JP4416343B2 - Toner production method - Google Patents

Description

（式中、ａ及びｂは０〜４迄の整数であり、ａ＋ｂは４である。Ｒ₁及びＲ₂は炭素数が１〜４０の有機基であり、Ｒ₁とＲ₂との炭素数差が３以上である。ｍ及びｎは０〜２５の整数であり、ｍとｎは同時に０になることはない。）
【００３３】
【化２】

（式中、ａ及びｂは０〜３の整数であり、ａ＋ｂは１〜３である。Ｒ₁及びＲ₂は炭素数が１〜４０の有機基であり、Ｒ₁とＲ₂との炭素数差が３以上である。Ｒ₃は水素原子、炭素数が１以上の有機基である。但し、ａ＋ｂ＝２のとき、Ｒ₃のどちらか一方は、炭素数が１以上の有機基である。ｋは１〜３の整数である。ｍ及びｎは０〜２５の整数であり、ｍとｎが同時に０になることはない。）
【００３４】
【化３】

（式中、Ｒ₁及びＲ₃は炭素数６〜３２を有する有機基であり、Ｒ₁とＲ₃は同じものであってもなくても良い。Ｒ₂は炭素数１〜２０を有する有機基を示す。）
【００３５】
【化４】

（式中、Ｒ₁及びＲ₂は炭素数６〜３２を有する有機基であり、Ｒ₁とＲ₃は同じものであってもなくてもよい。
Ｒ₂は−ＣＨ₂ＣＨ₂ＯＣ₆Ｈ₄ＯＣＨ₂ＣＨ₂−、

【００３６】
【化５】

（式中、ａは０〜４の整数であり、ｂは１〜４の整数であり、ａ＋ｂは４である。Ｒ₁は炭素数が１〜４０の有機基である。ｍ及びｎは０〜２５の整数であり、ｍとｎが同時に０になることはない。）
【００３７】
【化６】

（式中、Ｒ₁及びＲ₂は同一又は異なる炭素数１５〜４５の炭化水素基を示す。）
【００３８】
エステル系ワックスの融点としては４０〜１００℃が好ましい。融点が４０℃未満ではトナーの耐ブロッキング性及び保形性が不十分であり、１００℃を超えると離型効果が不十分となる。エステル化合物からなる離型剤としてのエステルワックスとして以下のものが例示される。
【００３９】
【化７】

【００４０】
【化８】

【００４１】
該離型剤が、上記構造式を有するエステル化合物を有するエステルワックスの場合、良好な透明性を発現するとともに、トナー粒子中に含有せしめた場合には良好な定着性を示すものである。
【００４２】
また、離型剤は、本発明においては、重合性単量体１００質量部に対して５乃至４０質量部（より好ましくは１０〜３０質量部）配合し、結果として、重合性単量体から生成された結着樹脂１００質量部当り離型剤５乃至４０質量部（より好ましくは１０〜３０質量部）トナー粒子に含有されるのが良い。
【００４３】
本発明のトナーは荷電制御剤を含有してもよい。
【００４４】
荷電制御剤としては、公知のものが利用できるが、例えばトナーを負荷電性に制御するものとしては、有機金属化合物、キレート化合物が有効であり、モノアゾ金属化合物、アセチルアセトン金属化合物、芳香族ハイドロキシカルボン酸、芳香族ダイカルボン酸系の金属化合物がある。他には、芳香族ハイドロキシカルボン酸、芳香族モノ及びポリカルボン酸及びその金属塩、無水物、エステル類、ビスフェノール等のフェノール誘導体類などがある。
【００４５】
また、尿素誘導体、含金属サリチル酸系化合物、４級アンモニウム塩、カリックスアレーン、ケイ素化合物、スチレン−アクリル酸共重合体、スチレン−メタクリル酸共重合体、スチレン−アクリルスルホン酸共重合体、ノンメタルカルボン酸系化合物等が挙げられる。
【００４６】
トナーを正荷電性に制御するものとしては、ニグロシン及び脂肪酸金属塩等による変性物、トリブチルベンジルアンモニウム−１−ヒドロキシ−４−ナフトスルフォン酸塩、テトラブチルアンモニウムテトラフルオロボレートなどの４級アンモニウム塩、及びこれらの類似体であるホスホニウム塩等のオニウム塩及びこれらのレーキ顔料、トリフェニルメタン染料及びこれらのレーキ顔料（レーキ化剤としては、りんタングステン酸、りんモリブデン酸、りんタングステンモリブデン酸、タンニン酸、ラウリン酸、没食子酸、フェリシアン化物、フェロシアン化物など）、高級脂肪酸の金属塩；ジブチルスズオキサイド、ジオクチルスズオキサイド、ジシクロヘキシルスズオキサイドなどのシオルガノスズオキサイド；ジブチルスズボレート、ジオクチルスズボレート、ジシクロヘキシルスズボレートなどのシオルガノスズボレート類；これらを単独で或は２種類以上組合せて用いることができる。これらの中でも、ニグロシン系、４級アンモニウム塩の如き荷電制御剤が特に好ましく用いられる。
【００４７】
これらの荷電制御剤は、重合性単量体１００質量部に対して、０．０１〜２０質量部（より好ましくは０．５〜１０質量部）使用するのが良い。
【００４８】
カラートナーの場合は、特に、無色でトナーの帯電スピードが速く且つ一定の帯電量を安定して維持できる荷電制御剤が好ましい。更に、重合法により得られるトナーの場合には、重合阻害性が無く水系への可溶化物の無い荷電制御剤が特に好ましい。
【００４９】
重合性単量体を重合せしめる際に適当な重合開始剤を用いることもできる。例えば、２，２’−アゾビス−（２，４−ジメチルバレロニトリル）、２，２’−アゾビスイソブチロニトリル、１，１’−アゾビス（シクロヘキサン−１−カルボニトリル）、２，２’−アゾビス−４−メトキシ−２，４−ジメチルバレロニトリル、アゾビスイソブチロニトリル等のアゾ系重合開始剤；ベンゾイルペルオキシド、メチルエチルケトンペルオキシド、ｔ−ブチルペルオキシ−２−エチルヘキサノエート、ジイソプロピルペルオキシカーボネート、クメンヒドロペルオキシド、２，４−ジクロロベンゾイルペルオキシド、ラウロイルペルオキシド等の過酸化物系重合開始剤が用いられる。該重合開始剤の添加量は目的とする重合度により変化するが、一般的には重合性単量体１００質量部に対し０．５〜２０質量部添加され用いられる。開始剤の種類は重合方法により若干異なるが、十時間半減期温度を参考に単独又は混合し利用される。
【００５０】
本発明における重合性単量体組成物中には架橋剤を含有させることもできる。架橋剤としては、例えば、ジビニルベンゼン、４，４’−ジビニルビフェニル、エチレングリコールジ（メタ）アクリレート、グリシジル（メタ）アクリレート、トリメチロールプロパントリ（メタ）アクリレート等の多官能性化合物を挙げることができる。
【００５１】
また、重合性単量体組成物を水性媒体中に良好に分散させるための分散安定剤として、例えば無機系酸化物であるリン酸三カルシウム、リン酸マグネシウム、リン酸アルミニウム、リン酸亜鉛、炭酸カルシウム、炭酸マグネシウム、水酸化カルシウム、水酸化マグネシウム、水酸化アルミニウム、メタケイ酸カルシウム、硫酸カルシウム、硫酸バリウム、ベントナイト、シリカ、アルミナ、磁性体、フェライト等が挙げられる。有機系化合物としては例えばポリビニルアルコール、ゼラチン、メチルセルロース、メチルヒドロキシプロピルセルロース、エチルセルロース、カルボキシメチルセルロースのナトリウム塩、デンプン等が水相に分散させて使用される。これら分散安定剤は、重合性単量体１００質量部に対して０．２〜１０．０質量部を使用することが好ましい。
【００５２】
これら分散安定剤は、市販のものをそのまま用いても良いが、細かい均一な粒度を有す分散粒子を得るために、分散媒中にて高速撹拌下にて該無機化合物を生成させることもできる。例えばリン酸三カルシウムの場合、高速撹拌下において、リン酸ナトリウム水溶液と塩化カルシウム水溶液を混合することで懸濁重合方法に好ましい分散剤を得ることができる。また、これら分散剤の微細化のため水性媒体１００質量部に対して０．００１〜０．１質量部の界面活性剤を併用しても良い。具体的には市販のノニオン、アニオン、カチオン型の界面活性剤が利用でき、例えばドデシル硫酸ナトリウム、テトラデシル硫酸ナトリウム、ペンタデシル硫酸ナトリウム、オクチル硫酸ナトリウム、オレイン酸ナトリウム、ラウリル酸ナトリウム、ステアリン酸カリウム、オレイン酸カルシウム等が好ましく用いられる。
【００５３】
懸濁重合のように水性分散媒を用いる重合法の場合には、該重合性単量体組成物に極性樹脂を添加することにより、離型剤の内包化の促進を図ることができる。水性分散媒中に分散された重合性単量体組成物中に極性樹脂が存在した場合、親水性の違いから極性樹脂が水性分散媒と重合性単量体組成物の界面付近に移行するため、トナー表面に極性樹脂が偏在する。その結果トナー粒子はカプセル構造を有し、多量の離型剤を含有する場合でも離型剤の内包性が良好になる。
【００５４】
該極性樹脂としては、トナー表面に偏在した際に極性樹脂自身の流動性が期待できることから、特にポリエステル系樹脂が好ましい。
【００５５】
本発明のトナーに用いることができる極性樹脂としては、テレフタル酸、イソフタル酸、フタル酸、フマル酸、マレイン酸、マロン酸、コハク酸、グルタル酸、アジピン酸、ピメリン酸、スベリン酸、アゼライン酸、セバシン酸、しょうのう酸、シクロヘキサンジカルボン酸、トリメリット酸の如き酸成分単量体と；エチレングリコール、ジエチレングリコール、トリエチレングリコール、１，２−プロピレングリコール、１，３−プロピレングリコール、１，４−ブタンジオール、ネオペンチルグリコール、１，４−ビス（ヒドロキシメチル）シクロヘキサン等のアルキレングリコール類及びポリアルキレングリコール類、ビスフェノールＡ、水素添加ビスフェノール、ビスフェノールＡのエチレンオキサイド付加物、ビスフェノールＡのプロピレンオキサイド付加物、グリセリン、トリメチロールプロパン、ペンタエリスリトールの如き多価アルコール単量体とを縮合重合したものを挙げることができる。
【００５６】
本発明により製造されるトナーを使用するにあたっては、各種特性付与を目的として外添剤を使用することができる。外添剤としてはトナーに添加した時の耐久性の点から、トナー粒子の体積平均径の１／１０以下の粒径であることが好ましい。この添加剤の粒径とは電子顕微鏡におけるトナー粒子の表面観察により求めたその平均粒径を意味する。外添剤としては、たとえば、以下のようなものが用いられる。
【００５７】
金属酸化物（酸化アルミニウム，酸化チタン，チタン酸ストロンチウム，酸化セリウム，酸化マグネシウム，酸化クロム，酸化錫，酸化亜鉛など）、窒化物（窒化ケイ素など）、炭化物（炭化ケイ素など）、金属塩（硫酸カルシウム，硫酸バリウム，炭酸カルシウムなど）、脂肪酸金属塩（ステアリン酸亜鉛，ステアリン酸カルシウムなど）、カーボンブラック、シリカなど。
【００５８】
これら外添剤はトナー粒子１００質量部に対し０．０１〜１０質量部が用いられ、好ましくは０．０５〜５質量部が用いられる。これら外添剤は単独で用いても、また複数併用しても良い。それぞれ疎水化処理を行ったものがより好ましい。
【００５９】
さらに本発明のトナーは、磁性材料を含有させ磁性トナーとしても使用しうる。この場合、磁性材料は着色剤の役割をかねることもできる。本発明において、磁性トナー中に含まれる磁性材料としては、マグネタイト、ヘマタイト、フェライト等の酸化鉄；鉄、コバルト、ニッケルのような金属或はこれらの金属のアルミニウム、コバルト、銅、鉛、マグネシウム、スズ、亜鉛、アンチモン、ベリリウム、ビスマス、カドミウム、カルシウム、マンガン、セレン、チタン、タングステン、バナジウムのような金属の合金及びその混合物等が挙げられる。
【００６０】
これらの強磁性体は平均粒子が２μｍ以下、好ましくは０．１〜０．５μｍ程度のものが好ましい。トナー中に含有させる量としては重合性単量体１００質量部に対し約２０〜２００質量部、特に好ましくは重合性単量体１００質量部に対し４０〜１５０質量部が良い。
【００６１】
また、８００ｋＡ／ｍ印加での磁気特性が保磁力（Ｈｃ）１．６〜２４ｋＡ／ｍ、飽和磁化（σｓ）５０〜２００Ａｍ²／ｋｇ、残留磁化（σｒ）２〜２０Ａｍ²／ｋｇのものが好ましい。
【００６２】
本発明により製造されるトナーは、通常一成分及び二成分系現像剤として、いずれの現像剤にも使用できる。たとえば、一成分系現像剤として、磁性体をトナー中に含有せしめた磁性トナーの場合には、現像スリーブ中に内蔵せしめたマグネットを利用し、磁性トナーを搬送及び帯電せしめる方法がある。また、磁性体を含有しない非磁性トナーを用いる場合には、ブレード及びファーブラシを用い、現像スリーブにて強制的に摩擦帯電しスリーブ上にトナーを付着させることで搬送せしめる方法がある。
【００６３】
一方、一般的に利用されている二成分系現像剤として用いる場合には、本発明のトナーと共に、キャリアを用い現像剤として使用する。本発明に使用されるキャリアとしては特に限定されるものではないが、主として、鉄、銅、亜鉛、ニッケル、コバルト、マンガン、クロム元素からなる単独及び複合フェライト状態で構成される。飽和磁化、電気抵抗を広範囲にコントロールできる点からキャリア形状も重要であり、たとえば球状、扁平、不定形などを選択し、更にキャリア表面状態の微細構造、たとえば表面凸凹性をもコントロールすることが好ましい。一般的には、上記無機酸化物を焼成・造粒することにより、あらかじめ、キャリアコア粒子を生成した後、樹脂にコーティングする方法が用いられているが、キャリアのトナーへの負荷を軽減する意味合いから、無機酸化物と樹脂を混練後、粉砕／分級して低密度分散キャリアを得る方法や、さらには、直接無機酸化物とモノマーとの混練物を水系媒体中にて懸濁重合せしめ真球状分散キャリアを得る重合キャリアを得る方法なども利用することが可能である。
【００６４】
上記キャリアの表面を樹脂等で被覆する系は特に好ましい。その方法としては、樹脂等の被覆材を溶剤中に溶解もしくは懸濁せしめて塗布しキャリアに付着せしめる方法、単に粉体で混合する方法等、従来公知の方法がいずれも適用できる。
【００６５】
キャリア表面への固着物質としてはトナー材料により異なるが、例えばポリテトラフルオロエチレン、モノクロロトリフルオロエチレン重合体、ポリフッ化ビニリデン、シリコーン樹脂、ポリエステル樹脂、ジターシャーリーブチルサリチル酸の金属化合物、スチレン系樹脂、アクリル系樹脂、ポリアミド、ポリビニルブチラール、ニグロシン、アミノアクリレート樹脂、塩基性染料及びそのレーキ、シリカ微粉末、アルミナ微粉末などを単独或は複数で用いるのが適当であるが必ずしもこれに制約されない。
【００６６】
上記化合物の処理量は、一般には総量でキャリア１００質量部に対し０．１〜３０質量部、好ましくは０．５〜２０質量部である。
【００６７】
これらキャリアの平均粒径は１０〜１００μｍ、好ましくは２０〜５０μｍを有することが好ましい。
【００６８】
該キャリアの特に好ましい様態としては、Ｃｕ−Ｚｎ−Ｆｅの３元系のフェライトであり、その表面をフッ素系樹脂とスチレン系樹脂の如き樹脂の組み合せ、例えばポリフッ化ビニリデンとスチレン−メチルメタクリレート樹脂；ポリテトラフルオロエチレンとスチレン−メチルメタクリレート樹脂、フッ素系共重合体とスチレン系共重合体；などを９０：１０〜２０：８０、好ましくは７０：３０〜３０：７０の比率の混合物としたもので、０．０１〜５質量％、好ましくは０．１〜１質量％コーティングし、２５０メッシュパス、４００メッシュオンのキャリア粒子が７０質量％以上ある上記平均粒径を有するコートフェライトキャリアであるものが挙げられる。該フッ素系共重合体としてはフッ化ビニリデン−テトラフルオロエチレン共重合体（１０：９０〜９０：１０）が例示され、スチレン系共重合体としてはスチレン−アクリル酸２−エチルヘキシル（２０：８０〜８０：２０）、スチレン−アクリル酸２−エチルヘキシル−メタクリル酸メチル（２０〜６０：５〜３０：１０〜５０）が例示される。
【００６９】
上記コートフェライトキャリアは粒径分布がシャープであり、本発明のトナーに対し好ましい摩擦帯電性が得られ、さらに電子写真特性を向上させる効果がある。
【００７０】
本発明におけるトナーと混合して二成分現像剤を調製する場合、その混合比率は現像剤中のトナー濃度として、２質量％〜１５質量％、好ましくは４質量％〜１３質量％にすると通常良好な結果が得られる。トナー濃度が２質量％未満では画像濃度が低く実用不可となり、１５質量％を超えるとカブリや機内飛散を増加せしめ、現像剤の耐用寿命を短かくする。さらに、該キャリアの磁性特性は以下のものが良い。磁気的に飽和させた後の８０ｋＡ／ｍにおける磁化の強さは３０乃至３００Ａｍ²／ｋｇであることが必要である。さらに高画質化を達成するために、好ましくは１００乃至２５０Ａｍ²／ｋｇであることがよい。３００Ａｍ²／ｋｇより大きい場合には、高画質なトナー画像が得られにくくなる。３０Ａｍ²／ｋｇ未満であると、磁気的な拘束力も減少するためにキャリア付着を生じやすい。
【００７１】
本発明に係る製造方法において、重合／蒸留装置を構成する部材のうち、重合／蒸留容器内の気相部に露出した部分を有するものとしては、容器内壁、撹拌機軸、邪魔板、原料投入口などのノズル類、各種センサー及びその保護管などが挙げられる。これら各部材の材質としては、ステンレス鋼、ガラス、ＦＲＰなど通常使用されるものを用いることができる。また、これらの表面は電解研磨、テフロンコーティング、グラスライニングなどの処理が施されていてもよい。
【００７２】
スプレーノズルには、種々の噴霧パターンのものがあるが、本発明にはフルコーンスプレー、ホローコーンスプレー、フラットスプレーなどの一般的なものを用いることができる。図１はフルコーンスプレーの噴霧パターンを示し、スプレー軸に垂直な面に対して円形のパターンを作る。図２はホローコーンスプレーについて示し、噴霧パターンは円環状である。図３にフラットスプレーの噴霧パターンを示し、噴霧パターンは凸レンズ断面のごとき形状となる。
【００７３】
スプレーは装置の構成により、適したものが選択され、目的物の大きさ、形状に合わせ複数組み合わせることもできる。例えば器壁にはスプレー面積の広いフルコーンスプレーまたはホローコーンスプレー、あるいは円周上に複数個配置されたフラットスプレー、撹拌機軸および邪魔板等にはフラットスプレーが好適に用いられる。
【００７４】
スプレー圧力および流量の関係は、スプレーの種類により大きく異なるが、該スプレーノズルの目的表面への単位面積当たりのスプレー衝撃力が、２．０〜１．１×１０³Ｐａの範囲内であることが望ましく、スプレー圧力および流量はこの範囲内のスプレー衝撃力を達成できるよう調節される。スプレー衝撃力が２．０Ｐａより小さい場合にはスケール状付着物に対する洗浄力が十分ではなく、１．１×１０³Ｐａより大きい場合にはスプレーの勢いが強すぎるため、懸濁液や泡沫の飛散が起こり、かえってスケール付着領域の拡大を招くことになり好ましくない。また、スプレーの種類により、上記範囲内からより好適な範囲を選択することができる。例えば、フルコーンスプレーでは２．０〜１５．７Ｐａ、ホローコーンスプレーでは１．０×１０²〜７．６×１０²Ｐａ、フラットスプレーでは１．０×１０²〜１．１×１０³Ｐａの範囲を選択することが好ましい。
【００７５】
スプレー角度はスプレーの種類、目的物の大きさおよび形状によって適宜選択されるが、１５°〜１２０°の範囲で設定することが好ましい。スプレー角度が１５°より小さい場合は、水または温水の散布される範囲が小さすぎ、必要な面積をカバーするためにスプレーを多数個設置する必要が生じ好ましくない。また、スプレー角度が１２０°より大きい場合には、スプレー衝撃力が極端に小さくなり洗浄力が不十分となるので、やはり好ましくない。
【００７６】
水または温水は重合操作および蒸留操作の行われている間中、散布され続けていることが望ましいが、装置容積や操作条件などの都合から液量の増加を大きくしたくない場合には、適当な頻度で間歇的に散布してもよい。
【００７７】
散布される水または温水の温度は、操作条件により適宜選択されるが、重合時には３０℃〜９０℃の範囲に設定することが好ましい。水温が３０℃より低い場合には懸濁液温の低下を招き、９０℃より高い場合には目的表面の温度が上昇し、懸濁重合体微粒子の融着が発生する可能性がある。蒸留操作時には、熱効率の観点から懸濁液温と同じ温度にすることが好ましい。
【００７８】
本発明に係る重合装置には、液の撹拌手段として撹拌翼を用いることができる。ここで用いられる撹拌翼としては、懸濁液が滞留なく撹拌されるものならば特に限定されず、パドル翼、タービン翼、アンカー翼などの一般的な撹拌翼や市販のフルゾーン翼（神鋼パンテック社製）、マックスブレンド翼（住友重機社製）等を利用することができる。このうち、撹拌効率の点からフルゾーン翼、マックスブレンド翼が好ましく、特にフルゾーン翼が好ましく用いられる。
【００７９】
また、本発明に係る蒸留装置においても、蒸留効率の観点から撹拌装置を用いることができるが、その際には上記重合装置で用いられるものと同様の撹拌翼が選択される。
【００８０】
本発明に用いられる重合装置の好ましい様態を図を用いて説明する。
【００８１】
図４は本発明に係る重合装置の一実施形態を示す。本重合装置は重合容器１、撹拌機軸２、撹拌翼３、撹拌モーター４、加熱ジャケット５、原材料投入口６、壁面洗浄用としてフルコーンまたはホローコーンタイプのスプレー７、撹拌機軸用のフラットタイプのスプレー８、液排出口９を有する。符号１０は懸濁液の液面を示す。
【００８２】
図５および図６は本発明に係る重合装置の他の実施形態を示し、それぞれ立面図および平面図を表わす。両図において同一の符号は同一の部材を示す。本重合装置は重合容器１１、撹拌機軸１２、撹拌翼１３、撹拌モーター１４、加熱ジャケット１５、原材料投入口１６、リング状の洗浄水導水管１７、壁面洗浄用として１７に等間隔に配置されたフラットタイプのスプレー１８、撹拌機軸用のフラットタイプのスプレー１９、液排出口２０を有する。符号２１は懸濁液の液面を示す。
【００８３】
次に、本発明に用いられる蒸留装置の好ましい一様態を図７を用いて説明する。本蒸留装置は蒸留容器３１、撹拌機軸３２、撹拌翼３３、撹拌モーター３４、加熱ジャケット３５、原材料投入口３６、壁面洗浄用としてフルコーンまたはホローコーンタイプのスプレー３７、撹拌機軸用のフラットタイプのスプレー３８および液排出口３９を有する。符号４０は蒸留の留分の取り出し口を示し、必要ならばコンデンサーを接続し留分を凝縮させて取り出す。また、容器内の減圧が必要な場合は、留分の取り出し口４０を真空ポンプなどの減圧装置に接続することができる。符号４１は懸濁液の液面を示す。
【００８４】
図８および図９は本発明に係る蒸留装置の他の実施形態を示し、それぞれ立面図および平面図を表わす。両図において同一の符号は同一の部材を示す。本蒸留装置は蒸留容器５１、撹拌機軸５２、撹拌翼５３、撹拌モーター５４、加熱ジャケット５５、原材料投入口５６、リング状の洗浄水導水管５７、壁面洗浄用として５７に等間隔に配置されたフラットタイプのスプレー５８、撹拌機軸用のフラットタイプのスプレー５９、液排出口６０を有する。符号６１は蒸留の留分の取り出し口を示し、必要ならばコンデンサーを接続し留分を凝縮させて取り出す。また、容器内の減圧が必要な場合は、留分の取り出し口６１を真空ポンプなどの減圧装置に接続することができる。符号６２は懸濁液の液面を示す。
【００８５】
【実施例】
以下、本発明を実施例および比較例により具体的に説明するが、本発明はこれらによってなんら限定されるものではない。
【００８６】
本発明で用いた各測定方法について以下に述べる。
【００８７】
（１）粒度分布および体積平均粒径の測定
１％塩化ナトリウム水溶液１００〜１５０ｍｌ中に界面活性剤としてアルキルベンゼンスルホン酸塩を０．１〜５ｍｌ加え、さらに測定試料を０．５〜５０ｍｇ加えた。この溶液を、超音波分散機で約１〜３分間分散処理を行ったのち、コールターマルチサイザー（コールター社製）により、１００μｍアパチャーを用いて２〜４０μｍの粒子の粒度分布を測定し、体積平均分布、個数平均分布を求め、これより体積平均粒径を得た。
【００８８】
（２）画質
得られたトナー粒子に対して、ＢＥＴ法による比表面積が２００ｍ²／ｇである疎水性シリカを０．７質量％となるよう外添した。この外添されたトナーが８質量％となるように、アクリル樹脂でコートされたフェライトキャリアを混合し、二成分系現像剤を得た。この現像剤を変動のない環境下において、キヤノン製フルカラー複写機ＣＬＣ７００の改造機を用いて連続通紙による画出し耐久試験を行い、目視にて画像濃度の変動やムラ等を評価した。
【００８９】
（３）カブリの測定
カブリの測定は、ＲＥＦＬＥＣＴＯＭＥＴＥＲ ＭＯＤＥＬ ＴＣ−６ＤＳ（東京電色社製）を使用して測定し、下記式より算出した。数値が小さいほど、カブリが少ないことを示す。
【００９０】
カブリ（反射率）（％）＝標準紙の反射率（％）−サンプルの非画像部の反射率（％）
【００９１】
（４）トナーの摩擦帯電量の測定
トナーの摩擦帯電量は、変動のない環境下にトナー及びキャリアを一昼夜放置した後、ブローオフ法に基づき、次の要領で摩擦帯電量を測定した。
【００９２】
図１０はトナーの摩擦帯電量を測定する装置の説明図である。先ず、底に５００メッシュのスクリーン７３のある金属製の測定容器７２に摩擦帯電量を測定しようとするトナーとキャリアの質量比８：９２の混合物を５０〜１００ｍｌ容量のポリエチレン製のビンに入れ、２００回手で振盪し、該混合物（現像剤）約０．２ｇを入れ金属製のフタ７４をする。このときの測定容器７２全体の質量を秤り、Ｗ₁（ｇ）とする。次に、吸引機７１（測定容器７２と接する部分は少なくとも絶縁体）において、吸引口７７から吸引し風量調節弁７６を調整して真空計７５の圧力を２４５０Ｐａとする。この状態で２分間吸引を行いトナーを吸引除去する。このときの電位計７９が示した電位の最高値をＶ（ボルト）とする。ここで７８はコンデンサーであり容量をＣ（μＦ）とする。また、吸引後の測定容器全体の質量を秤りＷ₂（ｇ）とする。このトナーの摩擦帯電量（ｍＣ／ｋｇ）は下式の如く計算される。
【００９３】
摩擦帯電量（ｍＣ／ｋｇ）＝Ｃ×Ｖ÷（Ｗ₁−Ｗ₂）
【００９４】
（５）不定形トナーの存在率
走査型電子顕微鏡を用いトナーを観察し、不定形トナーの存在率を算出した。不定形トナーの存在率（％）は下式のごとく計算される。
【００９５】
不定形トナー存在率（％）＝不定形トナーの個数÷全トナーの個数×１００
【００９６】
実施例１
下記のようにして、水性分散媒及び重合性単量体組成物をおのおの調製した。
【００９７】
（水性分散媒の調製）
内容積１６０リットルの容器中で、下記の成分を混合し、６０℃に加温した後、高速回転剪断撹拌機クレアミックス（エム・テクニック（株）製）を用いて回転数３７００回転／分で撹拌した。
・水 ９８．４質量部
・Ｎａ₃ＰＯ₄ １．０質量部
【００９８】
次に、容器内を窒素置換すると共に、これにＣａＣｌ₂を０．６質量部添加して反応させ、Ｃａ₃（ＰＯ₄）₂の微粒子を含む水性分散媒を得た。
【００９９】
（重合性単量体組成物の調製）
・スチレン単量体 ６３．９質量部
・ｎ−ブチルアクリレート単量体 １３．１質量部
・キナクリドン系顔料 ６．２質量部
・テレフタル酸−プロピレンオキサイド変性ビスフェノールＡ ３．９質量部
・ジビニルベンセン ０．２質量部
・ジ−ｔｅｒｔ−ブチルサリチル酸アルミニウム化合物 ０．８質量部
・エステルワックス（離型剤Ｎｏ．５） ９．６質量部
上記した成分のうちスチレン単量体の一部、キナクリドン系顔料、ジ−ｔｅｒｔ−ブチルサリチル酸アルミニウム化合物を混合し、ハンディミル（三井鉱山（株）製）を用い５時間分散させた後、スチレン単量体の残部、その他の組成物を加えて６０℃に加温して十分に相溶するまで混合した。その後、これに重合開始剤である２，２’−アゾビス（２，４−ジメチルバレロニトリル）２．３質量部を添加して重合性単量体組成物とした。
【０１００】
上記で調製した水性分散媒中に、上記で調製した重合性単量体組成物を投入して、クレアミックスの回転数を３７００回転／分とし１０分間撹拌し造粒を行った。
【０１０１】
（重合工程）
上記の工程で造粒した懸濁液を、図４に示す重合装置（器壁用スプレーはフルコーンタイプ）に導入し、撹拌翼の回転数１００回転／分、液温６０℃で重合を行った。５時間経過後、重合温度を８０℃に昇温し、加熱撹拌をさらに３時間継続して重合を完了させた。重合工程の間中、器壁用スプレーおよび撹拌機軸用スプレーにより、５分につき３秒間の頻度で間歇的に６０℃の温水を散布した。その他のスプレー条件を表１に示す。
【０１０２】
【表１】

【０１０３】
（トナー及び付着状況の評価）
重合装置中の懸濁液が降温した後、重合装置より懸濁液を排出させ、これに希塩酸を添加してトナー粒子表面に固着した分散剤を溶解し、固液分離後、水洗、ろ過、乾燥することにより重合トナー粒子を得た。不定形トナーの存在率は０．２％であった。トナー粒子の粒度分布を測定したところ、体積平均粒径は７．５μｍで、粒度分布もシャープであり、摩擦帯電量は−４１（μＣ／ｇ）と高い値を示した。また、懸濁液排出後の重合容器内を調べたところ、壁面および撹拌機軸表面に乾燥質量で３３．１ｇのスケール状付着物が生成していたが、付着物の除去を行わずに繰り返しトナー製造を行っても、全く問題ないレベルであった。
【０１０４】
次に、得られたトナー粒子に疎水性シリカを外添し、アクリル樹脂で被覆したフェライトキャリアを混合して二成分系の現像剤とした。２００００枚の画出し試験を行ったところ、カブリは０．２％で終始画像濃度に変動もムラもなく、鮮明且つ定着性の優れた画像が安定して得られた。
【０１０５】
実施例２
スプレー角度およびスプレー衝撃力を表２のように設定した以外は、実施例１と全く同様にしてトナーを得た。不定形トナーの存在率は０．２％であった。トナー粒子の粒度分布を測定したところ、体積平均粒径は７．４μｍで、粒度分布は実施例１とほぼ同様であった。摩擦帯電量は−３９（μＣ／ｇ）であった。スケール状付着物の量は乾燥質量で合計３４．０ｇであり、付着物の除去を行わずに繰り返しトナーの製造を行っても、問題ないレベルであった。
【０１０６】
次に、実施例１と同様に２００００枚の画出し試験を行ったところ、カブリは０．３％で終始画像濃度に変動もムラもなく、鮮明且つ定着性の優れた画像が安定して得られた。
【０１０７】
【表２】

【０１０８】
比較例１
撹拌機軸用スプレーを使用しないこと以外は、実施例１と全く同様にしてトナーを得た。不定形トナーの存在率は２．５％であった。トナー粒子の粒度分布を測定したところ、体積平均粒径は７．７μｍで、粒度分布は実施例１とほぼ同様であった。摩擦帯電量は−３３（μＣ／ｇ）であった。スケール付着物の量は乾燥質量で合計９１．３ｇであり、一部剥離して脱落しており、付着物除去を行わないと繰り返し製造ができない状況であった。
【０１０９】
次に、実施例１と同様に２００００枚の画出し試験を行ったところ、カブリは１．１％で初期には画像濃度に変動もムラもなく、安定した画像が得られたが、後半に白い筋やムラが発生した。
【０１１０】
比較例２
スプレー角度およびスプレー衝撃力を表３のように設定した以外は、実施例１と全く同様にしてトナーを得た。不定形トナーの存在率は３．４％であった。トナー粒子の粒度分布を測定したところ、体積平均粒径は７．８μｍで、粒度分布は実施例１とほぼ同様であった。摩擦帯電量は−３０（μＣ／ｇ）であった。スケール状付着物の量は乾燥質量で合計１２０．８ｇであり、一部剥離して脱落しており、付着物除去を行わないと繰り返し製造ができない状況であった。
【０１１１】
次に、実施例１と同様に２００００枚の画出し試験を行ったところ、カブリは１．２％で比較例１より早い時期に白い筋やムラが発生した。
【０１１２】
【表３】

【０１１３】
実施例３
重合工程までを実施例１と全く同様に行った後に、重合装置から懸濁液を排出させ、これを図８に示す蒸留装置に導入し、撹拌翼の回転数１００回転／分、液温８０℃、蒸留容器内圧力４９．３ｋＰａ（絶対圧）で蒸留を行った。蒸留工程の間中、器壁用スプレーおよび撹拌機軸用スプレーにより、２分につき２秒間の頻度で間歇的に８０℃の温水を散布した。その他のスプレーの条件を表４に示す。
【０１１４】
【表４】

【０１１５】
蒸留工程終了後、トナーの評価を行ったところ、不定形トナーの存在率は０．３％であった。トナー粒子の粒度分布を測定したところ、体積平均粒径は７．６μｍで、粒度分布は実施例１とほぼ同様であった。摩擦帯電量は−４２（μＣ／ｇ）であった。スケール状付着物の量は乾燥質量で合計３５．２ｇであり、付着物の除去を行わずに繰り返しトナーの製造を行っても、問題ないレベルであった。
【０１１６】
次に、実施例１と同様に２００００枚の画出し試験を行ったところ、カブリは０．５％で終始画像濃度に変動もムラもなく、鮮明且つ定着性の優れた画像が安定して得られた。
【０１１７】
実施例４
スプレー角度およびスプレー衝撃力を表５のように設定した以外は、実施例３と全く同様にしてトナーを得た。不定形トナーの存在率は０．２％であった。トナー粒子の粒度分布を測定したところ、体積平均粒径は７．２μｍで、粒度分布は実施例１とほぼ同様であった。摩擦帯電量は−４４（μＣ／ｇ）であった。スケール状付着物の量は乾燥質量で合計３１．９ｇであり、付着物の除去を行わずに繰り返しトナーの製造を行っても、問題ないレベルであった。
【０１１８】
次に、実施例１と同様に２００００枚の画出し試験を行ったところ、カブリは０．４％で終始画像濃度に変動もムラもなく、鮮明且つ定着性の優れた画像が安定して得られた。
【０１１９】
【表５】

【０１２０】
比較例３
蒸留工程中の撹拌機用スプレーのスプレー衝撃力を１．７×１０³Ｐａとした以外は、実施例３と全く同様にしてトナーを得た。不定形トナーの存在率は５．９％であった。トナー粒子の粒度分布を測定したところ、体積平均粒径は７．６μｍで、粒度分布は実施例１とほぼ同様であった。摩擦帯電量は−３３（μＣ／ｇ）であった。スケール状付着物の量は乾燥質量で合計１０２．４ｇであり、通常は見られない蒸留容器天面付近への付着が観察された。これは撹拌機軸用スプレーのスプレー衝撃力が大きすぎ、懸濁液の液はねが起こったためと考えられる。また、スケール状付着物は一部剥離して脱落しており、付着物除去を行わないと繰り返し製造ができない状況であった。
【０１２１】
次に、実施例１と同様に２００００枚の画出し試験を行ったところ、カブリは１．７％で初期には安定した画像が得られたが、比較例１より早い時期に白い筋やムラが発生した。また感光体上にわずかにフィルミングの発生が見られた。
【０１２２】
【発明の効果】
本発明によれば、懸濁重合法によるトナーの製造工程において、重合／蒸留装置を構成する部材のうち、重合／蒸留容器の気相部に露出した部分上に、スケール状付着物が生成するのを抑制することができる。該付着物が剥離し、通常の粒径が揃った球形のトナーに混入すると、不定形トナーとなり、トナーの性能を低下させるが、本発明によれば、該付着物の生成が著しく減少するため、その除去作業が本質的に不要になり、かつ画像形成を行った際に、画像濃度に変動もムラもなく、鮮明且つ定着性の優れた画像が安定して得られるトナーを得ることができる。
【図面の簡単な説明】
【図１】フルコーンスプレーの噴霧パターンを示す図である。
【図２】ホローコーンスプレーの噴霧パターンを示す図である。
【図３】フラットスプレーの噴霧パターンを示す図である。
【図４】本発明に係る重合装置の一実施形態を示す概略図である。
【図５】本発明に係る重合装置の他の実施形態を示す概略図である。
【図６】本発明に係る重合装置の他の実施形態を示す概略図である。
【図７】本発明に係る蒸留装置の一実施形態を示す概略図である。
【図８】本発明に係る蒸留装置の他の実施形態を示す概略図である。
【図９】本発明に係る蒸留装置の他の実施形態を示す概略図である。
【図１０】トナーの摩擦帯電量を測定する装置の説明図である。
【符号の説明】
１ 重合容器
２，２２ 撹拌機軸
３，２３ 撹拌翼
４，２６ 撹拌モーター
５，２５ 加熱ジャケット
６，２７ 原料投入口
７ フルコーンまたはホローコーンタイプのスプレー
８ フラットタイプのスプレー
９ 液排出口
１０ 懸濁液の液面
３１ 蒸留容器[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing toner by a polymerization method used in electrophotography, electrostatic recording, magnetic recording, toner jet recording and the like.
[0002]
[Prior art]
Conventionally, as an electrophotographic method, many methods are known as described in U.S. Pat. No. 2,297,691, Japanese Patent Publication Nos. 42-23910 and 43-24748, etc. In general, a photoconductive substance is used to form an electrical latent image on a photoreceptor by various means, and then the latent image is developed with toner, and a toner image is formed on a transfer material such as paper as necessary. Is transferred and fixed by heat / pressure to obtain a copy image. Various methods have been proposed in the past for developing using toner or fixing a toner image.
[0003]
The toner is required to have excellent fluidity and stable triboelectric chargeability, and to be capable of high-quality printing without causing fogging on the photoconductor and a decrease in image density over a long period of time. If the fluidity of the toner is poor, the developer will be poorly supplied and the image will be blurred or the image density will be reduced. Further, defective cleaning occurs, and the developer remains on the photoreceptor to cause fogging or toner filming. When a toner film is formed on the photoreceptor, white spots and black stains are generated on the image, and the image quality is degraded.
[0004]
It is desirable that the toner exhibits excellent fluidity and has a spherical shape and a small particle size distribution in order to form a high quality image.
[0005]
Conventionally, toners used for these purposes have generally been produced as toners having a desired particle size by a fine pulverizer and a classifier after melt-mixing and uniformly dispersing a colorant comprising a dye and pigment in a thermoplastic resin. .
[0006]
While this method of manufacture can produce fairly good toners, it has certain limitations, i.e., limited choice of toner materials. For example, the resin colorant dispersion must be sufficiently brittle and capable of being finely pulverized with economically possible production equipment. However, if the resin colorant dispersion is made brittle to satisfy these requirements, the particle size range of the particles formed when actually pulverized at high speed tends to be widened. It is included in the problem. In order for a toner to exhibit satisfactory development characteristics, its particle size distribution must be somewhat narrow. Therefore, it is necessary to classify particles obtained by pulverization to remove coarse particles and fine particles. Therefore, the pulverization method has a poor yield and a low toner yield.
[0007]
Further, such a brittle material is susceptible to further pulverization or pulverization when used for development in a copying machine or the like, which adversely affects the developability.
[0008]
Also, with this method, it is difficult to completely disperse solid fine particles such as a colorant in the resin. Depending on the degree of dispersion, fogging may increase, image density may decrease, and color mixing / transparency may be poor. Careful attention must be paid to the dispersion of the colorant as this is a cause. Further, exposure of the colorant to the fracture surface of the pulverized particles may cause a change in development characteristics. Furthermore, it is difficult to produce a spherical toner with a uniform surface by the pulverization method, and it is difficult to obtain a toner that is satisfactory in terms of fluidity and triboelectric charging.
[0009]
In addition, in the toner by these pulverization methods, there is a restriction when adding a releasing material such as wax. That is, in order to achieve a sufficient level of dispersibility of the releasable substance, (1) it is necessary to maintain a certain viscosity at the kneading temperature with the resin, and (2) the content of the releasable substance is reduced to about For example, the content may be 5% by mass or less. Due to such restrictions, there is a limit to the toner fixability by the pulverization method.
[0010]
In order to overcome the problems of the toner by the pulverization method, various polymerization method toners such as suspension polymerization method toners disclosed in Japanese Patent Publication Nos. 36-10231, 43-10799, and 51-14895 are disclosed. The manufacturing method has been proposed. For example, in a suspension polymerization toner, a monomer composition is obtained by uniformly dissolving or dispersing a polymerizable monomer, a colorant, a polymerization initiator, and, if necessary, a crosslinking agent, a charge control agent, and other additives. After that, the monomer composition is dispersed in a continuous phase containing a dispersion stabilizer, for example, an aqueous phase by using a suitable stirrer, and at the same time, a polymerization reaction is performed to obtain toner particles having a desired particle size. obtain. Since this method does not include any pulverization step, the toner does not need to be brittle, a soft material can be used as the resin, and there is no exposure of the colorant to the particle surface, which is uniform. There is an advantage of having triboelectric chargeability. Further, since the particle size distribution of the obtained toner is relatively sharp, the toner can be obtained in high yield even if the classification step is omitted or classified. Furthermore, according to this method, in addition to the restriction imposed on the above pulverized toner, the wax can be surely included, and good fixing properties and offset resistance can be obtained. The polymerized toner obtained by this method is spherical and has a uniform surface and exhibits good development characteristics.
[0011]
As described above, since the polymerization toner by suspension polymerization generally has a uniform shape close to a sphere, the fluidity and transferability are good, and even after a large number of continuous developments, there is little stress on the toner, and the photoconductor It has the feature that there is little occurrence of filming.
[0012]
However, when the polymerization toner is closely observed, it has been found that there is a slight amount of colorless toner (hereinafter referred to as “amorphous toner”) containing no irregular shape or colorant. Amorphous toners are considered to be produced in a different process from normal polymerized toners. If this ratio is increased, toner characteristics such as triboelectric chargeability and development characteristics when image evaluations are adversely affected, image density fluctuations, whiteness Generation of streaks and fog is observed. Therefore, preventing the generation of irregular shaped toner in the production method of polymerized toner is an important matter not only in terms of toner characteristics but also in production cost.
[0013]
[Problems to be solved by the invention]
As a cause of generation of the irregular toner in the above-mentioned polymerization toner,
(1). Unreacted polymerizable monomer vapor condenses on the surface of the member protruding into the gas phase part in the container and is heated and polymerized in the gas phase part, resulting in a composition different from the normal polymerization reaction in the liquid phase / The in-process polymer is formed and deposited / deposited.
(2). Due to the splashing or foaming of the suspension polymerization reaction solution, the suspension polymer fine particles adhere to the surface of the member protruding into the gas phase portion in the container and are dried / solidified by heat. When the surface temperature of the incidental device is higher than the glass transition temperature of the polymer produced by polymerization of the polymerizable monomer, fusion occurs and adhesion becomes strong.
(3). The above (1) and (2) occur in combination.
It is well known that the generated scale-like deposits are mixed into the product by peeling off and observed as an irregular toner.
[0014]
It was also found that if the scale-like deposit grows to a sufficient size and then peels / drops off, it can cause clogging or sticking in piping or valves connected to the polymerization vessel or distillation vessel. . This is not preferable because it requires frequent removal work of scale-like deposits, leading to a reduction in the operating rate of the manufacturing apparatus, resulting in an increase in the cost of the product toner. In order to prevent the scale-like deposits, for example, as described in JP-A-10-153878, a method of spraying water or a dispersion medium at a wide angle by spraying on a gas phase portion of a polymerization vessel has been proposed. However, in this method, when there are other device members such as a stirrer shaft, baffle plate, nozzle, etc. in the gas phase part of the container, there is a part where spraying is not performed or adjustment of the appropriate spray intensity for the spray target. Therefore, sufficient effects cannot be obtained, such as insufficient cleaning or conversely encouraging splashing of liquid to enlarge the adhesion area.
[0015]
Accordingly, an object of the present invention is to generate scale-like deposits on the surface of the polymerization vessel and the portion of the distillation vessel that protrudes from the vapor phase portion of the polymerization vessel and distillation device in the polymerization step and distillation step. Another object of the present invention is to provide a method for producing a polymerization toner that is not allowed to occur.
[0016]
[Means for Solving the Problems]
As a result of intensive studies to suppress the formation of scale-like deposits in the polymerization and distillation steps, the present inventors have found that the polymerization vessel and the vapor phase portion of the distillation vessel are among the components constituting the distillation device. When spraying water or hot water on the exposed parts, a dedicated spray is placed on each member and the spray impact force per unit area is set to an appropriate value. It has been found that the suspended polymer particles adhering to the surface by splashing or foaming and the unreacted monomer condensed on the surface of the portion can be washed away reliably and can be prevented from scaling. Further, since the spray impact force per unit area is appropriately set, no excessive splashing occurs.
[0017]
The “spray impact force per unit area” here refers to the pressure applied by sprayed water or hot water per unit area of the target surface, and the appropriate spray type, spray angle, and spray operation pressure. It can control by selecting to.
[0018]
Based on the above knowledge, the present inventors have completed the invention. That is, according to the present invention, a polymerizable monomer composition containing at least a polymerizable monomer and a colorant is dispersed in an aqueous dispersion medium and polymerized, and then, if necessary, subsequently subjected to a distillation operation. In a method for producing a polymerization method toner comprising colored polymer particles obtained through a step of removing unreacted polymerizable monomer out of the system, a polymerization vessel and a distillation are among the members constituting the polymerization device and the distillation device. Using a dedicated spray nozzle for each portion exposed to the gas phase part of the container, the spray impact force per unit area of water or hot water on the target surface is 2.0 to 1.1 × 10^ThreeThere is provided a method for producing a toner, wherein the toner is sprayed so as to be Pa.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail.
[0020]
As a method for producing the polymerization toner of the present invention, a release agent, a colorant and, if necessary, a charge control agent, a polymerization initiator, a crosslinking agent, and other additives are added to the polymerizable monomer, and a normal stirring is performed. A stirrer having a high shearing force such as CLEARMIX or Homomixer in a polymerizable monomer composition that has been uniformly dissolved or dispersed by a machine, a homogenizer, an ultrasonic disperser or the like in an aqueous medium containing a dispersion stabilizer Then, the mixture is granulated by adjusting the stirring speed / time so that the droplets of the polymerizable monomer composition have a desired toner particle size. In the suspension polymerization method, it is usually preferable to use 100 to 3000 parts by mass of an aqueous dispersion medium with respect to 100 parts by mass of the polymerizable monomer composition. After granulation, since the droplet state is maintained by the action of the dispersion stabilizer, stirring may be performed to such an extent that the droplets are prevented from settling. Polymerization is carried out at a polymerization temperature of 40 ° C. or higher, generally 50 to 90 ° C. Further, the temperature may be raised in the latter half of the polymerization reaction for the purpose of obtaining a desired molecular weight distribution. Further, in order to remove unreacted polymerizable monomers and by-products, the distillation operation is performed in the latter half of the reaction or after the completion of the reaction. May be performed. The distillation operation can be performed under normal pressure or reduced pressure. After completion of the polymerization reaction and / or distillation operation, the produced toner particles are filtered / washed, but acid and / or alkali treatment may be performed before or after this step. The toner particles finally separated from the liquid phase are dried by a known method.
[0021]
As the polymerizable monomer used in the toner of the present invention, a vinyl polymerizable monomer capable of radical polymerization is used. As the vinyl polymerizable monomer, a monofunctional polymerizable monomer or a polyfunctional polymerizable monomer can be used. Monofunctional polymerizable monomers include styrene, α-methyl styrene, β-methyl styrene, o-methyl styrene, m-methyl styrene, p-methyl styrene, 2,4-dimethyl styrene, pn-butyl. Styrene, p-tert-butyl styrene, pn-hexyl styrene, pn-octyl styrene, pn-nonyl styrene, pn-decyl styrene, pn-dodecyl styrene, p-methoxy styrene, p -Styrene derivatives such as phenylstyrene; methyl acrylate, ethyl acrylate, n-propyl acrylate, iso-propyl acrylate, n-butyl acrylate, iso-butyl acrylate, tert-butyl acrylate, n-amyl acrylate, n-hexyl acrylate, 2 -Ethylhexyl acrylate , Acrylic polymerizable monomers such as n-octyl acrylate, n-nonyl acrylate, cyclohexyl acrylate, benzyl acrylate, dimethyl phosphate ethyl acrylate, diethyl phosphate ethyl acrylate, dibutyl phosphate ethyl acrylate, 2-benzoyloxyethyl acrylate Methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, iso-propyl methacrylate, n-butyl methacrylate, iso-butyl methacrylate, tert-butyl methacrylate, n-amyl methacrylate, n-hexyl methacrylate, 2-ethylhexyl methacrylate, n-octyl Methacrylate, n-nonyl methacrylate, diethyl phosphate ethyl methacrylate Methacrylic polymerizable monomers such as dibutyl phosphate ethyl methacrylate; methylene aliphatic monocarboxylic acid esters; vinyl esters such as vinyl acetate, vinyl propionate, vinyl butyrate, vinyl benzoate, vinyl formate; vinyl methyl ether Vinyl ether such as vinyl ethyl ether and vinyl isobutyl ether; vinyl ketone such as vinyl methyl ketone, vinyl hexyl ketone and vinyl isopropyl ketone.
[0022]
As polyfunctional polymerizable monomers, diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, tripropylene glycol Diacrylate, polypropylene glycol diacrylate, 2,2′-bis (4- (acryloxydiethoxy) phenyl) propane, trimethylolpropane triacrylate, tetramethylolmethane tetraacrylate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol Dimethacrylate, tetraethylene glycol dimethacrylate, polyethylene glycol Dimethacrylate, 1,3-butylene glycol dimethacrylate, 1,6-hexanediol dimethacrylate, neopentyl glycol dimethacrylate, polypropylene glycol dimethacrylate, 2,2'-bis (4- (methacryloxy-diethoxy) phenyl) propane, Examples include 2,2′-bis (4- (methacryloxy / polyethoxy) phenyl) propane, trimethylolpropane trimethacrylate, tetramethylolmethane tetramethacrylate, divinylbenzene, divinylnaphthalene, and divinyl ether.
[0023]
In the present invention, the above monofunctional polymerizable monomers are used alone or in combination of two or more, or the above monofunctional polymerizable monomers and polyfunctional polymerizable monomers are used in combination. To do. Among the polymerizable monomers described above, styrene or a styrene derivative is preferably used alone or in combination, or in combination with other monomers from the viewpoint of toner development characteristics and durability.
[0024]
Examples of the colorant used in the present invention include carbon black, iron black, C.I. I. Direct Red 1, C.I. I. Direct Red 4, C.I. I. Acid Red 1, C.I. I. Basic Red 1, C.I. I. Modern Tread 30, C.I. I. Direct Blue 1, C.I. I. Direct Blue 2, C.I. I. Acid Blue 9, C.I. I. Acid Blue 15, C.I. I. Basic Blue 3, C.I. I. Basic Blue 5, C.I. I. Modern Blue 7, C.I. I. Direct Green 6, C.I. I. Basic Green 4, C.I. I. Dyes such as Basic Green 6; yellow lead, cadmium yellow, mineral fast yellow, navel yellow, naphthol yellow S, Hansa Yellow G, permanent yellow NCG, tartrazine lake, molybdenum orange, permanent orange GTR, benzidine orange G, cadmium Red, Permanent Red 4R, Watching Red Calcium Salt, Brilliant Carmine 3B, Fast Violet B, Methyl Violet Lake, Bitumen, Cobalt Blue, Alkaline Blue Lake, Victoria Blue Lake, Quinacridone, Rhodamine Lake, Phthalocyanine Blue, Fast Sky Blue, Pigment Green And pigments such as B, malachite green lake, and final yellow green G.
[0025]
In the present invention in which polymerization is carried out in an aqueous dispersion medium, it is necessary to pay attention to the polymerization inhibitory property and water phase transferability of the colorant, preferably surface modification, for example, a hydrophobic treatment with a substance that does not inhibit polymerization It is better to have applied. In particular, dyes and carbon blacks have many polymerization inhibiting properties, so care must be taken when using them. A preferable method for surface-treating the dye system includes a method in which a polymerizable monomer is polymerized in the presence of these dyes in advance, and the obtained colored polymer is added to the monomer system. In addition to carbon black, the carbon black may be grafted with a substance that reacts with the surface functional group of the carbon black, such as polyorganosiloxane. In the present invention, a magnetic material may be added, but it is also preferable to use this after surface treatment.
[0026]
In the present invention, a release agent may be contained in the polymerizable monomer composition. As the release agent, a wax in a solid state at room temperature is preferable, and a solid wax having a melting point of 40 to 100 ° C. is particularly preferable in terms of toner blocking resistance, durability of a large number of sheets, low-temperature fixability, and offset resistance.
[0027]
Examples of the wax include paraffin wax, polyolefin wax, microcrystalline wax, polymethylene wax such as Fischer-Tropsch wax, amide wax, higher fatty acid, long chain alcohol, ester wax, and derivatives thereof such as graft compounds and block compounds. These preferably have a sharp maximum endothermic peak in the DSC endothermic curve from which low molecular weight components have been removed.
[0028]
Examples of the wax preferably used include linear alkyl alcohols having 15 to 100 carbon atoms, linear fatty acids, linear acid amides, linear esters, and montan derivatives. Those from which impurities such as liquid fatty acids have been previously removed from these waxes are also preferred.
[0029]
Further, the wax preferably used is a low molecular weight alkylene polymer obtained by polymerizing alkylene with radical polymerization under high pressure or Ziegler catalyst or other catalyst under low pressure; alkylene obtained by thermally decomposing high molecular weight alkylene polymer Polymer: A low molecular weight alkylene polymer produced as a by-product during polymerization of alkylene, separated and purified; a hydrocarbon polymer distillation residue obtained by the age method from a synthesis gas consisting of carbon monoxide and hydrogen, or a distillation residue is hydrogenated Examples thereof include polymethylene wax obtained by extracting and fractionating specific components from the synthetic hydrocarbon obtained by addition. These waxes may contain an antioxidant.
[0030]
In order to improve the translucency of the fixed image, a solid ester wax is preferable, and a solid ester wax having a melting point of 40 to 100 ° C. is particularly preferable.
[0031]
The ester wax used in the present invention is formed from a compound represented by the following general formulas (I) to (VI) and has a melting point of 40 to 100 ° C.
[0032]
[Chemical 1]

(Wherein, a and b are integers from 0 to 4, and a + b is 4. R₁And R₂Is an organic group having 1 to 40 carbon atoms, R₁And R₂And the carbon number difference is 3 or more. m and n are integers of 0 to 25, and m and n are not 0 at the same time. )
[0033]
[Chemical 2]

(In the formula, a and b are integers of 0 to 3, and a + b is 1 to 3. R₁And R₂Is an organic group having 1 to 40 carbon atoms, R₁And R₂And the carbon number difference is 3 or more. R_ThreeIs a hydrogen atom or an organic group having 1 or more carbon atoms. However, when a + b = 2, R_ThreeOne of these is an organic group having 1 or more carbon atoms. k is an integer of 1 to 3. m and n are integers of 0 to 25, and m and n are not 0 at the same time. )
[0034]
[Chemical Formula 3]

(Wherein R₁And R_ThreeIs an organic group having 6 to 32 carbon atoms, R₁And R_ThreeMay or may not be the same. R₂Represents an organic group having 1 to 20 carbon atoms. )
[0035]
[Formula 4]

(Wherein R₁And R₂Is an organic group having 6 to 32 carbon atoms, R₁And R_ThreeMay or may not be the same.
R₂Is -CH₂CH₂OC₆H_FourOCH₂CH₂−,

[0036]
[Chemical formula 5]

(In the formula, a is an integer of 0 to 4, b is an integer of 1 to 4, and a + b is 4.₁Is an organic group having 1 to 40 carbon atoms. m and n are integers of 0 to 25, and m and n are not 0 at the same time. )
[0037]
[Chemical 6]

(Wherein R₁And R₂Denote the same or different hydrocarbon groups having 15 to 45 carbon atoms. )
[0038]
The melting point of the ester wax is preferably 40 to 100 ° C. When the melting point is less than 40 ° C., the toner has insufficient blocking resistance and shape retention, and when it exceeds 100 ° C., the releasing effect becomes insufficient. The following are illustrated as an ester wax as a mold release agent which consists of ester compounds.
[0039]
[Chemical 7]

[0040]
[Chemical 8]

[0041]
When the releasing agent is an ester wax having an ester compound having the above structural formula, it exhibits good transparency and exhibits good fixability when incorporated in toner particles.
[0042]
In the present invention, the mold release agent is blended in an amount of 5 to 40 parts by mass (more preferably 10 to 30 parts by mass) with respect to 100 parts by mass of the polymerizable monomer. The release agent may be contained in 5 to 40 parts by mass (more preferably 10 to 30 parts by mass) of toner particles per 100 parts by mass of the produced binder resin.
[0043]
The toner of the present invention may contain a charge control agent.
[0044]
Known charge control agents can be used. For example, organometallic compounds and chelate compounds are effective for controlling the toner to be negatively charged, and monoazo metal compounds, acetylacetone metal compounds, aromatic hydroxycarboxylic compounds are effective. There are metal compounds of acids and aromatic dicarboxylic acids. Other examples include aromatic hydroxycarboxylic acids, aromatic mono- and polycarboxylic acids and metal salts thereof, anhydrides, esters, and phenol derivatives such as bisphenol.
[0045]
Further, urea derivatives, metal-containing salicylic acid compounds, quaternary ammonium salts, calixarene, silicon compounds, styrene-acrylic acid copolymers, styrene-methacrylic acid copolymers, styrene-acrylic sulfonic acid copolymers, nonmetal carboxylic acids System compounds and the like.
[0046]
Examples of toners that are controlled to be positively charged include modified products of nigrosine and fatty acid metal salts, quaternary ammonium salts such as tributylbenzylammonium-1-hydroxy-4-naphthosulfonate, tetrabutylammonium tetrafluoroborate, And onium salts such as phosphonium salts thereof and their lake pigments, triphenylmethane dyes and their lake pigments (as rake agents, phosphotungstic acid, phosphomolybdic acid, phosphotungsten molybdic acid, tannic acid) , Lauric acid, gallic acid, ferricyanide, ferrocyanide, etc.), metal salts of higher fatty acids; siorganotin oxides such as dibutyltin oxide, dioctyltin oxide, dicyclohexyltin oxide; dibutyltin borate Dioctyl tin borate, shea organo tin borate such as dicyclohexyl tin borate; can be used in combination of these alone, or two or more kinds. Among these, a charge control agent such as a nigrosine-type quaternary ammonium salt is particularly preferably used.
[0047]
These charge control agents may be used in an amount of 0.01 to 20 parts by mass (more preferably 0.5 to 10 parts by mass) with respect to 100 parts by mass of the polymerizable monomer.
[0048]
In the case of a color toner, a charge control agent that is colorless, has a high toner charging speed, and can stably maintain a constant charge amount is particularly preferable. Furthermore, in the case of a toner obtained by a polymerization method, a charge control agent having no polymerization inhibition and no solubilized product in an aqueous system is particularly preferable.
[0049]
An appropriate polymerization initiator can also be used when the polymerizable monomer is polymerized. For example, 2,2′-azobis- (2,4-dimethylvaleronitrile), 2,2′-azobisisobutyronitrile, 1,1′-azobis (cyclohexane-1-carbonitrile), 2,2 ′ -Azo polymerization initiators such as azobis-4-methoxy-2,4-dimethylvaleronitrile, azobisisobutyronitrile; benzoyl peroxide, methyl ethyl ketone peroxide, t-butylperoxy-2-ethylhexanoate, diisopropylperoxycarbonate , Peroxide type polymerization initiators such as cumene hydroperoxide, 2,4-dichlorobenzoyl peroxide, lauroyl peroxide, and the like are used. Although the addition amount of this polymerization initiator changes with the target degree of polymerization, generally 0.5-20 mass parts is added and used with respect to 100 mass parts of polymerizable monomers. The kind of the initiator varies slightly depending on the polymerization method, but it can be used alone or in combination with reference to the 10-hour half-life temperature.
[0050]
The polymerizable monomer composition in the present invention may contain a crosslinking agent. Examples of the crosslinking agent include polyfunctional compounds such as divinylbenzene, 4,4′-divinylbiphenyl, ethylene glycol di (meth) acrylate, glycidyl (meth) acrylate, and trimethylolpropane tri (meth) acrylate. it can.
[0051]
Further, as a dispersion stabilizer for satisfactorily dispersing the polymerizable monomer composition in an aqueous medium, for example, inorganic calcium oxides such as tricalcium phosphate, magnesium phosphate, aluminum phosphate, zinc phosphate, carbonic acid Calcium, magnesium carbonate, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, calcium metasilicate, calcium sulfate, barium sulfate, bentonite, silica, alumina, magnetic substance, ferrite and the like can be mentioned. As the organic compound, for example, polyvinyl alcohol, gelatin, methyl cellulose, methyl hydroxypropyl cellulose, ethyl cellulose, sodium salt of carboxymethyl cellulose, starch and the like are used dispersed in an aqueous phase. These dispersion stabilizers are preferably used in an amount of 0.2 to 10.0 parts by mass with respect to 100 parts by mass of the polymerizable monomer.
[0052]
Commercially available dispersion stabilizers may be used as they are, but in order to obtain dispersed particles having a fine and uniform particle size, the inorganic compound can be generated in a dispersion medium under high-speed stirring. . For example, in the case of tricalcium phosphate, a preferable dispersant for the suspension polymerization method can be obtained by mixing an aqueous sodium phosphate solution and an aqueous calcium chloride solution under high-speed stirring. Moreover, you may use together 0.001-0.1 mass part surfactant with respect to 100 mass parts of aqueous media for refinement | miniaturization of these dispersing agents. Specifically, commercially available nonionic, anionic and cationic surfactants can be used, such as sodium dodecyl sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, sodium oleate, sodium laurate, potassium stearate, olein. Acid calcium or the like is preferably used.
[0053]
In the case of a polymerization method using an aqueous dispersion medium such as suspension polymerization, the inclusion of a release agent can be promoted by adding a polar resin to the polymerizable monomer composition. When a polar resin is present in the polymerizable monomer composition dispersed in the aqueous dispersion medium, the polar resin moves to the vicinity of the interface between the aqueous dispersion medium and the polymerizable monomer composition due to the difference in hydrophilicity. The polar resin is unevenly distributed on the toner surface. As a result, the toner particles have a capsule structure, and the inclusion property of the release agent is improved even when a large amount of the release agent is contained.
[0054]
The polar resin is particularly preferably a polyester-based resin since the fluidity of the polar resin itself can be expected when unevenly distributed on the toner surface.
[0055]
Examples of polar resins that can be used in the toner of the present invention include terephthalic acid, isophthalic acid, phthalic acid, fumaric acid, maleic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, Acid component monomers such as sebacic acid, camphoric acid, cyclohexanedicarboxylic acid, trimellitic acid; ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4 -Butanediol, neopentyl glycol, alkylene glycols such as 1,4-bis (hydroxymethyl) cyclohexane and polyalkylene glycols, bisphenol A, hydrogenated bisphenol, ethylene oxide adduct of bisphenol A, bisphenol A B pyrene oxide adducts, glycerol, trimethylolpropane, and such polyhydric alcohols monomer pentaerythritol may be mentioned those condensation polymerization.
[0056]
In using the toner produced according to the present invention, an external additive can be used for the purpose of imparting various properties. The external additive preferably has a particle size of 1/10 or less of the volume average diameter of the toner particles from the viewpoint of durability when added to the toner. The particle size of the additive means the average particle size obtained by observing the surface of the toner particles with an electron microscope. As the external additive, for example, the following are used.
[0057]
Metal oxide (aluminum oxide, titanium oxide, strontium titanate, cerium oxide, magnesium oxide, chromium oxide, tin oxide, zinc oxide, etc.), nitride (silicon nitride, etc.), carbide (silicon carbide, etc.), metal salt (sulfuric acid) Calcium, barium sulfate, calcium carbonate, etc.), fatty acid metal salts (zinc stearate, calcium stearate, etc.), carbon black, silica, etc.
[0058]
These external additives are used in an amount of 0.01 to 10 parts by weight, preferably 0.05 to 5 parts by weight, based on 100 parts by weight of toner particles. These external additives may be used alone or in combination. Those subjected to hydrophobic treatment are more preferred.
[0059]
Furthermore, the toner of the present invention can be used as a magnetic toner containing a magnetic material. In this case, the magnetic material can also serve as a colorant. In the present invention, the magnetic material contained in the magnetic toner includes iron oxides such as magnetite, hematite, and ferrite; metals such as iron, cobalt, nickel, or aluminum, cobalt, copper, lead, magnesium of these metals, Examples thereof include alloys of metals such as tin, zinc, antimony, beryllium, bismuth, cadmium, calcium, manganese, selenium, titanium, tungsten, vanadium, and mixtures thereof.
[0060]
These ferromagnetic materials have an average particle size of 2 μm or less, preferably about 0.1 to 0.5 μm. The amount to be contained in the toner is about 20 to 200 parts by mass, particularly preferably 40 to 150 parts by mass with respect to 100 parts by mass of the polymerizable monomer.
[0061]
Further, the magnetic characteristics when 800 kA / m is applied are coercive force (Hc) of 1.6 to 24 kA / m, and saturation magnetization (σs) of 50 to 200 Am.²/ Kg, residual magnetization (σr) 2-20 Am²/ Kg is preferred.
[0062]
The toner produced according to the present invention can be used in any developer as a one-component or two-component developer. For example, in the case of a magnetic toner in which a magnetic material is contained in the toner as the one-component developer, there is a method of transporting and charging the magnetic toner using a magnet built in the developing sleeve. When non-magnetic toner containing no magnetic material is used, there is a method in which a blade and a fur brush are used to forcibly charge by a developing sleeve, and the toner is attached to the sleeve and conveyed.
[0063]
On the other hand, when used as a two-component developer that is generally used, a carrier is used as a developer together with the toner of the present invention. Although it does not specifically limit as a carrier used for this invention, It is comprised by the single and composite ferrite state which mainly consist of iron, copper, zinc, nickel, cobalt, manganese, and a chromium element. The carrier shape is also important from the viewpoint that the saturation magnetization and electric resistance can be controlled in a wide range. For example, it is preferable to select a spherical shape, a flat shape, an indeterminate shape, etc., and also to control the fine structure of the carrier surface state, for example, the surface unevenness. . Generally, a method is used in which carrier core particles are generated in advance by firing and granulating the above-mentioned inorganic oxide, and then a method of coating the resin is used. From the method of kneading the inorganic oxide and the resin, and then crushing / classifying to obtain a low-density dispersion carrier, and further, the kneaded product of the inorganic oxide and the monomer is directly suspension-polymerized in an aqueous medium to obtain a spherical shape. A method for obtaining a polymerized carrier for obtaining a dispersed carrier can also be used.
[0064]
A system in which the surface of the carrier is coated with a resin or the like is particularly preferable. As the method, any of conventionally known methods such as a method in which a coating material such as a resin is dissolved or suspended in a solvent and applied and adhered to a carrier, or a method of simply mixing with a powder can be applied.
[0065]
The substance to be fixed on the carrier surface varies depending on the toner material. For example, polytetrafluoroethylene, monochlorotrifluoroethylene polymer, polyvinylidene fluoride, silicone resin, polyester resin, metal compound of ditertiary butyl salicylic acid, styrene resin, acrylic It is appropriate to use one or a plurality of resin, polyamide, polyvinyl butyral, nigrosine, aminoacrylate resin, basic dye and its lake, fine silica powder, fine alumina powder, etc., but is not necessarily limited thereto.
[0066]
The treatment amount of the above compound is generally 0.1 to 30 parts by mass, preferably 0.5 to 20 parts by mass with respect to 100 parts by mass of the carrier as a total amount.
[0067]
The average particle size of these carriers is 10 to 100 μm, preferably 20 to 50 μm.
[0068]
A particularly preferred embodiment of the carrier is Cu—Zn—Fe ternary ferrite, the surface of which is a combination of a resin such as a fluorine resin and a styrene resin, for example, polyvinylidene fluoride and a styrene-methyl methacrylate resin; Polytetrafluoroethylene and styrene-methyl methacrylate resin, fluorine copolymer and styrene copolymer; and the like in a mixture of 90:10 to 20:80, preferably 70:30 to 30:70. 0.01 to 5% by mass, preferably 0.1 to 1% by mass, and a coated ferrite carrier having the above average particle diameter in which 250 mesh pass and 400 mesh on carrier particles are 70% by mass or more. Can be mentioned. Examples of the fluorine-based copolymer include vinylidene fluoride-tetrafluoroethylene copolymer (10:90 to 90:10), and examples of the styrene-based copolymer include styrene-2-ethylhexyl acrylate (20:80 to 80:20), styrene-2-ethylhexyl acrylate-methyl methacrylate (20-60: 5-30: 10-50).
[0069]
The coated ferrite carrier has a sharp particle size distribution, provides a preferable triboelectric chargeability for the toner of the present invention, and has an effect of improving electrophotographic characteristics.
[0070]
When a two-component developer is prepared by mixing with the toner in the present invention, the mixing ratio is usually good when the toner concentration in the developer is 2% by mass to 15% by mass, preferably 4% by mass to 13% by mass. Results. If the toner concentration is less than 2% by mass, the image density is low and impractical, and if it exceeds 15% by mass, fogging and in-machine scattering are increased and the useful life of the developer is shortened. Further, the magnetic properties of the carrier are preferably as follows. The strength of magnetization at 80 kA / m after magnetic saturation is 30 to 300 Am²/ Kg is required. In order to achieve higher image quality, preferably 100 to 250 Am²/ Kg is good. 300 Am²When it is larger than / kg, it becomes difficult to obtain a high-quality toner image. 30 Am²If it is less than / kg, the magnetic binding force also decreases, so that carrier adhesion tends to occur.
[0071]
In the production method according to the present invention, among the members constituting the polymerization / distillation apparatus, those having a portion exposed to the gas phase portion in the polymerization / distillation vessel include the inner wall of the vessel, the stirrer shaft, the baffle plate, and the raw material inlet. Nozzles such as, various sensors and protective tubes thereof. As materials of these members, those usually used such as stainless steel, glass and FRP can be used. In addition, these surfaces may be subjected to treatments such as electropolishing, Teflon coating, and glass lining.
[0072]
There are various spray patterns in the spray nozzle, and general spray nozzles, hollow cone sprays, flat sprays and the like can be used in the present invention. FIG. 1 shows the spray pattern of a full cone spray, creating a circular pattern with respect to a plane perpendicular to the spray axis. FIG. 2 shows a hollow cone spray, and the spray pattern is annular. FIG. 3 shows a spray pattern of a flat spray, and the spray pattern has a shape like a convex lens cross section.
[0073]
A suitable spray is selected depending on the configuration of the apparatus, and a plurality of sprays can be combined according to the size and shape of the object. For example, a full cone spray or a hollow cone spray having a wide spray area on the vessel wall, or a plurality of flat sprays arranged on the circumference, and a flat spray is used for the stirrer shaft and baffle plate.
[0074]
The relationship between the spray pressure and the flow rate varies greatly depending on the type of spray, but the spray impact force per unit area on the target surface of the spray nozzle is 2.0 to 1.1 × 10.^ThreeDesirably, it is within the range of Pa, and the spray pressure and flow rate are adjusted to achieve spray impact forces within this range. When the spray impact force is less than 2.0 Pa, the cleaning power against the scale-like deposit is not sufficient, and 1.1 × 10^ThreeWhen the pressure is larger than Pa, the spray is too strong, so that the suspension or foam is scattered, which leads to enlargement of the scale adhesion region. Further, a more suitable range can be selected from the above range depending on the type of spray. For example, full cone spray is 2.0 to 15.7 Pa, and hollow cone spray is 1.0 × 10.²~ 7.6 × 10²Pa, 1.0 × 10 for flat spray²~ 1.1 × 10^ThreeIt is preferable to select a range of Pa.
[0075]
The spray angle is appropriately selected depending on the type of spray and the size and shape of the object, but is preferably set in the range of 15 ° to 120 °. When the spray angle is less than 15 °, the range in which water or hot water is sprayed is too small, and it is not preferable because a large number of sprays need to be installed to cover the required area. Further, when the spray angle is larger than 120 °, the spray impact force becomes extremely small and the cleaning power becomes insufficient, which is also not preferable.
[0076]
It is desirable that water or hot water be continuously sprayed throughout the polymerization and distillation operations. However, it is appropriate if you do not want to increase the liquid volume for the convenience of the equipment volume and operating conditions. It may be sprayed intermittently at any frequency.
[0077]
The temperature of the sprayed water or warm water is appropriately selected depending on the operating conditions, but is preferably set in the range of 30 ° C. to 90 ° C. during the polymerization. When the water temperature is lower than 30 ° C., the suspension temperature is lowered. When the water temperature is higher than 90 ° C., the temperature of the target surface is increased, and fusion of the suspended polymer fine particles may occur. During the distillation operation, the temperature is preferably the same as the suspension temperature from the viewpoint of thermal efficiency.
[0078]
In the polymerization apparatus according to the present invention, a stirring blade can be used as a liquid stirring means. The stirring blade used here is not particularly limited as long as the suspension is stirred without stagnation, and a general stirring blade such as a paddle blade, a turbine blade, an anchor blade, or a commercially available full zone blade (SHINKO Pantech). Co., Ltd.), Max Blend Tsubasa (Sumitomo Heavy Industries Co., Ltd.), etc. Among these, a full zone blade and a max blend blade are preferable from the viewpoint of stirring efficiency, and a full zone blade is particularly preferably used.
[0079]
In the distillation apparatus according to the present invention, a stirrer can be used from the viewpoint of distillation efficiency. In this case, the same stirring blade as that used in the polymerization apparatus is selected.
[0080]
A preferred embodiment of the polymerization apparatus used in the present invention will be described with reference to the drawings.
[0081]
FIG. 4 shows an embodiment of the polymerization apparatus according to the present invention. The polymerization apparatus includes a polymerization vessel 1, a stirrer shaft 2, a stirrer blade 3, a stirrer motor 4, a heating jacket 5, a raw material inlet 6, a full cone or hollow cone type spray 7 for cleaning the wall surface, and a flat type spray for the stirrer shaft. 8. It has a liquid discharge port 9. Reference numeral 10 indicates the liquid level of the suspension.
[0082]
5 and 6 show another embodiment of the polymerization apparatus according to the present invention, which shows an elevational view and a plan view, respectively. In both figures, the same reference numerals indicate the same members. This polymerization apparatus is arranged at equal intervals in a polymerization vessel 11, a stirrer shaft 12, a stirring blade 13, a stirring motor 14, a heating jacket 15, a raw material inlet 16, a ring-shaped cleaning water conduit 17, and a wall cleaning unit 17. It has a flat type spray 18, a flat type spray 19 for an agitator shaft, and a liquid discharge port 20. Reference numeral 21 indicates the liquid level of the suspension.
[0083]
Next, the preferable one aspect | mode of the distillation apparatus used for this invention is demonstrated using FIG. The distillation apparatus includes a distillation vessel 31, a stirrer shaft 32, a stirrer blade 33, a stirrer motor 34, a heating jacket 35, a raw material inlet 36, a full cone or hollow cone type spray 37 for cleaning the wall surface, and a flat type spray for the stirrer shaft. 38 and a liquid discharge port 39. Reference numeral 40 designates a distillate outlet, and if necessary, a condenser is connected to condense the distillate. Moreover, when the pressure reduction in a container is required, the extraction port 40 of a fraction can be connected to pressure reduction apparatuses, such as a vacuum pump. Reference numeral 41 indicates the liquid level of the suspension.
[0084]
8 and 9 show another embodiment of the distillation apparatus according to the present invention, and represent an elevation view and a plan view, respectively. In both figures, the same reference numerals indicate the same members. This distillation apparatus is arranged at regular intervals in a distillation vessel 51, a stirrer shaft 52, a stirring blade 53, a stirring motor 54, a heating jacket 55, a raw material inlet 56, a ring-shaped cleaning water conduit 57, and a wall cleaning 57. It has a flat type spray 58, a flat type spray 59 for an agitator shaft, and a liquid discharge port 60. Reference numeral 61 designates a distillate outlet, and if necessary, a condenser is connected to condense the distillate. Moreover, when the pressure reduction in a container is required, the taking-out opening 61 of a fraction can be connected to pressure reduction apparatuses, such as a vacuum pump. Reference numeral 62 indicates the liquid level of the suspension.
[0085]
【Example】
EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention concretely, this invention is not limited at all by these.
[0086]
Each measurement method used in the present invention will be described below.
[0087]
(1) Measurement of particle size distribution and volume average particle size
0.1 to 5 ml of alkylbenzene sulfonate as a surfactant was added to 100 to 150 ml of 1% aqueous sodium chloride solution, and 0.5 to 50 mg of a measurement sample was further added. This solution was subjected to dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and then a particle size distribution of 2 to 40 μm particles was measured using a 100 μm aperture with a Coulter Multisizer (manufactured by Coulter Inc.). Distribution and number average distribution were obtained, and volume average particle diameter was obtained from this.
[0088]
(2) Image quality
The obtained toner particles have a specific surface area of 200 m by the BET method.²/ G of hydrophobic silica was externally added to 0.7 mass%. A ferrite carrier coated with an acrylic resin was mixed so that the externally added toner was 8% by mass to obtain a two-component developer. Under an environment in which this developer is not varied, an image endurance test by continuous paper passing was performed using a modified machine of Canon full-color copying machine CLC700, and fluctuations in image density, unevenness, and the like were visually evaluated.
[0089]
(3) Measurement of fog
The fog was measured using a REFECTOMETER MODEL TC-6DS (manufactured by Tokyo Denshoku Co., Ltd.) and calculated from the following formula. Smaller values indicate less fog.
[0090]
Fog (reflectance) (%) = reflectance of standard paper (%) − reflectance of non-image part of sample (%)
[0091]
(4) Measurement of toner triboelectric charge
Regarding the triboelectric charge amount of the toner, the triboelectric charge amount was measured in the following manner based on the blow-off method after the toner and the carrier were left for a day and night in an environment where there was no fluctuation.
[0092]
FIG. 10 is an explanatory diagram of an apparatus for measuring the triboelectric charge amount of toner. First, in a metal measuring container 72 having a 500 mesh screen 73 at the bottom, a mixture of toner and carrier mass ratio 8:92 to be measured for triboelectric charge is put into a polyethylene bottle having a capacity of 50 to 100 ml, Shake by hand 200 times, put about 0.2 g of the mixture (developer) and make a metal lid 74. Weigh the entire measurement container 72 at this time,₁(G). Next, in the suction machine 71 (at least a part in contact with the measurement container 72 is suctioned), the pressure of the vacuum gauge 75 is set to 2450 Pa by suctioning from the suction port 77 and adjusting the air volume control valve 76. In this state, suction is performed for 2 minutes to remove the toner by suction. The maximum value of the potential indicated by the electrometer 79 at this time is V (volt). Here, 78 is a capacitor, and the capacity is C (μF). Also, weigh the entire measurement container after suction.₂(G). The triboelectric charge amount (mC / kg) of the toner is calculated as follows:
[0093]
Frictional charge (mC / kg) = C x V / (W₁-W₂)
[0094]
(5) Presence rate of irregular shaped toner
The toner was observed using a scanning electron microscope, and the abundance of the irregular shaped toner was calculated. The abundance (%) of the amorphous toner is calculated as follows.
[0095]
Amorphous toner abundance ratio (%) = number of irregular toners / total number of toners × 100
[0096]
Example 1
An aqueous dispersion medium and a polymerizable monomer composition were prepared as follows.
[0097]
(Preparation of aqueous dispersion medium)
The following components were mixed in a container with an internal volume of 160 liters, heated to 60 ° C., and then rotated at 3700 rpm with a high-speed rotary shear stirrer CLEARMIX (M Technique Co., Ltd.). Stir.
・ 98.4 parts by mass of water
・ Na_ThreePO_Four                                              1.0 part by weight
[0098]
Next, the inside of the container is purged with nitrogen, and CaCl is added thereto.₂0.6 mass parts is added and reacted, Ca_Three(PO_Four)₂An aqueous dispersion medium containing fine particles was obtained.
[0099]
(Preparation of polymerizable monomer composition)
・ Styrene monomer 63.9 parts by mass
-N-butyl acrylate monomer 13.1 parts by mass
・ 6.2 parts by weight of quinacridone pigment
-3.9 parts by mass of terephthalic acid-propylene oxide modified bisphenol A
・ Divinyl benzene 0.2 parts by mass
-0.8 mass part of di-tert-butylsalicylic acid aluminum compound
・ Ester wax (release agent No. 5) 9.6 parts by mass
Among the components described above, a part of the styrene monomer, a quinacridone pigment, and an aluminum di-tert-butylsalicylate compound were mixed and dispersed for 5 hours using a handy mill (Mitsui Mining Co., Ltd.). The remainder of the polymer and other compositions were added and heated to 60 ° C. and mixed until fully compatible. Thereafter, 2.3 parts by mass of 2,2′-azobis (2,4-dimethylvaleronitrile) as a polymerization initiator was added thereto to obtain a polymerizable monomer composition.
[0100]
The polymerizable monomer composition prepared above was put into the aqueous dispersion medium prepared above, and the number of revolutions of CLEARMIX was 3700 rpm and stirred for 10 minutes for granulation.
[0101]
(Polymerization process)
The suspension granulated in the above process is introduced into the polymerization apparatus shown in FIG. 4 (the spray for the container wall is a full cone type), and polymerization is performed at a rotation speed of the stirring blade of 100 revolutions / minute and a liquid temperature of 60 ° C. It was. After 5 hours, the polymerization temperature was raised to 80 ° C., and heating and stirring were further continued for 3 hours to complete the polymerization. During the polymerization process, warm water at 60 ° C. was sprayed intermittently at a frequency of 3 seconds per 5 minutes by spraying on the wall of the vessel and spraying on the stirrer shaft. Other spray conditions are shown in Table 1.
[0102]
[Table 1]

[0103]
(Evaluation of toner and adhesion status)
After the temperature of the suspension in the polymerization apparatus has dropped, the suspension is discharged from the polymerization apparatus, to which is added dilute hydrochloric acid to dissolve the dispersant fixed to the toner particle surface, and after solid-liquid separation, water washing, filtration, Polymerized toner particles were obtained by drying. The abundance of the irregular toner was 0.2%. When the particle size distribution of the toner particles was measured, the volume average particle size was 7.5 μm, the particle size distribution was sharp, and the triboelectric charge amount was as high as −41 (μC / g). Further, when the inside of the polymerization container after discharging the suspension was examined, 33.1 g of a scale-like deposit was generated on the wall surface and the surface of the stirrer shaft, but the toner was repeatedly removed without removing the deposit. Even if it was manufactured, it was at a level where there was no problem.
[0104]
Next, hydrophobic silica was externally added to the obtained toner particles, and a ferrite carrier coated with an acrylic resin was mixed to obtain a two-component developer. When a 20000 sheet image was tested, the fog was 0.2%, and the image density was not changed or uneven throughout, and a clear and stable image having excellent fixability was stably obtained.
[0105]
Example 2
A toner was obtained in exactly the same manner as in Example 1 except that the spray angle and spray impact force were set as shown in Table 2. The abundance of the irregular toner was 0.2%. When the particle size distribution of the toner particles was measured, the volume average particle size was 7.4 μm and the particle size distribution was almost the same as in Example 1. The triboelectric charge amount was −39 (μC / g). The amount of scale-like deposits was 34.0 g in terms of dry mass, and even if the toner was repeatedly manufactured without removing the deposits, it was at a level with no problem.
[0106]
Next, when 20000 prints were tested in the same manner as in Example 1, the fog was 0.3%, there was no fluctuation or unevenness in the image density from start to finish, and a clear and excellent fixability image was stabilized. Obtained.
[0107]
[Table 2]

[0108]
Comparative Example 1
A toner was obtained in exactly the same manner as in Example 1 except that the agitator shaft spray was not used. The abundance of the irregular toner was 2.5%. When the particle size distribution of the toner particles was measured, the volume average particle size was 7.7 μm and the particle size distribution was almost the same as in Example 1. The triboelectric charge amount was −33 (μC / g). The amount of scale deposits was 91.3 g in total in terms of dry mass, and was partially peeled off and could not be repeatedly manufactured without removing the deposits.
[0109]
Next, when 20000 sheets were printed out in the same manner as in Example 1, the fog was 1.1%, and the image density was not fluctuated or uneven at the beginning, and a stable image was obtained. White streaks and unevenness occurred.
[0110]
Comparative Example 2
A toner was obtained in exactly the same manner as in Example 1 except that the spray angle and spray impact force were set as shown in Table 3. The abundance of the irregular toner was 3.4%. When the particle size distribution of the toner particles was measured, the volume average particle size was 7.8 μm, and the particle size distribution was almost the same as in Example 1. The triboelectric charge amount was −30 (μC / g). The amount of scale-like deposits was 120.8 g in total in terms of dry mass, and was partially peeled off and could not be repeatedly manufactured unless the deposits were removed.
[0111]
Next, when 20000 prints were tested in the same manner as in Example 1, fog was 1.2%, and white streaks and unevenness occurred earlier than Comparative Example 1.
[0112]
[Table 3]

[0113]
Example 3
After the polymerization process was carried out in exactly the same manner as in Example 1, the suspension was discharged from the polymerization apparatus, and this was introduced into the distillation apparatus shown in FIG. 8, where the number of revolutions of the stirring blade was 100 revolutions / minute and the liquid temperature was 80. Distillation was performed at 0 ° C. and a distillation vessel internal pressure of 49.3 kPa (absolute pressure). During the distillation process, hot water at 80 ° C. was sprayed intermittently at a frequency of 2 seconds per 2 minutes by spraying on the wall of the vessel and spraying on the stirrer shaft. Table 4 shows other spray conditions.
[0114]
[Table 4]

[0115]
When the toner was evaluated after the distillation step, the abundance of the irregular shaped toner was 0.3%. When the particle size distribution of the toner particles was measured, the volume average particle size was 7.6 μm and the particle size distribution was almost the same as in Example 1. The triboelectric charge amount was −42 (μC / g). The amount of the scale-like deposits was 35.2 g in terms of dry mass, and even if the toner was repeatedly manufactured without removing the deposits, it was at a level with no problem.
[0116]
Next, when 20000 printout tests were performed in the same manner as in Example 1, the fog was 0.5%, there was no fluctuation or unevenness in the image density from start to finish, and a clear and excellent fixability image was stabilized. Obtained.
[0117]
Example 4
A toner was obtained in exactly the same manner as in Example 3 except that the spray angle and spray impact force were set as shown in Table 5. The abundance of the irregular toner was 0.2%. When the particle size distribution of the toner particles was measured, the volume average particle size was 7.2 μm and the particle size distribution was almost the same as in Example 1. The triboelectric charge amount was −44 (μC / g). The amount of the scale-like deposits was 31.9 g in terms of dry mass, and even if the toner was repeatedly manufactured without removing the deposits, it was at a level with no problem.
[0118]
Next, when 20000 prints were tested in the same manner as in Example 1, the fog was 0.4%, there was no fluctuation or unevenness in the image density from beginning to end, and a clear and excellent fixability image was stabilized. Obtained.
[0119]
[Table 5]

[0120]
Comparative Example 3
The spray impact force of the stirrer spray during the distillation process is 1.7 × 10^ThreeExcept for Pa, a toner was obtained in the same manner as in Example 3. The abundance of the irregular toner was 5.9%. When the particle size distribution of the toner particles was measured, the volume average particle size was 7.6 μm and the particle size distribution was almost the same as in Example 1. The triboelectric charge amount was −33 (μC / g). The amount of scale-like deposits was 102.4 g in total in terms of dry mass, and adhesion near the top of the distillation vessel that was not normally observed was observed. This is thought to be because the spray impact force of the spray for the stirrer shaft was too great and the suspension splashed. In addition, the scale-like deposits were partly peeled off and could not be repeatedly manufactured without removing the deposits.
[0121]
Next, when 20000 printout tests were performed in the same manner as in Example 1, the fog was 1.7% and a stable image was obtained in the initial stage. Unevenness occurred. Further, slight filming was observed on the photoreceptor.
[0122]
【The invention's effect】
According to the present invention, in the toner production process by the suspension polymerization method, a scale-like deposit is generated on a portion of the member constituting the polymerization / distillation apparatus exposed to the gas phase portion of the polymerization / distillation vessel. Can be suppressed. When the adhering material is peeled off and mixed with a spherical toner having a regular particle size, it becomes an irregular toner, and the performance of the toner is deteriorated. However, according to the present invention, the generation of the adhering material is remarkably reduced. Therefore, it is possible to obtain a toner in which the removal operation is essentially unnecessary, and when image formation is performed, there is no fluctuation or unevenness in the image density, and a stable and clear image with excellent fixability can be obtained. .
[Brief description of the drawings]
FIG. 1 is a diagram showing a spray pattern of a full cone spray.
FIG. 2 is a diagram showing a spray pattern of a hollow cone spray.
FIG. 3 is a diagram showing a spray pattern of flat spray.
FIG. 4 is a schematic view showing an embodiment of a polymerization apparatus according to the present invention.
FIG. 5 is a schematic view showing another embodiment of the polymerization apparatus according to the present invention.
FIG. 6 is a schematic view showing another embodiment of the polymerization apparatus according to the present invention.
FIG. 7 is a schematic view showing an embodiment of a distillation apparatus according to the present invention.
FIG. 8 is a schematic view showing another embodiment of the distillation apparatus according to the present invention.
FIG. 9 is a schematic view showing another embodiment of the distillation apparatus according to the present invention.
FIG. 10 is an explanatory diagram of an apparatus for measuring the triboelectric charge amount of toner.
[Explanation of symbols]
1 Polymerization vessel
2,22 Agitator shaft
3,23 stirring blade
4,26 Stirring motor
5,25 Heating jacket
6,27 Raw material inlet
7 Full cone or hollow cone type spray
8 Flat type spray
9 Liquid outlet
10 Liquid level of suspension
31 Distillation vessel

Claims (2)

In a method for producing a polymerization toner obtained by dispersing and polymerizing a polymerizable monomer composition containing at least a polymerizable monomer and a colorant in an aqueous dispersion medium,
During the polymerization operation, each of the components constituting the polymerization vessel inner wall gas phase portion and the polymerization apparatus exposed to the gas phase portion in the polymerization vessel is sprayed with a dedicated spray nozzle, and water or hot water is applied to the target surface. A method for producing a toner, characterized by spraying so that a spray impact force per unit area is 2.0 to 1.1 × 10 ³ Pa. A step of dispersing a polymerizable monomer composition containing at least a polymerizable monomer and a colorant in an aqueous dispersion medium and polymerizing, and subsequently removing unreacted polymerizable monomer from the system by distillation operation. In the production method of the polymerization toner obtained through
During the polymerization operation and the distillation operation, each of the components constituting the inner wall of each vessel and the portion constituting the polymerization device and the distillation device is exposed to the gas phase in each vessel using a dedicated spray nozzle, A method for producing a toner, characterized by spraying hot water so that a spray impact force per unit area on a target surface is 2.0 to 1.1 × 10 ³ Pa.

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