenylmaleimide-substituted or phenylitaconimide-substituted compound substituted by a chlorine atom or a nitro group. 7. The toner for developing a dry electrostatic image according to any one of 6. The dry electrostatic image development according to any one of claims 1 to 7, wherein a temperature at which an apparent viscosity of the resin charge control agent by a flow tester becomes 10 ⁴ Pa · s is 85 to 110 ° C. For toner. 9. The dry electrostatic image developing toner according to claim 1, wherein the resin charge control agent has a weight average molecular weight of 5 × 10 ³ to 1 × 10 ^5. 10. The dry electrostatic image developing toner according to any one of claims 1 to 9, wherein the resin charge control agent is contained in an amount of 0.1 to 20% by weight based on the toner particles. When the temperature at which the apparent viscosity of the binder resin by a flow tester is 10 ³ Pa · s is T ₁ , and the temperature at which the apparent viscosity of the resin charge control agent by the flow tester is 10 ⁴ Pa · s is T ₂ , T 11. The dry electrostatic image developing toner according to claim ₁ , wherein T ₂ satisfies 0.9 <T ₁ / T ₂ <1.4. The above-mentioned additive is used in an amount of not less than 2.1 parts by weight of hydrophobically treated silica having a primary particle diameter of 0.01 to 0.03 μm with respect to 100 parts by weight of the base toner in a primary particle diameter of 0.01 to 0.03 μm. dry developing an electrostatic charge image according to any one of claims 1 to 11, characterized in that it comprises a hydrophobized titanium oxide having a specific surface area 60~140m ² / g 0.4~1.0 parts by weight For toner. A dry one-component developer comprising the dry electrostatic image developing toner according to claim 1. A dry two-component developer comprising the toner for developing a dry electrostatic image according to claim 1 and a carrier. A latent image forming step of forming a latent image on the latent image holding member, a developing step of developing the latent image using a developer on a developer carrier, and a transferring step of transferring the developed toner image onto a transfer member An image forming method comprising a fixing step of heating and fixing a toner image on a transfer member, wherein the dry one-component developer according to claim 13 is used as a developer. A container for holding the one-component developer according to claim 13, a container for replenishing the developer, an apparatus having the latent image forming step, an apparatus having the developing step, an apparatus having the transfer step, and the fixing step. An image forming apparatus comprising: A latent image forming step of forming a latent image on the latent image holding member, a developing step of developing the latent image using a developer on a developer carrier, and a transferring step of transferring the developed toner image onto a transfer member An image forming method, comprising: a fixing step of heating and fixing a toner image on a transfer body, wherein the dry two-component developer according to claim 14 is used as a developer. A container for holding the dry two-component developer according to claim 14, a container for replenishing the toner, an apparatus having the latent image forming step, an apparatus having the developing step, an apparatus having the transfer step, and the fixing step. An image forming apparatus comprising: