JP4067857B2 - Image forming method - Google Patents

Description

【００３１】
〔式(I) 中、Ａ、Ｂ、Ｃ、及びＤは各々独立して、置換基を有していてもよい芳香族環を示し、Ｑは、直接結合、又は２価の連結基を示す。〕
【００３２】
ここで、式(I) におけるＡ、Ｂ、Ｃ、及びＤの芳香族環としては、例えば、ベンゼン環、ナフタレン環、アントラセン環、フェナントレン環等が挙げられ、中で、ベンゼン環、又はナフタレン環が好ましく、ベンゼン環が特に好ましい。又、これらの芳香族環における置換基としては、例えば、炭化水素基、アルコキシ基、アルキルチオ基、ジアルキルアミノ基、ニトロ基、シアノ基、水酸基、ハロゲン原子等が挙げられ、中で、ハロゲン原子が好ましい。又、Ｑの２価の連結基としては、例えば、酸素原子、硫黄原子、アルキレン基、アルケニレン基、アルキルイミノ基等が挙げられ、中で、置換基を有していてもよい炭素数１〜４のアルキレン基、又は置換基を有していてもよい炭素数２〜４のアルケニレン基が好ましい。又、式(I) の化合物の金属塩又は金属錯体における金属としては、アルカリ金属、又はアルカリ土類金属が好ましく、カリウム、又はナトリウムが特に好ましい。
【００３３】
【化２】

【００３４】
〔式(II)中、Ｒ¹ 及びＲ² は各々独立して、置換基を有していてもよい炭素数１〜１２の炭化水素基、ハロゲン原子、又は水素原子を示し、Ｒ³ 及びＲ⁴ は各々独立して、置換基を有していてもよい炭素数１〜５の炭化水素基、又は水素原子を示し、ｎ及びｍは、０以上の整数であり、ｎ＋ｍは４〜１０である。〕
【００３５】
ここで、式(II)におけるＲ¹ 、Ｒ² 、Ｒ³ 、及びＲ⁴ としては、置換基を有していてもよい炭素数１〜５のアルキル基、又は水素原子が好ましく、Ｒ¹ 及びＲ² が置換基を有していてもよい炭素数３〜５のアルキル基であり、Ｒ³ 及びＲ⁴ が水素原子であるのが特に好ましい。又、ｎ＋ｍが６〜９であるのが好ましく、８であるのが特に好ましい。
【００３６】
【化３】

【００３７】
〔式(III) 中、Ｒ⁵ 及びＲ⁶ は各々独立して、置換基を有していてもよい炭素数１〜１２の炭化水素基、又は水素原子を示す。〕
【００３８】
ここで、式(III) におけるＲ⁵ 及びＲ⁶ としては、置換基を有していてもよい炭素数３〜５のアルキル基であるのが好ましい。又、式(III) の化合物の金属塩又は金属錯体における金属としては、２価又は３価の金属が好ましく、クロム、アルミニウム、又は亜鉛が特に好ましい。
【００３９】
【化４】

【００４０】
〔式(IV)中、Ｅ及びＦは各々独立して、置換基を有していてもよい芳香族環を示す。〕
【００４１】
ここで、式(IV)におけるＥ及びＦの芳香族環としては、例えば、ベンゼン環、ナフタレン環、アントラセン環、フェナントレン環等が挙げられ、中で、ベンゼン環又はアントラセン環が好ましく、ベンゼン環が特に好ましい。又、これらの芳香族環における置換基としては、例えば、炭化水素基、アルコキシ基、アルキルチオ基、ジアルキルアミノ基、ニトロ基、シアノ基、水酸基、ハロゲン原子等が挙げられるが、中で、無置換のものが好ましい。又、式(IV)の化合物の金属塩又は金属錯体における金属としては、２価又は３価の金属が好ましく、クロム、アルミニウム、又は亜鉛が特に好ましい。又、式(IV)の化合物の硼素錯体も好ましい。
【００４２】
【化５】

【００４３】
〔式(V) 中、Ｒ⁷ 、Ｒ⁸ 、Ｒ⁹ 、及びＲ¹⁰は各々独立して、置換基を有していてもよい炭素数１〜５の炭化水素基、ニトロ基、シアノ基、ハロゲン原子、又は水素原子を示し、Ｒ¹¹及びＲ¹²は各々独立して、Ｎ−フェニルカルバモイル基、又は水素原子を示し、Ｍは、３価の金属を示し、Ｘ⁺ は、プロトン、アンモニウムイオン、又はアルカリ金属イオンを示す。〕
【００４４】
ここで、式(V) におけるＲ⁷ 、Ｒ⁸ 、Ｒ⁹ 、及びＲ¹⁰は、それらの少なくとも一つがニトロ基、又は塩素原子であるのが好ましく、又、Ｍとしては、クロム、又は鉄が好ましく、Ｘ⁺ としては、プロトン、カリウムイオン、又はナトリウムイオンが好ましい。
【００４５】
尚、トナー粒子における前記帯電制御剤の含有割合は、前記バインダー樹脂１００重量部に対して０．０１〜１０重量部であるのが好ましく、０．１〜５重量部であるのが更に好ましい。
【００４６】
又、本発明において、トナー粒子は、更に、転写材への定着時の離型性等の改良のためにワックス類を含有しているのが好ましく、そのワックス類としては、従来公知の、例えば、低分子量ポリエチレン、低分子量ポリプロピレン、低分子量エチレン−プロピレン共重合体等のポリオレフィン系ワックス、パラフィン系ワックス、ステアリン酸エステル、ベヘン酸エステル、モンタン酸エステル等の長鎖脂肪族基を有するエステル系ワックス、水添ヒマシ油、カルナバワックス等の植物系ワックス、ジステアリルケトン等の長鎖アルキル基を有するケトン、アルキル基を有するシリコーン、ステアリン酸等の高級脂肪酸、長鎖脂肪族アルコール、ペンタエリスリトール等と長鎖脂肪酸との（部分）エステル体、オレイン酸アミド、ステアリン酸アミド等の高級脂肪酸アミド等が挙げられる。又、低分子量ポリテトラフルオロエチレン等も有用である。尚、本発明におけるこれらのワックス類としては、融点が５０〜１００℃であるのが好ましい。
【００４７】
尚、トナー粒子における前記ワックス類の含有割合は、前記バインダー樹脂１００重量部に対して０．１〜２５重量部であるのが好ましく、５〜１５重量部であるのが更に好ましい。
【００４８】
更に、本発明において、トナー粒子としては、トナーの粘着性、凝集性、流動性、帯電性、表面抵抗等の改質のために公知の各種内添剤、例えば、シリコーンオイル、シリコーンワニス等を含有していてもよい。
【００４９】
本発明におけるトナー粒子の製造方法としては、特に限定されるものではなく、例えば、前記着色剤、前記バインダー樹脂の粉粒体、及び前記帯電制御剤、前記ワックス類等を、例えば、タンブラーブレンダー、リボンブレンダー、Ｖ型ブレンダー、ヘンシェルミキサー、スーパーミキサー等の混合機により均一に混合した後、一軸又は二軸以上の押出機等の混練機により溶融混練してトナー粒子用樹脂組成物となし、該樹脂組成物を、例えば、ジョークラッシャー、ジャイレートリークラッシャー、ロールミル、ハンマーミル、フェザーミル等により粗粉砕或いは更に中粉砕して、平均粒径を通常約５０〜３，０００μｍ、好ましくは約５０〜５００μｍ程度の粗粒子とした後、該粗粒子を、例えば、ロールミル、ハンマーミル、ボールミル、ジェットミル等により数１０μｍ以下程度の粉体に微粉砕し、得られた粉体を、例えば、慣性分級方式のエルボジェット、遠心力分級方式のミクロプレックス、ＤＳセパレータ等の分級機により分級して規定粒度のトナー粒子とした後、必要に応じてメカノフュージョン法やサーフュージョン法等の球形化手段を施す粉砕法、或いは、前記バインダー樹脂成分モノマーを、前記着色剤、及び前記帯電制御剤、前記ワックス類等の存在下に懸濁重合させる懸濁重合法、前記バインダー樹脂成分モノマーを乳化重合させたエマルジョンを、前記着色剤、及び前記帯電制御剤、前記ワックス類等の存在下に攪拌して乳化粒子を凝集（会合）させる乳化重合凝集法等を挙げることができる。
【００５０】
これらの中で、本発明においては、乳化重合凝集法が好ましく、その際、前記ワックス類の微粒子を、前記バインダー樹脂成分モノマーの乳化重合におけるシードとして用いてシード重合するのが好ましい。
【００５１】
本発明におけるトナーは、前記トナー粒子の表面が、無機質微粉末と有機質微粉末とで被覆されてなるものであり、その無機質微粉末としては、従来公知の、例えば、アルミナ、シリカ、チタニア、酸化亜鉛、酸化ジルコニウム、酸化セリウム、タルク、ハイドロタルサイト等の金属酸化物・水酸化物、チタン酸カルシウム、チタン酸ストロンチウム、チタン酸バリウム等のチタン酸金属塩、窒化チタン、窒化珪素等の窒化物、炭化チタン、炭化珪素等の炭化物、及び、フェライト、マグネタイト等の磁性粉等が、又、その有機質微粉末としては、従来公知の、例えば、スチレン樹脂、アクリル樹脂、ベンゾグアナミン樹脂、メラミン樹脂等の樹脂、及び、例えば、オレイン酸カルシウム、オレイン酸亜鉛、ステアリン酸カルシウム、ステアリン酸亜鉛等の高級脂肪酸金属塩等が、それぞれ挙げられる。これらの中で、無機質微粉末としてはアルミナ、シリカ、チタニアが好ましく、又、有機質微粉末としてはスチレン樹脂、アクリル樹脂が好ましい。
【００５２】
又、これら微粉末の平均粒径は、無機質微粉末においては０．０１〜１μｍであるのが好ましく、０．０１〜０．５μｍであるのが更に好ましい。又、有機質微粉末においては、０．０５〜３μｍであるのが好ましく、０．１〜１μｍであるのが更に好ましい。尚、ここで、平均粒径は、透過型電子顕微鏡により測定した、任意の粒子５００個の粒径の算術平均値として求めたものであり、円形でない場合には、画像処理による投影像の面積と同等の円の直径をもって粒径とした。
【００５３】
又、無機質微粉末としては、例えば、シランカップリング剤、又はシリコーンオイル等で表面処理されたものが好ましく、それにより、疏水化度が５０以上であるのが好ましく、６０以上であるのが更に好ましい。尚、ここで、疏水化度は、精秤した試料０．２０ｇをビーカーに採取し、純水５０ｍｌを加え、マグネチックスターラーで攪拌しながら液面上にメタノールを注入し、液面上に試料が認められなくなった時点におけるメタノールの注入量から、以下の式により算出したものである。
疏水化度＝〔メタノール注入量／（５０＋メタノール注入量）〕×１００
【００５４】
そして、本発明においては、前記無機質微粉末種〔Ｎ_I 〕が２〜５種、前記有機質微粉末種〔Ｎ_O 〕が１〜３種であって、前記トナー粒子１００重量部に対するそれらの無機質微粉末の合計重量部〔Ｗ_I 〕、及び有機質微粉末の合計重量部〔Ｗ_O 〕、並びに、それらの無機質微粉末の各平均粒径の合計をＮ_I で除した算術平均粒径〔Ｄ_I 〕、及び有機質微粉末の各平均粒径の合計をＮ_O で除した算術平均粒径〔Ｄ_O 〕が、下記式（１）、（２）、及び（３）の関係を有することを必須とする。
【００５５】
２．０≦Ｗ_１≦５．０ （１）
０．０１≦Ｗ_０≦２．０ （２）
１．２≦（Ｄ_０×Ｗ_０）／（Ｄ_１×Ｗ_１ ）≦５ （３）
【００５６】
前記無機質微粉末の合計重量部〔Ｗ_I 〕が前記範囲未満、及び、前記有機質微粉末の合計重量部〔Ｗ_O 〕が前記範囲超過では、トナーとしての流動性が低下することとなり、一方、前記無機質微粉末の合計重量部〔Ｗ_I 〕が前記範囲超過では、感光体のフィルミングが生じることとなり、又、前記有機質微粉末の合計重量部〔Ｗ_O 〕が前記範囲未満では、トナーとしての帯電が不安定となり、いずれにおいても、得られる画像の画質が低下することとなる。又、前記〔（Ｄ_O ×Ｗ_O ）／（Ｄ_I ×Ｗ_I ）〕の値が前記範囲外でも、高画質の画像を得ることが困難となる。
【００５７】
尚、本発明において、前記トナー粒子表面を前記無機質微粉末と前記有機質微粉末とで被覆しトナーとなすには、前記トナー粒子に、前記無機質微粉末及び前記有機質微粉末とを添加し、例えばヘンシェルミキサー等の混合機により均一に攪拌、混合することによりなされる。
【００５８】
本発明におけるトナーは、コールター社製マルチサイザーを用いて測定した粒度分布として、５０％累積頻度における体積平均粒径〔Ｄ_v （μｍ）〕の５０％累積頻度における個数平均粒径〔Ｄ_n （μｍ）〕に対する比〔Ｄ_v ／Ｄ_n 〕が、１．０〜１．２５であるのが好ましく、１．０〜１．２０であるのが更に好ましい。更に、粒径５．０μｍ以下の粒子の割合が１０個数％以上、８．０〜１２．７μｍの粒子の割合が４０個数％以下、１６．０μｍ以上の粒子の割合が２個数％以下で、且つ、５０％累積頻度における体積平均粒径〔Ｄ_v 〕が４〜１０μｍであるのが特に好ましい。
【００５９】
又、シスメックス社製フロー式粒子像分析装置「ＦＰＩＡ−２１００」を用いて、下記式により求められる円形度の５０％累積頻度における円形度が、０．９２〜１．０を有するものであるのが好ましく、０．９４〜１．０を有するものであるのが更に好ましい。
円形度＝粒子投影像の面積と同面積の円の周長／粒子投影像の周長
【００６０】
ここで、「円形度の５０％累積頻度における円形度」とは、前記式により求められる円形度０〜１を横軸としその累積頻度０〜１００％を縦軸とした分布曲線において、その５０％累積頻度における円形度を言う。
【００６１】
又、ＵＢＭ社製動的粘弾性測定装置「ＭＲ−５００」を用いて、パラレルプレートにて周波数１Ｈｚの条件下で測定した貯蔵弾性率が、単色用トナーとしては１５０℃で測定した値として、又、フルカラー用トナーとしては１２０℃で測定した値として、１％歪みでの貯蔵弾性率〔Ｇ' _1%（Ｐａ）〕と３０％歪みでの貯蔵弾性率〔Ｇ'_30%（Ｐａ）〕とが、下記式（４）及び（５）の関係を有するものであるのが好ましい。
【００６２】
１．０×１０² ≦Ｇ' _1%≦１．０×１０⁴ （４）
１．０≦Ｇ' _1%／Ｇ'_30%≦１０．０ （５）
【００６３】
本発明におけるトナーとしては、トナーを磁力により静電潜像部に搬送するためのキャリアとしてのフェライト、マグネタイト等の磁性粉を共存させる磁性二成分用、又は、それらの磁性粉をトナー中に含有させた磁性一成分用、或いは、トナーに磁性粉を用いない非磁性一成分用のいずれでもよいが、非磁性一成分用、又は磁性一成分用であるのが好ましい。尚、キャリアとしての磁性粉としては、例えば、ポリ弗化ビニリデン、ポリテトラフルオロエチレン等の弗素樹脂等で表面処理されたものが好ましい。
【００６４】
本発明の画像形成方法を、非磁性一成分トナーを用いた場合について図面に基づいて説明すると、図１は、本発明の画像形成方法に用いられる画像形成装置の一実施例を示す概略図であり、１は感光体、１ａは導電性支持体、１ｂは感光層、２は帯電装置、３は露光装置、４は現像装置、４ａは現像ローラ、４ｂはトナー供給ローラ、４ｃはブレード、４ｄはアジテータ、５は転写装置、６はクリーニング装置、７は定着装置、７ａは下部定着部材、７ｂは上部定着部材、７ｃは加熱装置、Ｔはトナー、Ｐは記録紙であり、帯電装置２、露光装置３、現像装置４、転写装置５、及びクリーニング装置６は、感光体１の外周面に沿って配置されている。
【００６５】
ここで、感光体１は、アルミニウム等の導電性金属製であって、回転駆動機構（図示せず）によって回動可能とされたドラム状支持体１ａと、その外周面に形成された感光層１ｂとからなる。又、帯電装置２は、感光体１の外周面に当接して配置された、スコロトロン帯電器、ローラ帯電器等からなり、感光体１の表面を所定電位に一様に帯電する。又、露光装置３は、ＬＥＤ、レーザー光等の光源照射装置からなり、感光体１の感光層１ｂに静電潜像を形成させる。
【００６６】
又、現像装置４は、鉄、ステンレス鋼、アルミニウム、ニッケル等の金属製ロール、或いは外周面にシリコン樹脂、弗素樹脂、ウレタン樹脂等を被覆した金属製ロール等からなり、感光体１の外周面に当接して回転駆動機構（図示せず）によって回動可能に配置され、その外周面に担持したトナーＴを感光体１の外周面に接触させる現像ローラ４ａと、導電性スポンジ製等であって、現像ローラ４ａに当接して回転駆動機構（図示せず）によって回動可能に配置され、現像装置４内に貯留されたトナーＴを担持して現像ローラ４ａに供給するトナー供給ローラ４ｂ、及び、シリコン樹脂、ウレタン樹脂等の樹脂製、或いは、ステンレス鋼、アルミニウム、銅、真鍮、燐青銅等の金属製、或いは、表面に樹脂を被覆した金属製等であって、現像ローラ４ａの外周面をバネ等によって押圧して配置され、トナー供給ローラ４ｂによって現像ローラ４ａの外周面に供給されたトナーＴの層厚を規制するブレード４ｃ、並びに、回転駆動機構（図示せず）によって回動可能とされた羽根形状であって、現像装置４内に貯留されたトナーＴを攪拌するアジテータ４ｄとから構成される。
【００６７】
又、転写装置５は、感光体１の外周面に当接して配置された、転写チャージヤー、転写ローラ、転写ベルト等からなり、トナーＴの帯電電位とは逆極性で所定電圧が印加され、感光体１に形成されたトナー像を記録紙Ｐに転写する。又、クリーニング装置６は、ブレード、ファーブラシ等のクリーニング部材からなり、感光体１の外周面に残留するトナーＴを掻き落とす。又、定着装置７は、ステンレス鋼、アルミニウム等の金属製素管にシリコン樹脂、弗素樹脂等を被覆したローラ、或いはそれら金属製シートに樹脂を被覆したシート等からなる下部定着部材７ａと、同様の材質からなり、下部定着部材７ａに圧接して設けられた上部定着部材７ｂとで構成され、いずれかの部材７ａ、７ｂ（図面では上部定着部材７ｂ）には加熱装置７ｃが内設されており、記録紙Ｐ上のトナー像におけるトナーＴを溶融状態まで加熱し、記録紙Ｐ上に定着させる。
【００６８】
そして、本発明の画像形成方法において、導電性支持体１ａ上に、電荷発生剤として前記Ｙ型オキシチタニウムフタロシアニンを含有する感光層１ｂを形成した感光体１の表面を、帯電装置２によって所定電位に一様に帯電させ、次いで、露光装置３によって露光せしめ、露光された部分の電荷を消散させて、感光層１ｂに静電潜像を形成し、露光されていない部分に、現像装置４の現像ローラ４ａに担持された荷電トナーＴを付着させることによって、その静電潜像を可視化させて現像し、得られたトナー像を、転写装置５によって記録紙Ｐに転写し、転写された記録紙Ｐ上のトナーＴを定着装置７によって加熱、加圧して記録紙Ｐに定着させるものである。尚、感光体１は、クリーニング装置６によりその外周面をクリーニングされ、前記と同様の操作が繰り返される。
【００６９】
本発明の画像形成方法は、画像濃度が高く、高画質の画像を形成することができ、特に小型、高速の画像形成装置において、又、７５０〜８５０ｎｍの波長領域の感度が高いことから、特に半導体レーザーを露光光源とする画像形成装置において、好適に使用される。
【００７０】
【実施例】
以下、本発明を実施例により更に具体的に説明するが、本発明はその要旨を越えない限り、以下の実施例に限定されるものではない。尚、以下の実施例及び比較例において用いた感光体及びトナー粒子の各製造例、並びに、無機質微粉末及び有機質微粉末を以下に示す。
【００７１】
＜感光体の製造例１＞
直径３０ｍｍの円筒状アルミニウム支持体上に、電荷発生物質として、ＣｕＫα線によるＸ線回折スペクトルにおいてブラッグ角（２θ±０．２°）２７．３°、２４．２°、９．７°、及び７．４°に回折ピークを有するＹ型オキシチタニウムフタロシアニン２００重量部、及びバインダー樹脂として、ポリビニルブチラール（電気化学工業社製「デンカブチラール♯６０００Ｃ」）１００重量部を含む塗布液を塗布し、乾燥させて膜厚０．４μｍの電荷発生層を形成し、その上に、電荷輸送物質として、Ｎ−メチル−３−カルバゾールカルバルデヒドジフェニルヒドラゾン７０重量部、及びバインダー樹脂として、ポリカーボネート樹脂（三菱化学社製「ノバレックス８０２５Ａ」）１００重量部、並びにｐ−ニトロベンゾイルオキシベンザルマロノニトリル２重量部を含む塗布液を塗布し、乾燥させて膜厚１５μｍの電荷輸送層を形成することにより、積層型の感光層を有する感光体を製造した。
【００７２】
＜感光体の製造例２＞
電荷発生物質として、ＣｕＫα線によるＸ線回折スペクトルにおいてブラッグ角（２θ±０．２°）２２．３°、１７．３°、１６．７°、９．１°、及び７．５°に回折ピークを有するＸ型無金属フタロシアニンを用いた外は、前記製造例１と同様として感光体を製造した。
【００７３】
＜トナー粒子の製造例１＞
着色剤として、シアン顔料（ピグメントブルー１５：３）の４０重量％マスターバッチ１０重量部、バインダー樹脂として飽和ポリエステル樹脂１００重量部、帯電制御剤として前記一般式(IV)の化合物であるベンジル酸の硼素錯体（日本カーリット社製「ＬＲ−１４７」）１重量部、及び融点８０℃のパラフィンワックス５重量部を、ヘンシェルミキサーで混合した後、二軸押出機を用いて溶融混練することによりトナー用樹脂組成物を作製し、冷却後、ハンマーミルにより粗粉砕し、次いで、超音速ジェツトミルにより微粉砕し、得られた粉体を風力分級機により分級し、更に、サーフュージョン法で球形化処理を施してトナー粒子を製造した。
【００７４】
＜トナー粒子の製造例２＞
パラフィンワックスを用いなかったこと、及び、サーフュージョン法での球形化処理を施さなかったこと、の外は、前記トナー粒子の製造例１と同様にして、トナー粒子を製造した。
【００７５】
＜トナー粒子の製造例３＞
ペンタエリスリトールのテトラステアリン酸エステルを主成分とするエステルワックス（日本油脂社製「ユニスターＨ４７６０」３０重量部を、ドデシルベンゼンスルホン酸ナトリウム１．６７重量部と共に、脱塩水６８．３３重量部に加えて、高圧剪断下で乳化することにより、平均粒径０．２６μｍのエステルワックス微粒子のエマルジョンを作製し、次いで、内容積３リットルの反応器に、前記で得られたエステルワックスのエマルジョン５３．１重量部と脱塩水４０６重量部を仕込み、窒素気流下で９０℃に昇温した後、８％過酸化水素水溶液１．６重量部と８％アスコルビン酸水溶液１．６重量部を添加し、引き続いて、スチレン８０重量部、ブチルアクリレート２０重量部、アクリル酸１重量部、ヘキサンジオールジアクリレート０．８重量部、及び連鎖移動剤としてのトリクロロブロモメタン０．４５重量部と２−メルカプトエタノール０．０１重量部、の混合物、並びに、１０重量％ドデシルベンゼンスルホン酸ナトリウム水溶液１重量部と脱塩水２５重量部との乳化剤水溶液を５時間かけて加えると共に、８％過酸化水素水溶液９重量部と８％アスコルビン酸水溶液９重量部を６時間かけて加えて、攪拌下にエステルワックス微粒子をシードとして乳化共重合させ、冷却することにより、スチレン−ブチルアクリレート−アクリル酸主体の共重合体の一次粒子エマルジョンを得た。次いで、内容積１リットルの反応器に、前記で得られた重合体一次粒子エマルジョンを固形分として１００重量部と１０重量％ドデシルベンゼンスルホン酸ナトリウム水溶液０．５重量部を仕込み、均一に混合した後、着色剤としてのシアン顔料（ピグメントブルー１５：３）の３５重量％水分散液を固形分として６．７重量部を添加し、均一に混合し、引き続いて、硫酸アルミニウムを水溶液として０．６重量部滴下し、攪拌下に２０分かけて５０℃に昇温して１時間保持し、更に、６分かけて５３℃に昇温し、体積平均粒径が７．１μｍとなった時点で、再度、硫酸アルミニウムを水溶液として０．０７重量部滴下し、攪拌下に１０分かけて５５℃に昇温して３０分間保持し、更に、１０重量％ドデシルベンゼンスルホン酸ナトリウム水溶液３重量部を添加し、攪拌下に３５分かけて９５℃に昇温して３．５時間保持し、冷却、濾過、水洗、乾燥することにより、前記一次粒子凝集体としてのトナー粒子を製造した。
【００７６】
＜無機質微粉末＞
（１）平均粒径０．０４μｍ、疏水化度７０のシリカ。
（２）平均粒径０．０１５μｍ、疏水化度６０のシリカ。
（３）平均粒径０．０１２μｍ、疏水化度７０のシリカ。
（４）平均粒径０．０１５μｍ、疏水化度７０のチタニア。
＜有機質微粉末＞
（１）平均粒径０．３μｍのアクリル樹脂ビーズ。
（２）平均粒径０．２μｍのスチレン樹脂ビーズ。
【００７７】
実施例１〜３
前記製造例１のトナー粒子１００重量部に、次表１に示す無機質微粉末及び有機質微粉末を添加し、ヘンシェルミキサーで攪拌、混合することにより各トナーを製造した。
【００７８】
得られたトナーは、コールター社製マルチサイザーを用いて測定した粒度分布として、体積平均粒径〔Ｄ_v 〕の個数平均粒径〔Ｄ_n 〕に対する比〔Ｄ_v ／Ｄ_n 〕が、１．１６であり、又、粒径５．０μｍ以下の粒子の割合が１２．２個数％、８．０〜１２．７μｍの粒子の割合が９．９個数％、１６．０μｍ以上の粒子の割合が０．３個数％で、且つ、体積平均粒径〔Ｄ_v 〕が７．９μｍ、又、シスメックス社製フロー式粒子像分析装置「ＦＰＩＡ−２１００」を用いて測定した円形度が０．９３であり、又、ＵＢＭ社製動的粘弾性測定装置「ＭＲ−５００」を用いて、パラレルプレートにて周波数１Ｈｚの条件下、１２０℃で測定した、１％歪みでの貯蔵弾性率〔Ｇ' _1%〕が５．８×１０³ Ｐａ、３０％歪みでの貯蔵弾性率〔Ｇ'_30%〕が２．９×１０³ Ｐａ、Ｇ' _1%／Ｇ'_30%が２．０のものであった。
【００７９】
引き続いて、図１に示される画像形成装置を用い、前記製造例１の感光体の感光層に形成された静電潜像を前記の各トナーにより現像する画像形成を、温度２５℃、相対湿度６０％の環境下で実施し、初期、及び５，０００枚実写後に得られた各記録紙上の画像の画像濃度、解像度、及び階調性等の画像特性について、１０名のパネリストによる画質の「良好」、「不良」の判定を行い、その結果を以下の基準で評価し、結果を次表１に示した。
【００８０】
◎；良好と判断した人数１０名。
○；良好と判断した人数９名。
△；良好と判断した人数５〜８名。
×；良好と判断した人数４名以下。
【００８１】
実施例４
前記製造例３のトナー粒子１００重量部に次表１に示す無機質微粉末及び有機質微粉末を添加し、ヘンシェルミキサーで攪拌、混合することにより製造したトナーを用い、実施例１におけると同様にして、画像形成し、その画像特性を評価し、結果を次表１に示した。
【００８２】
尚、得られたトナーは、コールター社製マルチサイザーを用いて測定した粒度分布として、体積平均粒径〔Ｄ_v 〕の個数平均粒径〔Ｄ_n 〕に対する比〔Ｄ_v ／Ｄ_n 〕が、１．１８であり、又、粒径５．０μｍ以下の粒子の割合が１２．０個数％、８．０〜１２．７μｍの粒子の割合が１６．１個数％、１６．０μｍ以上の粒子の割合が０．３個数％で、且つ、体積平均粒径〔Ｄ_v 〕が７．５μｍ、又、シスメックス社製フロー式粒子像分析装置「ＦＰＩＡ−２１００」を用いて測定した円形度が０．９５であり、又、ＵＢＭ社製動的粘弾性測定装置「ＭＲ−５００」を用いて、パラレルプレートにて周波数１Ｈｚの条件下、１２０℃で測定した、１％歪みでの貯蔵弾性率〔Ｇ' _1%〕が４．３×１０³ Ｐａ、３０％歪みでの貯蔵弾性率〔Ｇ'_30%〕が１．９×１０³ Ｐａ、Ｇ' _1%／Ｇ'_30%が２．３のものであった。
【００８３】
比較例１
前記製造例２のトナー粒子１００重量部に次表１に示す無機質微粉末及び有機質微粉末を添加し、ヘンシェルミキサーで攪拌、混合することにより製造したトナーを用い、実施例１におけると同様にして、画像形成し、その画像特性を評価し、結果を次表１に示した。
【００８４】
尚、得られたトナーは、コールター社製マルチサイザーを用いて測定した粒度分布として、体積平均粒径〔Ｄ_v 〕の個数平均粒径〔Ｄ_n 〕に対する比〔Ｄ_v ／Ｄ_n 〕が、１．２９であり、又、粒径５．０μｍ以下の粒子の割合が９．８個数％、８．０〜１２．７μｍの粒子の割合が２０．８個数％、１６．０μｍ以上の粒子の割合が３．３個数％で、且つ、体積平均粒径〔Ｄ_v 〕が７．８μｍ、又、シスメックス社製フロー式粒子像分析装置「ＦＰＩＡ−２１００」を用いて測定した円形度が０．９１であり、又、ＵＢＭ社製動的粘弾性測定装置「ＭＲ−５００」を用いて、パラレルプレートにて周波数１Ｈｚの条件下、１２０℃で測定した、１％歪みでの貯蔵弾性率〔Ｇ' _1%〕が１１．８×１０³ Ｐａ、３０％歪みでの貯蔵弾性率〔Ｇ'_30%〕が７．０×１０³ Ｐａ、Ｇ' _1%／Ｇ'_30%が１．７のものであった。
【００８５】
【表１】

【００８６】
【発明の効果】
本発明によれば、感光体の感光層に形成された静電潜像をトナーにより現像して画像を形成するにおいて、画像濃度が高く、高画質の画像を形成することができ、特に小型、高速の画像形成装置において好適に用いられる画像形成方法を提供することができる。
【図面の簡単な説明】
【図１】 本発明の画像形成方法に用いられる画像形成装置の一実施例を示す概略図である。
【符号の説明】
１ ；感光体
１ａ；導電性支持体
１ｂ；感光層
２ ；帯電装置
３ ；露光装置
４ ；現像装置
４ａ；現像ローラ
４ｂ；トナー供給ローラ
４ｃ；ブレード
４ｄ；アジテータ
５ ；転写装置
６ ；クリーニング装置
７ ；定着装置
７ａ；下部定着部材
７ｂ；上部定着部材
７ｃ；加熱装置
Ｔ ；トナー
Ｐ ；記録紙[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an image forming method in an image forming apparatus such as an electrophotographic copying machine or printer, and more specifically, forms an image by developing an electrostatic latent image formed on a photosensitive layer of a photoreceptor with toner. The present invention relates to an image forming method that can form a high-quality image with a high image density, and is preferably used in a small and high-speed image forming apparatus.
[0002]
[Prior art]
Conventionally, as an electrophotographic image forming method, a photosensitive layer formed on a conductive support is uniformly charged, and then exposed to dissipate the charge of the exposed portion. The electrostatic latent image is formed, and the electrostatic latent image is visualized and developed by attaching a charged toner to an unexposed portion, and the obtained visible image is transferred to a transfer material such as recording paper. In general, image forming apparatuses such as copying machines and printers are widely used in which a visible image is fixed on a transfer material by heating, pressing, or the like.
[0003]
On the other hand, along with the recent downsizing and speeding up of the apparatus, the photoreceptor is required to shorten the time from exposure to development and the time from charge elimination to charging, and the toner is charged optimally for development. There is a need to shorten the time to reach the quantity.
[0004]
On the other hand, various image forming methods including improvements on the photoreceptor and the toner surface have been studied, but in any case, it takes time for the potential of the photoreceptor to be attenuated by exposure. Regarding problems such as fogging, memory, etc., it takes time for the toner to reach the desired charge amount, the resulting image has insufficient density, fogging, scattering, memory, etc. It has not yet been able to sufficiently satisfy market demands, and there is a strong demand for high image density, high resolution, high gradation, and other image quality that solve these problems. .
[0005]
[Problems to be solved by the invention]
The present invention has been made in view of the above-described prior art, and accordingly, the present invention develops an electrostatic latent image formed on a photosensitive layer of a photoreceptor with toner to form an image. An object of the present invention is to provide an image forming method that can form a high-density image with high density, and that is preferably used in a small and high-speed image forming apparatus.
[0006]
[Means for Solving the Problems]
As a result of intensive studies to solve the above problems, the inventor of the present invention contains a specific charge generating agent in the photosensitive layer of the photosensitive member, and uses inorganic fine powder and organic fine powder as specific additives for the external additive of the toner. The present invention has been completed by finding out that the above-mentioned object can be achieved by using together under the above, that is, the present invention is an image forming method for developing an electrostatic latent image formed on a photosensitive layer of a photoreceptor with toner. The photosensitive layer contains, as a charge generator, oxytitanium phthalocyanine having a maximum diffraction peak at a Bragg angle (2θ ± 0.2 °) of 27.3 ° in the X-ray diffraction spectrum, and the toner has a toner particle surface. it is coated with the inorganic fine powder and organic fine powder, the inorganic fine powder species [N _I] is 2 to 5 species, organic fine powders species [N _O] is a 1-3 type, toner particles 100 The total weight of the end thereof of the inorganic fine powder to the amount unit [W _I], and organic total parts by weight of fine powder [W _O], and the sum of the average particle size of the powder their inorganic fine powder divided by N _I The arithmetic average particle size [D _I ] and the arithmetic average particle size [D _O ] obtained by dividing the total average particle size of the organic fine powder by N 2 _O are the following formulas (1), (2), and (3) An image forming method having the relationship
[0007]
2.0 ≦ W ₁ ≦ 5.0 (1)
0.01 ≦ W ₀ ≦ 2.0 (2)
1.2 ≦ (D ₀ × W ₀ ) / (D ₁ × W ₁ ) ≦ 5 (3)
[0008]
DETAILED DESCRIPTION OF THE INVENTION
In the image forming method of the present invention, the photosensitive member has a photosensitive layer formed on a conductive support, and the conductive support is not particularly limited. For example, aluminum, stainless steel, nickel Metals such as copper, zinc, indium, silver and gold, resin films such as polyester resin, glass, paper and other insulating substrates such as aluminum, nickel, copper, zinc, palladium and other metals, tin oxide, oxidation Conventionally used is a cylindrical shape made of a laminated body provided with a vapor deposition layer such as a metal oxide such as indium, or a cylindrical shape with a sheet shape or belt shape covering the outer periphery of the drum. Things. In addition, the thickness as a metal sheet in that case is about 20-500 micrometers normally, and the thickness as a metal vapor deposition layer is about about 400-1,000 mm normally.
[0009]
The photosensitive layer formed on the conductive support may be a single layer type in which a charge generation material and a charge transport material are dispersed in a binder resin, or a charge generation material is dispersed in a binder resin. The stacked layer may be any one of a layered type including a charge generation layer and a charge transport layer in which a charge transporting material is dispersed in a binder resin, but the latter layered type is preferred.
[0010]
In the present invention, the charge generation material of the photosensitive layer must contain oxytitanium phthalocyanine having a maximum diffraction peak at a Bragg angle (2θ ± 0.2 °) of 27.3 ° in the X-ray diffraction spectrum, If the photosensitive layer does not contain the oxytitanium phthalocyanine, the object of the present invention cannot be achieved.
[0011]
Here, this oxytitanium phthalocyanine is a crystalline oxytitanium phthalocyanine having a maximum diffraction peak at a Bragg angle (2θ ± 0.2 °) of 27.3 ° in an X-ray diffraction spectrum by CuKα ray by the Bragg-Brentano concentration method. For example, FIG. 2 of JP-A-62-67094 (referred to as “Type II” in the same publication), FIG. 1 of JP-A-2-8256, Electrophotographic Society of Japan Vol. 92, No. 3 (issued in 1990), pages 250-258 (referred to as “Y-type” in the same magazine), etc., and has a maximum diffraction peak of 27.3 °. There are also diffraction peaks at 24.2 °, 9.7 °, and 7.4 °. In the present invention, the ratio of the area at the diffraction peak of 24.2 °, 9.7 °, and 7.4 ° to the area at the maximum diffraction peak of 27.3 ° is preferably 40% or less. Hereinafter, this oxytitanium phthalocyanine may be referred to as “Y-type oxytitanium phthalocyanine”.
[0012]
In the present invention, the photosensitive layer may contain a charge generation material other than the Y-type oxytitanium phthalocyanine as a charge generation material, and the charge generation material may be a conventionally known, for example, α-type oxyoxygen. Titanium-containing phthalocyanine compounds such as titanium phthalocyanine and β-type oxytitanium phthalocyanine, and alloys thereof such as selenium and selenium-tellurium alloys, metal sulfides such as arsenic selenide, zinc sulfide, cadmium sulfide, and antimony sulfide, zinc oxide , Metal oxides such as titanium oxide, inorganic photoconductive substances such as silicon-based materials such as amorphous silicon, phthalocyanines, anthraquinones, monoazo, bisazo, trisazo, polyazo, cyanine, perinone other than the above Perylene, quinacridone, polycyclic quinone, piliri And organic photoconductive substances such as various dyes such as um, thiapyrylium, indigo, thioindigo, anthanthrone, and pyranthrone.
[0013]
When a charge generation material other than the Y-type oxytitanium phthalocyanine is contained, when it is only the titanium-containing phthalocyanine compound, the proportion of the Y-type oxytitanium phthalocyanine in the total charge generation material is usually 30% by weight or more. It is preferably 50% by weight or more, and more preferably 70% by weight or more. When the charge generation material other than the titanium-containing phthalocyanine compound is contained, the proportion of Y-type oxytitanium phthalocyanine in the total charge generation material is usually 40% by weight or more and 60% by weight or more. Preferably, it is 80% by weight or more.
[0014]
Further, the charge transport material of the photosensitive layer is not particularly limited, and conventionally known organic polymer compounds such as polyacenaphthylene, polyvinyl anthracene, polyvinyl pyrene, polyvinyl carbazole, styrene, stilbene, etc. Aromatic hydrocarbon compounds and derivatives thereof, quinone compounds such as benzoquinone, naphthoquinone, anthraquinone, diphenoquinone and derivatives thereof, nitrogen-containing compounds such as aryl-substituted amines and aryl-substituted hydrazones and derivatives thereof, carbazole, acridine, pyrazoline, imidazole, benzimidazole , Nitrogen-containing heterocyclic compounds such as imidazolidine, imidazolone, phenazine, triazole and derivatives thereof, and nitrogen-containing sulfur-containing heterocyclic compounds such as thiazole, thiadiazole, benzothiazole and derivatives thereof Oxazole, nitrogen-containing oxygen-containing heterocyclic compounds such as oxadiazole and organic low molecular weight compound derivatives thereof, and the like.
[0015]
Further, the binder resin of the photosensitive layer is not particularly limited, and conventionally known, for example, styrene, butadiene, acrylic acid, methacrylic acid, acrylic ester, methacrylic ester, acrylonitrile, vinyl acetate, vinyl chloride, Examples thereof include homopolymers or copolymers of vinyl compounds such as vinyl alcohol, vinyl butyral, and vinyl pyrrolidone, saturated polyester resins, polycarbonate resins, polyamide resins, polyarylate resins, and polysulfone resins.
[0016]
The content ratio of the charge generation material, the charge transport material, and the binder resin in the photosensitive layer is 0.5 to 500 parts by weight of the binder resin with respect to 100 parts by weight of the charge generation material in the stacked charge generation layer. It is preferable that it is 20 to 300 parts by weight. In the multilayer charge transport layer, the binder resin is preferably 100 to 300 parts by weight, more preferably 150 to 250 parts by weight with respect to 100 parts by weight of the charge transport material.
[0017]
In the present invention, additives such as a plasticizer, an antioxidant, a heat stabilizer, an ultraviolet absorber, an antistatic agent, a lubricant, a release agent, and a flame retardant are added to the photosensitive layer as necessary. It may be.
[0018]
Further, an undercoat layer may be provided between the conductive support and the photosensitive layer, and the undercoat layer is made of a metal such as alumina, silica, titania, iron oxide, zinc oxide, zirconium oxide or the like. Fine powders of oxide, calcium titanate, metal titanate such as strontium titanate and barium titanate, nitrides such as titanium nitride and silicon nitride, carbides such as titanium carbide and silicon carbide are usually polyacrylic acid , Dispersed in a binder resin such as polyvinyl alcohol, polyvinyl butyral, polyvinyl pyrrolidone, polyurethane resin, polyamide resin, cellulose, casein, epoxy resin, phenol resin, melamine resin, and the fine powder and binder resin are solvent or dispersed Applying to the support surface as a coating solution dissolved or dispersed in a medium and drying Ri, preferably 0.05 to 20 m, is formed and more preferably at 0.1~10μm thickness.
[0019]
As the laminated structure of the photoreceptor in the present invention, in the case of a single layer type photosensitive layer, for example, a support / photosensitive layer, a support / undercoat layer / photosensitive layer and the like can be mentioned. For example, support / charge generation layer / charge transport layer, support / charge transport layer / charge generation layer, support / undercoat layer / charge generation layer / charge transport layer, support / undercoat layer / charge transport layer / Examples include a charge generation layer.
[0020]
Further, on the surface of the photoreceptor having the above various laminated structures, a surface protective layer mainly composed of the above-described binder resin or the like is preferably 0.01 to 20 μm, more preferably 0.1 to 10 μm. May be provided.
[0021]
In the case of a single layer type, the photosensitive layer is formed on the conductive support of the photosensitive member in the present invention by using the charge generating material, the charge transporting material, and the binder resin or additive as a solvent or As a coating solution dissolved or dispersed in a dispersion medium, in the case of a laminate type, as a coating liquid in which the charge generation material, the binder resin, and the additive are dissolved or dispersed in a solvent or a dispersion medium, and The charge transport material, the binder resin, the additive and the like are dissolved or dispersed in a solvent or a dispersion medium, and dried on the support or an undercoat layer formed on the support, respectively. In the case of a single layer type, the thickness is preferably 5 to 60 μm, more preferably 10 to 45 μm. In the case of a laminated type, the charge generation layer is preferably 0.05 to 5 μm, more preferably 0.1 to 2 μm. The charge transport layer is preferably 10 to 60 [mu] m, further preferably coated to a 15-40 [mu] m, made by drying.
[0022]
Examples of the solvent or dispersion medium used for preparing the coating liquid at that time include alcohols such as methyl alcohol, ethyl alcohol, and propyl alcohol, methyl formate, ethyl acetate, methyl cellosolve, methyl cellosolve acetate, tetrahydrofuran, 1 Ethers such as 1,4-dioxane, esters such as ethyl acetate and butyl acetate, ketones such as acetone, methyl ethyl ketone and cyclohexanone, aromatic hydrocarbons such as benzene, toluene and xylene, chloroform, dichloromethane, 1,2- Chlorinated hydrocarbons such as dichloroethane, 1,1,2-trichloroethane, 1,1,1-trichloroethane, tetrachloroethane, 1,2-dichloropropane, trichloroethylene, n-butylamine, isopropanolamine Nitrogen-containing compounds such as diethylamine, triethanolamine, ethylenediamine, and triethylenediamine, and aprotic polar solvents such as acetonitrile, N-methylpyrrolidone, N, N-dimethylformamide, dimethylsulfoxide, and the like can be mentioned. Alternatively, two or more kinds are used in combination.
[0023]
Examples of the coating method at that time include a dipping method, a spray method, a bar coater method, a blade method, a roll coater method, a wire bar method, and a knife coater method. Using a steam dryer, an infrared dryer, a far-infrared dryer or the like, the temperature is usually 100 to 250 ° C., preferably 110 to 170 ° C.
[0024]
In the present invention, the toner for developing the electrostatic latent image formed on the photosensitive layer of the photoreceptor is formed by coating the surface of toner particles having a basic composition of a colorant and a binder resin with a fine powder.
[0025]
Here, as the colorant in the toner particles, various inorganic and organic dyes and pigments generally used as the colorant of this kind of toner are used. Examples of the inorganic dyes and pigments include carbon black, Lamp black, iron oxide, manganese oxide, copper oxide, chromium oxide, bitumen, ultramarine, etc., and organic dyes such as phthalocyanine, anthraquinone, quinone, monoazo, bisazo, trisazo, Polyazo, triphenylmethane, cyanine, perinone, perylene, quinacridone, polycyclic quinone, pyrylium, thiapyrylium, indigo, thioindigo, anthanthrone, pyranthrone, isoindoline, thiazine , Nigrosine, rhodamine and the like.
[0026]
Further, the colorant may have magnetism, and as the magnetic colorant, a ferromagnetic material exhibiting ferrimagnetism or ferromagnetism at a temperature around 0 to 60 ° C., which is a use environment temperature of a copying machine, and the like. For example, magnetite (Fe ₃ O ₄ ), maghemite (γ-Fe ₂ O ₃ ), an intermediate between magnetite and maghemite, ferrite (M _x Fe _{3 -x} O ₄ ; where M is Mg , Mn, Fe, Co, Ni, Cu, Zn, Cd, etc.), spinel ferrite such as BaO.6Fe ₂ O ₃ , SrO.6Fe ₂ O _3, etc., Y ₃ Fe ₅ O ₁₂ , Sm ₃ Among garnet type oxides such as Fe ₅ O ₁₂ , rutile type oxides such as CrO ₂ , metals such as Cr, Mn, Fe, Co, Ni or their ferromagnetic alloys, etc. Shows ferrimagnetism or ferromagnetism Ones mentioned, in, magnetite, intermediates maghemite or magnetite and maghemite are preferred.
[0027]
Also, the binder resin in the toner particles is not particularly limited, and conventionally known, for example, styrene, butadiene, acrylic acid, methacrylic acid, acrylic ester, methacrylic ester, acrylonitrile, vinyl acetate, vinyl chloride, Homopolymers or copolymers of vinyl compounds such as vinyl alcohol, vinyl butyral, vinyl pyrrolidone, saturated polyester resins, polycarbonate resins, polyamide resins, polyolefin resins, polyarylate resins, polysulfone resins, polyphenylene ether resins, and unsaturated polyesters Examples thereof include resins, phenol resins, epoxy resins, urethane resins, and rosin-modified maleic acid resins.
[0028]
The content ratio of the colorant in the toner particles is preferably 1 to 20 parts by weight, more preferably 2 to 15 parts by weight with respect to 100 parts by weight of the binder resin.
[0029]
The toner particles in the present invention preferably contain a charge control agent. As the charge control agent, conventionally known, for example, nigrosine dyes, quaternary ammonium salt compounds, triphenylmethane compounds Positive charge control agents such as imidazole compounds, polyamine resins, metal-containing azo dyes such as chromium, cobalt, aluminum and iron, metal salts and metals such as chromium, zinc and aluminum of salicylic acid or alkylsalicylic acid Complex, benzylic acid metal salt or metal complex, amide compound, phenol compound, naphthol compound, negative charge control agent such as phenolamide compound, etc., among them, the following general formula (I), (II), (III), (IV), and a compound represented by (V), and a metal salt or metal of a compound represented by the following general formula (I), (III), or (IV) Body, particularly preferred boron complex of the compound represented by the following general formula (IV).
[0030]
[Chemical 1]

[0031]
[In the formula (I), A, B, C and D each independently represent an aromatic ring which may have a substituent, and Q represents a direct bond or a divalent linking group. . ]
[0032]
Here, examples of the aromatic ring of A, B, C, and D in the formula (I) include a benzene ring, a naphthalene ring, an anthracene ring, a phenanthrene ring, and the like. Among them, a benzene ring or a naphthalene ring Are preferred, and a benzene ring is particularly preferred. Examples of the substituent in these aromatic rings include hydrocarbon groups, alkoxy groups, alkylthio groups, dialkylamino groups, nitro groups, cyano groups, hydroxyl groups, halogen atoms, and the like. preferable. Examples of the divalent linking group for Q include an oxygen atom, a sulfur atom, an alkylene group, an alkenylene group, an alkylimino group, and the like. The alkylene group of 4 or the C2-C4 alkenylene group which may have a substituent is preferable. The metal in the metal salt or metal complex of the compound of formula (I) is preferably an alkali metal or alkaline earth metal, and particularly preferably potassium or sodium.
[0033]
[Chemical 2]

[0034]
In [Formula (II), R ¹ and R ² are each independently a hydrocarbon group having 1 to 12 carbon atoms which may have a substituent, a halogen atom, or a hydrogen atom, R ³ and R ⁴ each independently represents an optionally substituted hydrocarbon group having 1 to 5 carbon atoms or a hydrogen atom, n and m are integers of 0 or more, and n + m is 4 to 10. is there. ]
[0035]
Here, as R < ¹ >, R < ² >, R < ³ >, and R < ⁴ > in the formula (II), an optionally substituted alkyl group having 1 to 5 carbon atoms or a hydrogen atom is preferable, and R < ¹ > and R ² is an optionally substituted alkyl group having 3 to 5 carbon atoms, and R ³ and R ⁴ are particularly preferably hydrogen atoms. Further, n + m is preferably 6 to 9, and particularly preferably 8.
[0036]
[Chemical 3]

[0037]
[In Formula (III), R ⁵ and R ⁶ each independently represent a hydrocarbon group having 1 to 12 carbon atoms which may have a substituent, or a hydrogen atom. ]
[0038]
Here, R ⁵ and R ⁶ in the formula (III) are preferably an alkyl group having 3 to 5 carbon atoms which may have a substituent. Further, as the metal in the metal salt or metal complex of the compound of formula (III), a divalent or trivalent metal is preferable, and chromium, aluminum, or zinc is particularly preferable.
[0039]
[Formula 4]

[0040]
[In formula (IV), E and F each independently represent an aromatic ring which may have a substituent. ]
[0041]
Here, examples of the aromatic ring of E and F in the formula (IV) include a benzene ring, a naphthalene ring, an anthracene ring, a phenanthrene ring, and the like. Among them, a benzene ring or an anthracene ring is preferable, and a benzene ring is Particularly preferred. Examples of the substituent in these aromatic rings include a hydrocarbon group, an alkoxy group, an alkylthio group, a dialkylamino group, a nitro group, a cyano group, a hydroxyl group, and a halogen atom. Are preferred. The metal in the metal salt or metal complex of the compound of formula (IV) is preferably a divalent or trivalent metal, particularly preferably chromium, aluminum, or zinc. Also preferred are boron complexes of compounds of formula (IV).
[0042]
[Chemical formula 5]

[0043]
[In the formula (V), R ⁷ , R ⁸ , R ⁹ and R ¹⁰ are each independently a hydrocarbon group having 1 to 5 carbon atoms which may have a substituent, a nitro group, a cyano group, A halogen atom or a hydrogen atom; R ¹¹ and R ¹² each independently represents an N-phenylcarbamoyl group or a hydrogen atom; M represents a trivalent metal; X ⁺ represents a proton or an ammonium ion; Or an alkali metal ion. ]
[0044]
Here, it is preferable that at least one of R ⁷ , R ⁸ , R ⁹ and R ¹⁰ in the formula (V) is a nitro group or a chlorine atom, and M is chromium or iron. X ⁺ is preferably a proton, potassium ion, or sodium ion.
[0045]
The content of the charge control agent in the toner particles is preferably 0.01 to 10 parts by weight, more preferably 0.1 to 5 parts by weight with respect to 100 parts by weight of the binder resin.
[0046]
In the present invention, it is preferable that the toner particles further contain waxes for the purpose of improving the releasability at the time of fixing to the transfer material. , Low molecular weight polyethylene, low molecular weight polypropylene, polyolefin wax such as low molecular weight ethylene-propylene copolymer, paraffin wax, ester wax having a long chain aliphatic group such as stearic acid ester, behenic acid ester, montanic acid ester , Plant waxes such as hydrogenated castor oil, carnauba wax, ketones having long chain alkyl groups such as distearyl ketone, silicones having alkyl groups, higher fatty acids such as stearic acid, long chain aliphatic alcohols, pentaerythritol, etc. (Partial) ester with long chain fatty acid, oleic acid amide, stearin Higher fatty acid amides such as amide. Low molecular weight polytetrafluoroethylene is also useful. In addition, as these waxes in this invention, it is preferable that melting | fusing point is 50-100 degreeC.
[0047]
The content of the wax in the toner particles is preferably 0.1 to 25 parts by weight, more preferably 5 to 15 parts by weight with respect to 100 parts by weight of the binder resin.
[0048]
Further, in the present invention, as the toner particles, various known internal additives such as silicone oil and silicone varnish are used for modifying the adhesiveness, cohesiveness, fluidity, chargeability, surface resistance, etc. of the toner. You may contain.
[0049]
The method for producing toner particles in the present invention is not particularly limited. For example, the colorant, the binder resin powder, the charge control agent, the waxes, etc., for example, a tumbler blender, After uniformly mixing with a blender such as a ribbon blender, V-type blender, Henschel mixer, super mixer, etc., it is melt-kneaded with a kneader such as a uniaxial or biaxial extruder to obtain a resin composition for toner particles, The resin composition is roughly pulverized or further pulverized by, for example, a jaw crusher, a gyrate crusher, a roll mill, a hammer mill, a feather mill, etc., and the average particle size is usually about 50 to 3,000 μm, preferably about 50 to After making coarse particles of about 500 μm, the coarse particles are, for example, roll mill, hammer mill, ball mill Finely pulverize into a powder of about several tens of μm or less with a jet mill or the like, and classify the obtained powder with a classifier such as an inertia class elbow jet, a centrifugal class microplex, or a DS separator. After the toner particles having a specified particle size, a pulverization method in which a spheroidizing means such as a mechanofusion method or a surffusion method is applied as necessary, or the binder resin component monomer, the colorant, and the charge control agent, The suspension polymerization method in which suspension polymerization is performed in the presence of the waxes, and the emulsion obtained by emulsion polymerization of the binder resin component monomer are stirred in the presence of the colorant, the charge control agent, and the waxes. Examples thereof include an emulsion polymerization aggregation method in which emulsion particles are aggregated (aggregated).
[0050]
Among these, in the present invention, an emulsion polymerization aggregation method is preferable. In this case, it is preferable to perform seed polymerization using the wax fine particles as seeds in the emulsion polymerization of the binder resin component monomer.
[0051]
The toner in the present invention is one in which the surface of the toner particles is coated with an inorganic fine powder and an organic fine powder. Examples of the inorganic fine powder include conventionally known, for example, alumina, silica, titania, oxidation Metal oxides and hydroxides such as zinc, zirconium oxide, cerium oxide, talc and hydrotalcite, metal titanates such as calcium titanate, strontium titanate and barium titanate, nitrides such as titanium nitride and silicon nitride , Carbides such as titanium carbide and silicon carbide, and magnetic powders such as ferrite and magnetite, and organic fine powders thereof are conventionally known, for example, styrene resin, acrylic resin, benzoguanamine resin, melamine resin, etc. Resins and, for example, calcium oleate, zinc oleate, calcium stearate, steer Higher fatty acid metal salts such as phosphate zinc, and the like, respectively. Among these, alumina, silica, and titania are preferable as the inorganic fine powder, and styrene resin and acrylic resin are preferable as the organic fine powder.
[0052]
Moreover, the average particle diameter of these fine powders is preferably 0.01 to 1 μm, more preferably 0.01 to 0.5 μm in the case of inorganic fine powders. Moreover, in organic fine powder, it is preferable that it is 0.05-3 micrometers, and it is still more preferable that it is 0.1-1 micrometer. Here, the average particle diameter is obtained as an arithmetic average value of the particle diameters of 500 arbitrary particles measured by a transmission electron microscope. When the average particle diameter is not circular, the area of the projected image by image processing The diameter of the circle was the same as that of the particle size.
[0053]
Further, as the inorganic fine powder, for example, a surface treated with a silane coupling agent, silicone oil or the like is preferable, whereby the degree of water repellency is preferably 50 or more, and more preferably 60 or more. preferable. Here, the degree of water proofing is as follows: 0.20 g of a precisely weighed sample is collected in a beaker, 50 ml of pure water is added, methanol is poured onto the liquid surface while stirring with a magnetic stirrer, and the sample is placed on the liquid surface. It is calculated by the following formula from the amount of methanol injected at the time when no longer observed.
Flooding degree = [methanol injection amount / (50 + methanol injection amount)] × 100
[0054]
In the present invention, the inorganic fine powder species [N _I ] are 2 to 5 types, the organic fine powder species [N 2 _O ] are 1 to 3 types, and the inorganic fine powder types [N _O ] are 100 parts by weight of the inorganic particles. total parts by weight of fine powder [W _I], and the total weight of the powder organic fine powder [W _O], and the arithmetic average particle diameter [D the sum of the average particle size of the powder their inorganic fine powder divided by N _{I I} ], and the arithmetic average particle size [D _O ] obtained by dividing the total average particle size of the organic fine powders by N 2 _O has the relationship of the following formulas (1), (2), and (3): Required.
[0055]
2.0 ≦ W ₁ ≦ 5.0 (1)
0.01 ≦ W ₀ ≦ 2.0 (2)
1.2 ≦ (D ₀ × W ₀ ) / (D ₁ × W ₁ ) ≦ 5 (3)
[0056]
When the total weight part [W _I ] of the inorganic fine powder is less than the above range, and the total weight part [W _O ] of the organic fine powder exceeds the above range, the fluidity as the toner is reduced, When the total weight part [W _I ] of the inorganic fine powder exceeds the above range, filming of the photoconductor occurs, and when the total weight part [W _O ] of the organic fine powder is less than the above range, as a toner In any case, the image quality of the obtained image is degraded. Even if the value of [(D _O × W _O ) / (D _I × W _I )] is outside the above range, it is difficult to obtain a high-quality image.
[0057]
In the present invention, the toner particle surface is coated with the inorganic fine powder and the organic fine powder to form a toner, and the inorganic fine powder and the organic fine powder are added to the toner particles. It is made by stirring and mixing uniformly with a mixer such as a Henschel mixer.
[0058]
The toner of the present invention has a number average particle size [D _n (50% cumulative frequency) of a volume average particle size [D _v (μm)] at a 50% cumulative frequency as a particle size distribution measured using a multisizer manufactured by Coulter. [mu] m)] ratio [D _v / D _n] for the, is preferably from 1.0 to 1.25, even more preferably from 1.0 to 1.20. Further, the proportion of particles having a particle size of 5.0 μm or less is 10% by number or more, the proportion of particles having a particle size of 8.0 to 12.7 μm is 40% by number or less, and the proportion of particles having a particle size of 16.0 μm or more is 2% by number or less. In addition, the volume average particle diameter [D _v ] at a 50% cumulative frequency is particularly preferably 4 to 10 μm.
[0059]
In addition, using a flow type particle image analyzer “FPIA-2100” manufactured by Sysmex Corporation, the circularity at a 50% cumulative frequency of circularity obtained by the following equation is 0.92 to 1.0. And more preferably 0.94 to 1.0.
Circularity = circumference of a circle having the same area as that of the projected particle image / perimeter of the projected particle image
Here, the “circularity at a 50% cumulative frequency of circularity” is a distribution curve having a circularity of 0 to 1 determined by the above equation on the horizontal axis and the cumulative frequency of 0 to 100% on the vertical axis. The degree of circularity in% cumulative frequency.
[0061]
In addition, the storage elastic modulus measured under the condition of a frequency of 1 Hz with a parallel plate using a dynamic viscoelasticity measuring device “MR-500” manufactured by UBM is a value measured at 150 ° C. as a monochromatic toner. Further, as a value measured at 120 ° C. for a full color toner, a storage elastic modulus at 1% strain [G ′ _1% (Pa)] and a storage elastic modulus at 30% strain [G ′ _30% (Pa)]. Are preferably those having the relationship of the following formulas (4) and (5).
[0062]
1.0 × 10 ² ≦ G ′ _1% ≦ 1.0 × 10 ⁴ (4)
1.0 ≦ G ′ _1% / G ′ _30% ≦ 10.0 (5)
[0063]
As the toner in the present invention, a magnetic two-component coexisting magnetic powder such as ferrite, magnetite or the like as a carrier for conveying the toner to the electrostatic latent image portion by magnetic force, or containing these magnetic powder in the toner Either a magnetic one component or a non-magnetic one component that does not use magnetic powder in the toner may be used, but a non-magnetic one component or a magnetic one component is preferable. The magnetic powder as the carrier is preferably one that has been surface-treated with a fluorine resin such as polyvinylidene fluoride or polytetrafluoroethylene.
[0064]
The image forming method of the present invention will be described based on the drawings in the case of using a non-magnetic one-component toner. FIG. 1 is a schematic diagram showing an embodiment of an image forming apparatus used in the image forming method of the present invention. 1 is a photosensitive member, 1a is a conductive support, 1b is a photosensitive layer, 2 is a charging device, 3 is an exposure device, 4 is a developing device, 4a is a developing roller, 4b is a toner supply roller, 4c is a blade, 4d Is an agitator, 5 is a transfer device, 6 is a cleaning device, 7 is a fixing device, 7a is a lower fixing member, 7b is an upper fixing member, 7c is a heating device, T is toner, P is recording paper, charging device 2, The exposure device 3, the developing device 4, the transfer device 5, and the cleaning device 6 are disposed along the outer peripheral surface of the photoreceptor 1.
[0065]
Here, the photoreceptor 1 is made of a conductive metal such as aluminum, and is a drum-shaped support 1a that can be rotated by a rotation drive mechanism (not shown), and a photosensitive layer formed on the outer peripheral surface thereof. 1b. The charging device 2 includes a scorotron charger, a roller charger, and the like disposed in contact with the outer peripheral surface of the photosensitive member 1 and uniformly charges the surface of the photosensitive member 1 to a predetermined potential. The exposure device 3 includes a light source irradiation device such as an LED or a laser beam, and forms an electrostatic latent image on the photosensitive layer 1 b of the photoreceptor 1.
[0066]
The developing device 4 is made of a metal roll such as iron, stainless steel, aluminum, or nickel, or a metal roll whose outer peripheral surface is coated with silicon resin, fluorine resin, urethane resin, or the like. The developing roller 4a is disposed in contact with the outer peripheral surface of the photosensitive member 1 and is made of a conductive sponge. A toner supply roller 4b, which is in contact with the developing roller 4a and is rotatably arranged by a rotation driving mechanism (not shown), carries the toner T stored in the developing device 4 and supplies the toner T to the developing roller 4a; And made of resin such as silicon resin and urethane resin, or made of metal such as stainless steel, aluminum, copper, brass, phosphor bronze, or metal coated with resin on the surface, etc. The blade 4c is disposed by pressing the outer peripheral surface of the roller 4a with a spring or the like, and regulates the layer thickness of the toner T supplied to the outer peripheral surface of the developing roller 4a by the toner supply roller 4b, and a rotation drive mechanism (not shown). And agitator 4d that stirs toner T stored in developing device 4 and has a blade shape that can be rotated by the rotation of the agitator 4d.
[0067]
The transfer device 5 includes a transfer charger, a transfer roller, a transfer belt, and the like that are disposed in contact with the outer peripheral surface of the photosensitive member 1 and is applied with a predetermined voltage having a polarity opposite to the charging potential of the toner T. The toner image formed on the photoreceptor 1 is transferred onto the recording paper P. The cleaning device 6 includes a cleaning member such as a blade or a fur brush, and scrapes off the toner T remaining on the outer peripheral surface of the photoreceptor 1. Further, the fixing device 7 is similar to the lower fixing member 7a formed of a roller in which a metal element tube such as stainless steel or aluminum is coated with silicon resin or fluorine resin, or a sheet in which the metal sheet is coated with resin. And an upper fixing member 7b provided in pressure contact with the lower fixing member 7a. A heating device 7c is provided in any of the members 7a and 7b (upper fixing member 7b in the drawing). The toner T in the toner image on the recording paper P is heated to a molten state and fixed on the recording paper P.
[0068]
In the image forming method of the present invention, the surface of the photosensitive member 1 on which the photosensitive layer 1b containing the Y-type oxytitanium phthalocyanine as a charge generating agent is formed on the conductive support 1a is charged with a predetermined potential by the charging device 2. Then, it is exposed to light by the exposure device 3 to dissipate the charge of the exposed portion, thereby forming an electrostatic latent image on the photosensitive layer 1b. The electrostatic latent image is visualized and developed by attaching the charged toner T carried on the developing roller 4a, and the obtained toner image is transferred to the recording paper P by the transfer device 5, and the transferred recording is performed. The toner T on the paper P is heated and pressurized by the fixing device 7 to be fixed on the recording paper P. The outer peripheral surface of the photosensitive member 1 is cleaned by the cleaning device 6 and the same operation as described above is repeated.
[0069]
The image forming method of the present invention has a high image density and can form a high-quality image. Especially in a small and high-speed image forming apparatus, and since the sensitivity in the wavelength region of 750 to 850 nm is high, It is preferably used in an image forming apparatus using a semiconductor laser as an exposure light source.
[0070]
【Example】
EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples unless it exceeds the gist. In addition, each manufacture example of the photoreceptor and toner particle used in the following Examples and Comparative Examples, and inorganic fine powder and organic fine powder are shown below.
[0071]
<Photoconductor Production Example 1>
On a cylindrical aluminum support having a diameter of 30 mm, as a charge generating material, Bragg angles (2θ ± 0.2 °) of 27.3 °, 24.2 °, 9.7 °, and X-ray diffraction spectrum by CuKα ray A coating solution containing 200 parts by weight of Y-type oxytitanium phthalocyanine having a diffraction peak at 7.4 ° and 100 parts by weight of polyvinyl butyral (“Denka Butyral # 6000C” manufactured by Denki Kagaku Kogyo Co., Ltd.) as a binder resin is applied and dried. To form a charge generation layer having a thickness of 0.4 μm, on which 70 parts by weight of N-methyl-3-carbazolecarbaldehyde diphenylhydrazone is used as a charge transport material, and a polycarbonate resin (Mitsubishi Chemical Corporation) is used as a binder resin. "Novalex 8025A") 100 parts by weight and p-nitrobenzoyloxybenzal Rononitoriru 2 parts by weight of coating liquid was applied containing, by drying to form a charge transport layer having a thickness of 15μm and was prepared a photosensitive member having a photosensitive layer of the multilayer.
[0072]
<Photoconductor Production Example 2>
As a charge generation material, diffracted into Bragg angles (2θ ± 0.2 °) of 22.3 °, 17.3 °, 16.7 °, 9.1 °, and 7.5 ° in an X-ray diffraction spectrum by CuKα ray A photoconductor was produced in the same manner as in Production Example 1 except that X-type metal-free phthalocyanine having a peak was used.
[0073]
<Production Example 1 of Toner Particles>
As a coloring agent, 10 parts by weight of a master pigment of 40% by weight of a cyan pigment (Pigment Blue 15: 3), 100 parts by weight of a saturated polyester resin as a binder resin, and benzylic acid which is a compound of the above general formula (IV) as a charge control agent 1 part by weight of a boron complex (“LR-147” manufactured by Nippon Carlit Co., Ltd.) and 5 parts by weight of paraffin wax having a melting point of 80 ° C. are mixed with a Henschel mixer and then melt-kneaded using a twin screw extruder. A resin composition is prepared, cooled, coarsely pulverized with a hammer mill, then finely pulverized with a supersonic jet mill, and the resulting powder is classified with an air classifier, and further spheronized by a surffusion method. To produce toner particles.
[0074]
<Toner Particle Production Example 2>
Toner particles were produced in the same manner as in Toner Particle Production Example 1 except that no paraffin wax was used and no spheronization treatment was performed by the surffusion method.
[0075]
<Production Example 3 of Toner Particles>
An ester wax containing tetrastearic acid ester of pentaerythritol (“Yunistar H4760” manufactured by NOF Corporation) as well as 1.67 parts by weight of sodium dodecylbenzenesulfonate and 68.33 parts by weight of demineralized water By emulsifying under high-pressure shear, an emulsion of ester wax fine particles having an average particle size of 0.26 μm was prepared, and then the ester wax emulsion obtained above was charged into a reactor having an internal volume of 3 liters 53.1 wt. And 406 parts by weight of demineralized water were added and the temperature was raised to 90 ° C. under a nitrogen stream, and then 1.6 parts by weight of an 8% aqueous hydrogen peroxide solution and 1.6 parts by weight of an 8% ascorbic acid aqueous solution were added. , 80 parts by weight of styrene, 20 parts by weight of butyl acrylate, 1 part by weight of acrylic acid, hexanediol diacryl 0.8 parts by weight, a mixture of 0.45 parts by weight of trichlorobromomethane as a chain transfer agent and 0.01 parts by weight of 2-mercaptoethanol, and 1 part by weight of a 10% by weight aqueous sodium dodecylbenzenesulfonate solution An aqueous emulsifier solution with 25 parts by weight of brine is added over 5 hours, and 9 parts by weight of an 8% aqueous hydrogen peroxide solution and 9 parts by weight of an 8% ascorbic acid aqueous solution are added over 6 hours. The emulsion was copolymerized and cooled to obtain a primary particle emulsion of a copolymer mainly composed of styrene-butyl acrylate-acrylic acid, and then the polymer primary obtained as described above was placed in a reactor having an internal volume of 1 liter. 100 parts by weight of particle emulsion as solids and 0.5 weight of 10% by weight aqueous sodium dodecylbenzenesulfonate solution Then, 6.7 parts by weight of 35% by weight aqueous dispersion of a cyan pigment (pigment blue 15: 3) as a colorant is added as a solid, and mixed uniformly. Then, 0.6 parts by weight of aluminum sulfate as an aqueous solution was dropped, and the temperature was raised to 50 ° C. over 20 minutes with stirring and held for 1 hour, and further heated to 53 ° C. over 6 minutes. When the diameter reached 7.1 μm, 0.07 part by weight of aluminum sulfate was added dropwise as an aqueous solution, the temperature was raised to 55 ° C. over 10 minutes with stirring, and held for 30 minutes. Further, 10% by weight 3 parts by weight of sodium dodecylbenzenesulfonate aqueous solution was added, the temperature was raised to 95 ° C. over 35 minutes with stirring, and maintained for 3.5 hours, followed by cooling, filtration, washing with water, and drying. Toner particles were produced.
[0076]
<Inorganic fine powder>
(1) Silica having an average particle size of 0.04 μm and a degree of water repellency of 70.
(2) Silica having an average particle size of 0.015 μm and a hydrophobization degree of 60.
(3) Silica having an average particle size of 0.012 μm and a degree of flooding of 70.
(4) Titania having an average particle size of 0.015 μm and a degree of flooding of 70.
<Organic fine powder>
(1) Acrylic resin beads having an average particle size of 0.3 μm.
(2) Styrene resin beads having an average particle size of 0.2 μm.
[0077]
Examples 1-3
The inorganic fine powder and the organic fine powder shown in the following Table 1 were added to 100 parts by weight of the toner particles of Production Example 1, and each toner was produced by stirring and mixing with a Henschel mixer.
[0078]
The obtained toner has a ratio [D _v / D _n ] of the volume average particle diameter [D _v ] to the number average particle diameter [D _n ] as a particle size distribution measured using a multisizer manufactured by Coulter Co. The ratio of particles having a particle diameter of 5.0 μm or less is 12.2% by number, the ratio of particles having 8.0 to 12.7 μm is 9.9% by number, and the ratio of particles having a particle diameter of 16.0 μm or more is 16. 0.3% by number, the volume average particle size [D _v ] is 7.9 μm, and the circularity measured using a flow type particle image analyzer “FPIA-2100” manufactured by Sysmex Corporation is 0.93. Yes, using a dynamic viscoelasticity measuring device “MR-500” manufactured by UBM, measured at 120 ° C. under conditions of a frequency of 1 Hz on a parallel plate, storage elastic modulus at 1% strain [G ′ _{1 %]} is 5.8 × 10 storage modulus at ³ Pa, 30% strain [G _'30%] 2.9 10 ³ Pa, were those _{G '1% / G' 30} % is 2.0.
[0079]
Subsequently, using the image forming apparatus shown in FIG. 1, image formation in which the electrostatic latent image formed on the photosensitive layer of the photoreceptor of Production Example 1 is developed with each of the toners described above is performed at a temperature of 25 ° C. and a relative humidity. Regarding the image characteristics such as the image density, resolution, and gradation of the image on each recording sheet obtained in the initial stage and after 5,000 sheets are actually taken, the image quality “ “Good” and “bad” were determined, and the results were evaluated according to the following criteria. The results are shown in Table 1 below.
[0080]
◎: 10 people judged to be good.
○: Nine people judged to be good.
Δ: 5 to 8 people judged to be good.
×: Number of people judged to be good is 4 or less.
[0081]
Example 4
Using the toner produced by adding the inorganic fine powder and the organic fine powder shown in the following Table 1 to 100 parts by weight of the toner particles of Production Example 3 and stirring and mixing with a Henschel mixer, in the same manner as in Example 1. An image was formed and its image characteristics were evaluated. The results are shown in Table 1 below.
[0082]
The obtained toner has a ratio [D _v / D _n ] of volume average particle diameter [D _v ] to number average particle diameter [D _n ] as a particle size distribution measured using a multisizer manufactured by Coulter, Inc. The ratio of particles having a particle diameter of 5.0 μm or less is 12.0% by number, the ratio of particles having a particle size of 8.0 to 12.7 μm is 16.1% by number, and particles having a particle diameter of 16.0 μm or more. The ratio is 0.3% by number, the volume average particle size [D _v ] is 7.5 μm, and the circularity measured by using a flow type particle image analyzer “FPIA-2100” manufactured by Sysmex Corporation is 0.00. The storage elastic modulus at 1% strain [G] was measured using a dynamic viscoelasticity measuring device “MR-500” manufactured by UBM Co., Ltd. at 120 ° C. under a condition of a frequency of 1 Hz. _'1%] is the storage elastic modulus at 4.3 × 10 ³ Pa, 30% strain [G' _30%] ^{.9 × 10 3 Pa, G '} 1% / G' 30% were of 2.3.
[0083]
Comparative Example 1
Using the toner manufactured by adding the inorganic fine powder and the organic fine powder shown in the following Table 1 to 100 parts by weight of the toner particles of Preparation Example 2 and stirring and mixing with a Henschel mixer, in the same manner as in Example 1. Images were formed and the image characteristics were evaluated. The results are shown in Table 1 below.
[0084]
The obtained toner has a ratio [D _v / D _n ] of volume average particle diameter [D _v ] to number average particle diameter [D _n ] as a particle size distribution measured using a multisizer manufactured by Coulter, Inc. The ratio of particles having a particle diameter of 5.0 μm or less is 9.8% by number, the ratio of particles having a particle size of 8.0 to 12.7 μm is 20.8% by number, and particles having a particle diameter of 16.0 μm or more. The ratio is 3.3% by number, the volume average particle size [D _v ] is 7.8 μm, and the circularity measured by using a flow type particle image analyzer “FPIA-2100” manufactured by Sysmex Corporation is 0.00. The storage elastic modulus at 1% strain [G] was measured at 120 ° C. under the condition of a frequency of 1 Hz using a dynamic viscoelasticity measuring device “MR-500” manufactured by UBM. _'1%] is 11.8 × 10 storage modulus at ³ Pa, 30% strain [G' _30%] ^{.0 × 10 3 Pa, G '} 1% / G' 30% were of 1.7.
[0085]
[Table 1]

[0086]
【The invention's effect】
According to the present invention, when an electrostatic latent image formed on a photosensitive layer of a photoreceptor is developed with toner to form an image, a high-quality image can be formed with a high image density. An image forming method suitably used in a high-speed image forming apparatus can be provided.
[Brief description of the drawings]
FIG. 1 is a schematic view showing an embodiment of an image forming apparatus used in an image forming method of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1; Photosensitive body 1a; Conductive support 1b; Photosensitive layer 2; Charging device 3; Exposure device 4; Developing device 4a; Developing roller 4b: Toner supply roller 4c; Blade 4d; Fixing device 7a; lower fixing member 7b; upper fixing member 7c; heating device T; toner P; recording paper

Claims (5)

In an image forming method in which an electrostatic latent image formed on a photosensitive layer of a photoreceptor is developed with toner, the photosensitive layer serves as a charge generating agent and has a Bragg angle (2θ ± 0.2 °) of 27.3 in an X-ray analysis spectrum. The toner contains oxytitanium phthalocyanine having the maximum diffraction peak at °, and the toner particle surface is coated with an inorganic fine particle powder and an organic fine particle powder. The inorganic fine powder species [N ₁ ] is 2 to 5 1 to 3 kinds of seeds and organic fine powder seeds [N ₀ ], and the total weight [W ₁ ] of those inorganic fine powders relative to 100 parts by weight of toner particles, and the total weight parts [W ₀ ] of organic fine powders And the arithmetic average particle diameter [D ₁ ] obtained by dividing the sum of the average particle diameters of the inorganic fine particles by N ₁ and the arithmetic average particle obtained by dividing the sum of the average particle diameters of the organic fine powders by N _0. Diameter [ _0], the image forming method characterized by wherein the following formula (1), (2), and (3).
2.0 ≦ W ₁ ≦ 5.0 (1)
0.01 ≦ W ₀ ≦ 2.0 (2)
1.2 ≦ (D ₀ × W ₀ ) / (D ₁ × W ₁ ) ≦ 5 (3)   The image forming method according to claim 1, wherein the toner particles are composed of primary particle aggregates obtained by stirring and mixing polymer primary particles as a binder resin component in the presence of at least a colorant.   The image forming method according to claim 1, wherein the toner particles contain a wax having a melting point of 50 to 100 ° C. The image forming method according to claim 1, wherein the toner has a circularity of 0.92 to 1.0 at a 50% cumulative frequency of the circularity obtained by the following formula.
Circularity = circumference of the circle with the same area as the projected image area / circumference of the projected particle image The toner has a storage modulus [G ′ _1% (Pa)] at ₁ % strain and a storage modulus [G ′ _30% (Pa)] at 30% strain in dynamic viscoelasticity measurement at 120 ° C. The image forming method according to claim 1, wherein the image forming method has a relationship represented by the following formulas (4) and (5).
1.0 × 10 ² ≦ G ′ _1% ≦ 1.0 × 10 ⁴ (4)
1.0 ≦ G ′ _1% / G ′ _30% ≦ 10.0 (5)

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