JP2004077577A - Toner for noncontact fixation - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a toner for noncontact fixation having excellent fixability and giving a high quality image free of a void. <P>SOLUTION: The toner for noncontact fixation contains an amorphous polyester having a softening point to maximum peak temperature of heat of fusion (softening point/peak temperature) ratio of >1.3 to 4.0 and a crystalline polyester having a softening point to maximum peak temperature of heat of fusion(softening point/peak temperature) ratio of 0.6-1.3 as binder resins, wherein the softening point of the crystalline polyester is 60-150°C and the content of a water-soluble component in any of the crystalline polyester and the amorphous polyester is adjusted to ≤3 mg/g expressed in terms of carbon. <P>COPYRIGHT: (C)2004,JPO

Description

【００１１】
（式中、Ｒは炭素数２又は３のアルキレン基、ｘ及びｙは正の数を示し、ｘとｙの和は１〜１６、好ましくは１．５〜５．０である）
で表されるビスフェノールＡのアルキレンオキサイド付加物、水素添加ビスフェノールＡ、及びそれらのアルキレン（炭素数２〜４）オキサイド（平均付加モル数１〜１６）付加物等が挙げられ、ビスフェノールＡのアルキレンオキサイド付加物がより有効である。
【００１２】
結晶性ポリエステルの製造に好ましく用いられるアルコール成分としては、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、１，５−ペンタンジオール、１，６−ヘキサンジオール、ネオペンチルグリコール、１，４−ブテンジオール等の炭素数２〜６の脂肪族ジオールが挙げられ、これらの中では、α，ω−直鎖アルカンジオール、特に１，４−ブタンジオールがより有効である。
【００１３】
また、非晶質ポリエステルの製造に好ましく用いられるカルボン酸成分としては、ドデセニルコハク酸、オクテニルコハク酸等の炭素数１〜２０のアルキル基又は炭素数２〜２０のアルケニル基で置換されたコハク酸、それらの酸の無水物及びそれらの酸のアルキル（炭素数１〜３）エステル等が挙げられ、これらの中では、アルキル基又はアルケニル基で置換されたコハク酸がより有効である。
【００１４】
結晶性ポリエステルの製造に好ましく用いられるカルボン酸成分としては、シュウ酸、マロン酸、マレイン酸、フマル酸、シトラコン酸、イタコン酸、グルタコン酸、コハク酸、アジピン酸、及びこれらの酸の無水物、アルキル（炭素数１〜３）エステル等の炭素数２〜８の脂肪族ジカルボン酸化合物が挙げられ、これらの中では、フマル酸及びアジピン酸、特にフマル酸がより有効である。なお、脂肪族ジカルボン化合物とは、前記の如く、脂肪族ジカルボン酸、その無水物及びそのアルキル（炭素数１〜３）エステルを指すが、これらの中では、脂肪族ジカルボン酸が好ましい。
【００１５】
なお、アルコール成分及びカルボン酸成分には、得られる樹脂の分子量や軟化点の調整を目的として、１価のアルコール及びカルボン酸化合物がさらに含有されていてもよい。
【００１６】
以上より、非晶質ポリエステルとしては、
▲１▼　炭素数２〜６の脂肪族ジオール、炭素数２〜８の脂肪族カルボン酸化合物等の結晶化を促進するモノマーが用いられる場合は、これらのモノマーを２種以上併用して結晶化が抑制された樹脂、即ちアルコール成分及びカルボン酸成分のいずれにおいても、これらのモノマーの１種が各成分中１０〜７０モル％、好ましくは２０〜６０モル％を占め、かつこれらのモノマーが２種以上、好ましくは２〜４種用いられた樹脂、又は
▲２▼　非結晶化を促進するモノマー、好ましくはアルコール成分として、式（Ｉ）で表されるビスフェノールＡのアルキレンオキサイド付加物が、又はカルボン酸成分としてアルキル基もしくはアルケニル基で置換されたコハク酸が、アルコール成分中又はカルボン酸成分中、好ましくは両成分のそれぞれにおいて３０〜１００モル％、好ましくは５０〜１００モル％、特に好ましくは１００モル％含有されている樹脂が好ましい。特に▲２▼の樹脂は、その製造の際に特にビスフェノールＡのアルキレンオキサイド付加物を用いることにより、水溶解性成分の含有量を容易に低減させることができ、好ましい。
【００１７】
本発明において、非晶質ポリエステルの軟化点は、定着性及び保存性の観点から、７０〜１６０℃が好ましく、９０〜１５０℃がより好ましい。
【００１８】
非晶質ポリエステルのガラス転移点は、定着性及び保存性の観点から、５０〜８０℃が好ましく、５５〜７５℃がより好ましい。なお、ガラス転移点は非晶質樹脂に特有の物性であり、融解熱の最大ピーク温度とは区別される。
【００１９】
なお、非晶質ポリエステルが２種以上のポリエステルからなる場合は、その少なくとも１種、好ましくはそのいずれもが以上に説明した物性を有する非晶質ポリエステルであるのが望ましい。特に、定着性と着色剤や離型剤の分散性の観点から、軟化点が７０℃以上、１２０℃未満の低軟化点ポリエステルと軟化点が１２０℃以上、１６０℃以下の高軟化点ポリエステルとが、好ましくは２０／８０〜８０／２０の重量比（低軟化点ポリエステル／高軟化点ポリエステル）で併用されているのが好ましい。
【００２０】
非晶質ポリエステルにおける水溶解性成分の含有量は、吸湿性及び水や水溶解性成分自身によるボイドの発生を防止するために、炭素量で、３ｍｇ／ｇ以下であり、好ましくは１ｍｇ／ｇ以下、より好ましくは０．１ｍｇ／ｇ以下である。
水溶解性成分の含有量は、原料モノマーにおける水溶解性化合物、特には低分子量化合物の含有量や反応率、反応手順、反応終了後の減圧トッピング等の方法により、調整することができる。
【００２１】
一方、結晶性ポリエステルとしては、アルコール成分と炭素数が２〜８、好ましくは４〜６、より好ましくは４の脂肪族ジカルボン酸化合物を６０モル％以上含有したカルボン酸成分を縮重合させて得られた樹脂が好ましい。
【００２２】
炭素数２〜８の脂肪族ジカルボン酸化合物は、カルボン酸成分中に、６０モル％以上、好ましくは８０〜１００モル％、より好ましくは９０〜１００モル％含有されているのが望ましい。特に、その中の１種の脂肪族ジカルボン酸化合物が、カルボン酸成分中の６０モル％以上、好ましくは７０〜１００モル％、より好ましくは８０〜１００モル％を占めているのが望ましい。なかでも、フマル酸が、カルボン酸成分中、好ましくは６０モル％以上、より好ましくは７０〜１００モル％、特に好ましくは８０〜１００モル％含有されているのが望ましい。
【００２３】
また、アルコール成分には、炭素数が２〜６、好ましくは４〜６の脂肪族ジオールが含有されているのが好ましい。炭素数２〜６の脂肪族ジオールは、アルコール成分中に、６０モル％以上、好ましくは８０〜１００モル％、より好ましくは９０〜１００モル％含有されているのが望ましい。特に、その中の１種の脂肪族ジオールが、アルコール成分中の７０モル％以上、好ましくは８０〜９５モル％を占めているのが望ましい。なかでも、１，４−ブタンジオールが、アルコール成分中、好ましくは６０モル％以上、より好ましくは７０〜１００モル％、特に好ましくは８０〜１００モル％含有されているのが望ましい。
【００２４】
本発明において、結晶性ポリエステルの軟化点は、定着性の観点から、６０〜１５０℃であり、好ましくは７０〜１４０℃、より好ましくは８０〜１３０℃である。
【００２５】
結晶性ポリエステルの水溶解性成分の含有量は、定着性を維持しつつボイドの発生を防止するために、炭素量で、３ｍｇ／ｇ以下であり、好ましくは０．５〜３ｍｇ／ｇ、より好ましくは１〜２ｍｇ／ｇである。水溶解性成分の含有量は、非晶質ポリエステルと同様にして調整することができるが、結晶性ポリエステルの場合は、例えば、炭素数２〜６、好ましくは炭素数２〜４の脂肪族ジオールの含有量や反応率、カルボン酸成分に対するモル比を調整する方法が有効である。
【００２６】
非晶質ポリエステル及び結晶性ポリエステルは、いずれも、アルコール成分とカルボン酸成分とを、例えば、不活性ガス雰囲気中にて、要すればエステル化触媒、重合禁止剤等を用いて、１２０〜２３０℃の温度で反応させることにより、縮重合させて得られる。具体的には、樹脂の強度を上げるために全単量体を一括仕込みしたり、ポリエステルの分子量を高める手段として、重合の後半に反応系を減圧、例えば１０ｋＰａ以下にすることにより、反応を促進させる方法も有効である。
【００２７】
本発明において、非晶質ポリエステルは、結晶性ポリエステルの分散性を高めるために、結着樹脂の主成分として含有されているのが好ましい。非晶質ポリエステルの含有量は、結着樹脂中、５０〜９９重量％が好ましく、より好ましくは５０〜９５重量％、特に好ましくは７０〜９０重量％である。
【００２８】
非晶質ポリエステルの結晶性ポリエステルに対する重量比（非晶質ポリエステル／結晶性ポリエステル）は、５０／５０〜９９／１が好ましく、５０／５０〜９５／５がより好ましく、７０／３０〜９０／１０が特に好ましい。
【００２９】
結着樹脂としては、本発明の効果を損なわない範囲で、非晶質ポリエステルポリアミド、スチレン−アクリル樹脂等のビニル系樹脂、２種以上の樹脂成分が部分的に化学結合したハイブリッド樹脂等が適宜配合されていてもよい。
【００３０】
本発明のトナーには、さらに、着色剤、荷電制御剤、離型剤、導電性調整剤、体質顔料、繊維状成分等の補強充填剤、酸化防止剤、老化防止剤、流動性向上剤、クリーニング性向上剤等の添加剤が、適宜含有されていてもよい。
【００３１】
着色剤としては、トナー用着色剤として用いられている染料、顔料等のすべてを使用することができ、カーボンブラック、フタロシアニンブルー、パーマネントブラウンＦＧ、ブリリアントファーストスカーレット、ピグメントグリーンＢ、ローダミン−Ｂベース、ソルベントレッド４９、ソルベントレッド１４６　、ソルベントブルー３５、キナクリドン、カーミン６Ｂ、ジスアゾエロー等が挙げられ、これらは単独で又は２種以上を混合して用いることができ、本発明のトナーは、黒トナー、カラートナー、フルカラートナーのいずれにも使用することができる。着色剤の含有量は、結着樹脂１００重量部に対して、１〜４０重量部が好ましく、３〜１０重量部がより好ましい。
【００３２】
荷電制御剤としては、ニグロシン染料、３級アミンを側鎖として含有するトリフェニルメタン系染料、４級アンモニウム塩化合物、ポリアミン樹脂、イミダゾール誘導体等の正帯電性荷電制御剤及び含金属アゾ染料、銅フタロシアニン染料、サリチル酸のアルキル誘導体の金属錯体、ベンジル酸のホウ素錯体等の負帯電性荷電制御剤が挙げられる。
【００３３】
離型剤としては、カルナウバワックス、ライスワックス等の天然エステル系ワックス、ポリプロピレンワックス、ポリエチレンワックス、フィッシャートロプッシュ等の合成ワックス、モンタンワックス等の石炭系ワックス、アルコール系ワックス等のワックスが挙げられ、これらは単独でまたは２種以上を混合して含有されていてもよい。一般に、優れた低温定着性を得るためには、カルナウバワックス等の比較的融点の低いワックスが併用されることが好ましい。
【００３４】
本発明のトナーは、混練粉砕法、乳化転相法、重合法等の従来より公知のいずれの方法により得られたものであってもよいが、製造が容易であり、本発明の効果が顕著に発揮されることから、混練粉砕法により得られた粉砕トナーが好ましい。なお、混練粉砕法によりトナーを得る場合、結着樹脂、着色剤等をヘンシェルミキサー等の混合機で均一に混合した後、密閉式ニーダー又は１軸もしくは２軸の押出機等で溶融混練し、冷却、粉砕、分級して製造することができ、乳化転相法では、結着樹脂、着色剤等を有機溶剤に溶解又は分散後、水を添加する等によりエマルジョン化し、次いで分離、分級して製造することができる。さらに、トナーの表面には、必要に応じて疎水性シリカ等の流動性向上剤等が外添されていてもよい。トナーの体積平均粒径は、３〜１５μｍが好ましい。
【００３５】
本発明のトナーは、磁性体微粉末を含有するときは単独で現像剤として、また磁性体微粉末を含有しないときは非磁性一成分系現像剤として、もしくはキャリアと混合して二成分系現像剤として使用することができる。
【００３６】
本発明のトナーは、非接触定着における定着性に極めて優れたおり、非接触定着に特有の課題であるボイドの発生も防止することができる。特に、輻射加熱をフラッシュ的に行うフラッシュ定着用トナーとして好適に用いることができる。
フラッシュ定着では、例えばキセノン、ネオン、アルゴン、クリプトンランプ等の発光強度の高い光をトナー像に０．１〜３ミリ秒照射し、０．５〜５ジュール／ｃｍ^２程度の熱量を与えて、トナー像を溶融定着させることが好ましい。
【００３７】
【実施例】
〔軟化点〕
高化式フローテスター（（株）島津製作所製、ＣＦＴ−５００Ｄ）を用い、１ｇの試料を昇温速度６℃／分で加熱しながら、プランジャーにより１．９６ＭＰａの荷重を与え、直径１ｍｍ、長さ１ｍｍのノズルを押し出すようにし、これによりフローテスターのプランジャー降下量（流れ値）−温度曲線を描き、そのＳ字曲線の高さをｈとするときｈ／２に対応する温度（樹脂の半分が流出した温度）を軟化点とする。
【００３８】
〔融解熱の最大ピーク温度及びガラス転移点〕
示差走査熱量計（セイコー電子工業社製、ＤＳＣ２１０）を用いて２００℃まで昇温し、その温度から降温速度１０℃／分で０℃まで冷却したサンプルを昇温速度１０℃／分で測定し、融解熱の最大ピーク温度を求める。また、ガラス転移点は、前記測定で最大ピーク温度以下のベースラインの延長線とピークの立ち上がり部分から、ピークの頂点まで、最大傾斜を示す接線との交点の温度であり、非晶質樹脂に特有の物性である。
【００３９】
〔水溶解性成分の含有量〕
目開き１ｍｍの篩は通過するが目開き７５０μｍの篩は通過しない試料２．５ｇを純水２５０ｍｌと混合し、２０℃で２４時間振とうする。試料と水との混合液を孔径０．２μｍのメンブランフィルターでろ過した後、ろ液中の炭素濃度（ｐｐｍ）を炭素量測定装置「ＥＭＩＡ−１１０」（ＨＯＲＩＢＡ社製）により測定し、次式：
【００４０】
【数１】

【００４１】
により、水溶解性成分の含有量を算出する。
【００４２】
結晶性ポリエステルの製造例
表１に示す原料モノマー、ハイドロキノン２ｇ及び酸化ジブチル錫４ｇを窒素雰囲気下、１６０℃で５時間かけて反応させた後、２００℃に昇温して１時間反応させた。さらに８．３ｋＰａにて所望の軟化点が得られるまで反応させて、樹脂ａ〜ｅを得た。
【００４３】
【表１】

【００４４】
非晶質ポリエステルの製造例
表２に示す無水トリメリット酸以外の原料モノマー及び酸化ジブチル錫４ｇを窒素雰囲気下、２２０℃で８時間かけて反応させた後、さらに８．３ｋＰａにて１時間反応させた。さらに、２１０℃で無水トリメリット酸を反応系に添加し、所望の軟化点に達するまで反応させて、樹脂Ａ、Ｂを得た。
【００４５】
【表２】

【００４６】
実施例１、３〜５、比較例１、２
表３に示す結着樹脂１００重量部、カーボンブラック「ＭＯＧＵＬ　Ｌ」（キャボット社製）４重量部、荷電制御剤「Ｔ−７７」（保土谷化学工業社製）１重量部、及びカルナバワックス「カルナバワックスＣ１」（加藤洋行社製）１重量部をヘンシェルミキサーで十分に混合した後、同方向回転二軸押出機（混練部分の全長：１５６０ｍｍ、スクリュー径：４２ｍｍ、バレル内径：４３ｍｍ）を用い、ロール回転速度を２００回転／分、ロール内の加熱温度を１００℃、混合物の供給速度を１０ｋｇ／時に調整して溶融混練した。混合物の平均滞留時間は約１８秒であった。得られた溶融混練物を、冷却、粗粉砕した後、ジェットミルにより粉砕し分級して、体積平均粒子径が８．０μｍの粉体を得た。得られた粉体１００重量部に、外添剤として「アエロジル　Ｒ−９７２」（日本アエロジル（株）製）１．０重量部を添加し、ヘンシェルミキサーで混合することにより、トナーを得た。
【００４７】
実施例２
荷電制御剤として「Ｔ−７７」の代わりに「ＬＲ−１４７」（日本カーリット社製）１重量部を、カーボンブラックの代わりに、シアン顔料「ＥＣＢ−３０１」（大日精化社製）４重量部を、それぞれ使用した以外は、実施例１と同様にして、トナーを得た。
【００４８】
試験例１〔定着性の評価〕
トナー４重量部とシリコンコートフェライトキャリア（関東電化工業社製、平均粒子径：９０μｍ）９６重量部とを１０分間ターブラーミキサーにて混合して現像剤を得た。次いで、複写機「ＡＲ−５０５」（シャープ（株）製）に現像剤を実装し、トナー付着量を０．６ｍｇ／ｃｍ^２に調整し、定着紙として「ＣｏｐｙＢｏｎｄ　ＳＦ−７０ＮＡ」（シャープ社製、７５ｇ／ｍ^２）を用いて、２ｃｍ×１２ｃｍの未定着画像を得た。
【００４９】
未定着画像を、閃光ランプとしてキセノンランプを用い、パルス持続時間が１ミリ秒、閃光ランプによるエネルギーが像担持シート表面において３．０ジュール／ｃｍ^２の条件で、フラッシュ定着させた。
【００５０】
得られた定着画像を、５００ｇの荷重をかけた底面が１５ｍｍ×７．５ｍｍの砂消しゴムで５往復擦り、擦る前後の光学反射密度を反射濃度計「ＲＤ−９１５」（マクベス社製）を用いて測定し、両者の比率（擦り後／擦り前）を定着率として求め、以下の評価基準により、定着性を評価した。結果を表３に示す。
【００５１】
〔評価基準〕
定着率が
◎：９０％以上
○：７０％以上９０％未満
×：７０％未満
【００５２】
試験例２〔画質の評価〕
試験例１と同様にして得られた２ｃｍ×１２ｃｍの未定着画像を、閃光ランプによるエネルギーを像担持シート表面において４．０ジュール／ｃｍ^２にした以外は、試験例１と同様にして、フラッシュ定着させた。得られた定着画像におけるボイドの発生による白抜けの有無を目視により観察して、以下の評価基準により、画質を評価した。結果を表３に示す。
【００５３】
〔評価基準〕
○：白抜けはほとんどない。
△：白抜けがやや認められる。
×：白抜けが多い。
【００５４】
【表３】

【００５５】
以上の結果より、実施例のトナーは定着性が良好で、ボイドによる白抜けの少ない高品質な画像が得られているのに対し、水溶解度が高い比較例１のトナーは、定着性に問題はないものの、ボイドが発生しており、結晶性ポリエステルを用いていない比較例２のトナーは、定着性に欠けていることが分かる。
【００５６】
【発明の効果】
本発明により、定着性に優れ、ボイドが発生することなく、高品質の画像が得られる非接触定着用トナーを提供することができる。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a non-contact fixing toner used for developing an electrostatic latent image formed in an electrophotographic method, an electrostatic recording method, an electrostatic printing method, or the like.
[0002]
[Prior art]
Non-contact fixing has the advantage of obtaining high-resolution images because there is no offset phenomenon seen in contact fixing and no toner spreading, but it has poor energy efficiency, poor fixability, voids, etc. Has the disadvantage of
[0003]
As means for solving these problems in non-contact fixing, for example, a toner having a defined softening point and glass transition point (Japanese Patent Application Laid-Open No. 2001-350286), and two or more kinds of toners having a specific structure and different softening points. Toners made of polyester (Japanese Patent Application Laid-Open Nos. 2001-100456 and 2001-100549) and the like have been proposed, and although a certain effect is recognized, further improvement in fixability is desired.
[0004]
A flash fixing toner containing a crystalline polyester and an epoxy resin is also known (JP-A-4-250464). However, such a crystalline polyester has a melting point as low as about 70 ° C. The degree of dispersion is insufficient, the dispersibility in the epoxy resin is poor, and a sufficient effect cannot be obtained.
[0005]
[Problems to be solved by the invention]
SUMMARY OF THE INVENTION It is an object of the present invention to provide a non-contact fixing toner which is excellent in fixing property and in which a high quality image can be obtained without generating voids.
[0006]
[Means for Solving the Problems]
The present invention relates to an amorphous polyester having a ratio of softening point to maximum peak temperature of heat of fusion (softening point / peak temperature) of more than 1.3 and 4.0 or less, and a ratio of softening point to maximum peak temperature of heat of fusion. A non-contact fixing toner containing a crystalline polyester having a softening point / peak temperature of 0.6 to 1.3 as a binder resin, wherein the crystalline polyester has a softening point of 60 to 150 ° C. Wherein the content of the water-soluble component is 3 mg / g or less in terms of carbon in both the crystalline polyester and the amorphous polyester.
[0007]
BEST MODE FOR CARRYING OUT THE INVENTION
The toner of the present invention contains an amorphous polyester and a crystalline polyester as a binder resin. Here, “crystalline” means that the ratio of the softening point to the maximum peak temperature of the heat of fusion (softening point / peak temperature) is 0.6 to 1.3, and the effect of improving the fixability by the crystalline polyester is more. 0.9 to 1.2 is preferable, and 0.95 to 1.1 is more preferable because it is remarkably obtained. The term “amorphous” means that the ratio of the softening point to the maximum peak temperature of the heat of fusion (softening point / peak temperature) is greater than 1.3 and equal to or less than 4.0, preferably 1.5 to 3.0. Say.
[0008]
Both the amorphous polyester and the crystalline polyester can be obtained by polycondensing an alcohol component and a carboxylic acid component, respectively, by appropriately selecting the type of raw material monomers, reaction conditions, and the like. The crystallinity of the polyester can be adjusted.
[0009]
Alcohol components preferably used for the production of amorphous polyester include polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane and polyoxyethylene (2.2) -2,2- Formula (I), such as bis (4-hydroxyphenyl) propane:
[0010]
Embedded image

[0011]
(Wherein, R is an alkylene group having 2 or 3 carbon atoms, x and y are positive numbers, and the sum of x and y is 1 to 16, preferably 1.5 to 5.0)
Alkylene oxide adducts of bisphenol A, hydrogenated bisphenol A, and alkylene (C2-4) oxide (average addition moles 1-16) adducts thereof represented by the formula: Additives are more effective.
[0012]
Alcohol components preferably used in the production of crystalline polyester include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,5-pentanediol and 1,6-hexane. Examples thereof include aliphatic diols having 2 to 6 carbon atoms such as diols, neopentyl glycol, and 1,4-butenediol. Among them, α, ω-linear alkanediols, particularly 1,4-butanediol, are more preferred. It is valid.
[0013]
Further, as the carboxylic acid component preferably used in the production of the amorphous polyester, succinic acid substituted with an alkyl group having 1 to 20 carbon atoms or an alkenyl group having 2 to 20 carbon atoms, such as dodecenyl succinic acid, octenyl succinic acid, etc. Acid anhydrides and alkyl (C1-3) esters of these acids, among which succinic acid substituted with an alkyl group or an alkenyl group is more effective.
[0014]
As the carboxylic acid component preferably used in the production of the crystalline polyester, oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, succinic acid, adipic acid, and anhydrides of these acids, Examples thereof include aliphatic dicarboxylic acid compounds having 2 to 8 carbon atoms such as alkyl (1 to 3 carbon atoms) esters. Of these, fumaric acid and adipic acid, particularly fumaric acid, are more effective. As described above, the aliphatic dicarboxylic compound refers to an aliphatic dicarboxylic acid, an anhydride thereof, and an alkyl (C1 to C3) ester thereof, and among these, an aliphatic dicarboxylic acid is preferable.
[0015]
The alcohol component and the carboxylic acid component may further contain a monohydric alcohol and a carboxylic acid compound for the purpose of adjusting the molecular weight and softening point of the obtained resin.
[0016]
From the above, as amorphous polyester,
{Circle around (1)} When monomers that promote crystallization such as aliphatic diols having 2 to 6 carbon atoms and aliphatic carboxylic acid compounds having 2 to 8 carbon atoms are used, crystallization is performed by using two or more of these monomers in combination. In the resin in which is suppressed, that is, in both the alcohol component and the carboxylic acid component, one of these monomers accounts for 10 to 70 mol%, preferably 20 to 60 mol% of each component, and Or more, preferably 2 to 4 kinds of resins, or (2) a monomer for promoting non-crystallization, preferably an alkylene oxide adduct of bisphenol A represented by the formula (I) as an alcohol component, or Succinic acid substituted with an alkyl group or an alkenyl group as a carboxylic acid component is contained in an alcohol component or a carboxylic acid component, preferably in each of both components. There are 30 to 100 mol%, preferably 50 to 100 mol%, particularly preferably is resin contained 100 mol%. In particular, the resin (2) is preferable because the content of the water-soluble component can be easily reduced by using an alkylene oxide adduct of bisphenol A in the production thereof.
[0017]
In the present invention, the softening point of the amorphous polyester is preferably from 70 to 160 ° C, more preferably from 90 to 150 ° C, from the viewpoint of fixability and storage stability.
[0018]
The glass transition point of the amorphous polyester is preferably from 50 to 80 ° C, more preferably from 55 to 75 ° C, from the viewpoint of fixability and storage stability. The glass transition point is a property unique to an amorphous resin and is distinguished from the maximum peak temperature of heat of fusion.
[0019]
When the amorphous polyester is composed of two or more polyesters, it is desirable that at least one of them, preferably all of them, is an amorphous polyester having the physical properties described above. In particular, from the viewpoint of the fixability and the dispersibility of the colorant and the release agent, the softening point is 70 ° C or higher, a low softening point polyester having a softening point of 120 ° C or more and less than 120 ° C, and a high softening point polyester having a softening point of 160 ° C or less. However, it is preferable to use them together in a weight ratio of 20/80 to 80/20 (low softening point polyester / high softening point polyester).
[0020]
The content of the water-soluble component in the amorphous polyester is 3 mg / g or less, preferably 1 mg / g in terms of carbon in order to prevent hygroscopicity and the generation of voids due to water and the water-soluble component itself. Or less, more preferably 0.1 mg / g or less.
The content of the water-soluble component can be adjusted by a method such as the content of the water-soluble compound in the raw material monomer, particularly the content of the low-molecular weight compound, the reaction rate, the reaction procedure, and the reduced pressure topping after the completion of the reaction.
[0021]
On the other hand, the crystalline polyester is obtained by condensation polymerization of a carboxylic acid component containing 60 mol% or more of an alcohol component and an aliphatic dicarboxylic acid compound having 2 to 8, preferably 4 to 6, and more preferably 4 carbon atoms. Resins are preferred.
[0022]
It is desirable that the aliphatic dicarboxylic acid compound having 2 to 8 carbon atoms is contained in the carboxylic acid component in an amount of 60 mol% or more, preferably 80 to 100 mol%, more preferably 90 to 100 mol%. In particular, it is desirable that one kind of the aliphatic dicarboxylic acid compound occupies 60 mol% or more, preferably 70 to 100 mol%, more preferably 80 to 100 mol% of the carboxylic acid component. Of these, fumaric acid is preferably contained in the carboxylic acid component in an amount of preferably 60 mol% or more, more preferably 70 to 100 mol%, and particularly preferably 80 to 100 mol%.
[0023]
Further, the alcohol component preferably contains an aliphatic diol having 2 to 6, preferably 4 to 6 carbon atoms. The aliphatic diol having 2 to 6 carbon atoms is desirably contained in the alcohol component at 60 mol% or more, preferably 80 to 100 mol%, more preferably 90 to 100 mol%. In particular, it is desirable that one of the aliphatic diols accounts for 70 mol% or more, preferably 80 to 95 mol% of the alcohol component. In particular, it is desirable that 1,4-butanediol is contained in the alcohol component in an amount of preferably 60 mol% or more, more preferably 70 to 100 mol%, and particularly preferably 80 to 100 mol%.
[0024]
In the present invention, the softening point of the crystalline polyester is from 60 to 150 ° C, preferably from 70 to 140 ° C, and more preferably from 80 to 130 ° C, from the viewpoint of fixability.
[0025]
The content of the water-soluble component of the crystalline polyester is 3 mg / g or less, preferably 0.5 to 3 mg / g, in terms of carbon amount, in order to prevent the occurrence of voids while maintaining the fixing property. Preferably it is 1-2 mg / g. The content of the water-soluble component can be adjusted in the same manner as in the case of the amorphous polyester. In the case of the crystalline polyester, for example, an aliphatic diol having 2 to 6 carbon atoms, preferably 2 to 4 carbon atoms It is effective to adjust the content, the reaction rate, and the molar ratio to the carboxylic acid component.
[0026]
Both the amorphous polyester and the crystalline polyester have an alcohol component and a carboxylic acid component, for example, in an inert gas atmosphere, if necessary, using an esterification catalyst, a polymerization inhibitor, etc. It is obtained by condensation polymerization by reacting at a temperature of ° C. Specifically, the reaction is promoted by reducing the pressure of the reaction system in the latter half of the polymerization, for example, to 10 kPa or less, as a means of charging all the monomers at once to increase the strength of the resin or increasing the molecular weight of the polyester. The method of making it effective is also effective.
[0027]
In the present invention, the amorphous polyester is preferably contained as a main component of the binder resin in order to enhance the dispersibility of the crystalline polyester. The content of the amorphous polyester in the binder resin is preferably 50 to 99% by weight, more preferably 50 to 95% by weight, and particularly preferably 70 to 90% by weight.
[0028]
The weight ratio of the amorphous polyester to the crystalline polyester (amorphous polyester / crystalline polyester) is preferably 50/50 to 99/1, more preferably 50/50 to 95/5, and 70/30 to 90 /. 10 is particularly preferred.
[0029]
As the binder resin, as long as the effects of the present invention are not impaired, amorphous polyester polyamides, vinyl resins such as styrene-acrylic resins, and hybrid resins in which two or more resin components are partially chemically bonded are appropriately used. It may be blended.
[0030]
The toner of the present invention further includes a coloring agent, a charge control agent, a release agent, a conductivity adjusting agent, an extender, a reinforcing filler such as a fibrous component, an antioxidant, an antioxidant, a fluidity improver, An additive such as a cleaning improver may be appropriately contained.
[0031]
As the colorant, any of dyes and pigments used as toner colorants can be used, and carbon black, phthalocyanine blue, permanent brown FG, brilliant first scarlet, Pigment Green B, Rhodamine-B base, Solvent Red 49, Solvent Red 146, Solvent Blue 35, Quinacridone, Carmine 6B, Disazo Yellow, and the like. These can be used alone or as a mixture of two or more kinds. It can be used for both toner and full-color toner. The content of the colorant is preferably 1 to 40 parts by weight, more preferably 3 to 10 parts by weight, based on 100 parts by weight of the binder resin.
[0032]
Examples of the charge control agent include a nigrosine dye, a triphenylmethane-based dye containing a tertiary amine as a side chain, a quaternary ammonium salt compound, a polyamine resin, a positive charge control agent such as an imidazole derivative, and a metal-containing azo dye; Negatively chargeable charge control agents such as phthalocyanine dyes, metal complexes of alkyl derivatives of salicylic acid, and boron complexes of benzylic acid.
[0033]
Examples of the release agent include natural ester waxes such as carnauba wax and rice wax, synthetic waxes such as polypropylene wax, polyethylene wax and Fischer-Tropsch, coal waxes such as montan wax, and waxes such as alcohol waxes. These may be contained alone or as a mixture of two or more. Generally, it is preferable to use a wax having a relatively low melting point, such as carnauba wax, in order to obtain excellent low-temperature fixability.
[0034]
The toner of the present invention may be obtained by any conventionally known method such as a kneading and pulverizing method, an emulsification phase inversion method, a polymerization method, etc., but the production is easy and the effects of the present invention are remarkable. Thus, a pulverized toner obtained by a kneading pulverization method is preferable. When a toner is obtained by a kneading and pulverizing method, a binder resin, a colorant, and the like are uniformly mixed with a mixer such as a Henschel mixer, and then melt-kneaded with a closed kneader or a single- or twin-screw extruder, and the like. It can be manufactured by cooling, pulverizing, and classifying.In the emulsification phase inversion method, after dissolving or dispersing a binder resin, a colorant, and the like in an organic solvent, emulsifying by adding water, and then separating and classifying. Can be manufactured. Further, a fluidity improver such as hydrophobic silica may be externally added to the surface of the toner as needed. The volume average particle diameter of the toner is preferably 3 to 15 μm.
[0035]
The toner of the present invention is used alone as a developer when it contains a magnetic fine powder, as a non-magnetic one-component developer when it does not contain a magnetic fine powder, or as a two-component developer when mixed with a carrier. It can be used as an agent.
[0036]
The toner of the present invention is extremely excellent in fixability in non-contact fixing, and can prevent generation of voids, which is a problem specific to non-contact fixing. In particular, it can be suitably used as a flash fixing toner that performs radiant heating in a flash manner.
In flash fixing, the toner image is irradiated with light having a high luminous intensity such as xenon, neon, argon, and krypton lamps for 0.1 to 3 milliseconds to give a heat amount of about 0.5 to 5 joules / cm ² , It is preferable that the toner image is fused and fixed.
[0037]
【Example】
(Softening point)
Using a Koka type flow tester (CFT-500D, manufactured by Shimadzu Corporation), a load of 1.96 MPa was applied by a plunger while heating 1 g of the sample at a heating rate of 6 ° C./min. A 1 mm long nozzle is extruded to draw a plunger descent amount (flow value) -temperature curve of the flow tester. When the height of the S-shaped curve is h, the temperature corresponding to h / 2 (resin) Is the softening point).
[0038]
(Maximum heat of fusion peak temperature and glass transition point)
The temperature was raised to 200 ° C. using a differential scanning calorimeter (DSC210, manufactured by Seiko Instruments Inc.), and the sample cooled from that temperature to 0 ° C. at a rate of 10 ° C./min was measured at a rate of 10 ° C./min. The maximum peak temperature of heat of fusion is determined. Further, the glass transition point is the temperature at the intersection of the tangent line showing the maximum slope from the extension of the baseline below the maximum peak temperature and the rising portion of the peak to the peak of the peak in the measurement, and the It is a unique physical property.
[0039]
(Content of water-soluble component)
2.5 g of a sample that passes through a sieve having an opening of 1 mm but does not pass through a sieve having an opening of 750 μm is mixed with 250 ml of pure water, and shaken at 20 ° C. for 24 hours. After the mixture of the sample and water was filtered through a membrane filter having a pore size of 0.2 μm, the carbon concentration (ppm) in the filtrate was measured by a carbon content measuring device “EMIA-110” (manufactured by HORIBA). :
[0040]
(Equation 1)

[0041]
To calculate the content of the water-soluble component.
[0042]
Production Example of Crystalline Polyester The starting monomers shown in Table 1, 2 g of hydroquinone and 4 g of dibutyltin oxide were reacted in a nitrogen atmosphere at 160 ° C. for 5 hours, and then heated to 200 ° C. for 1 hour. Further, the reaction was carried out at 8.3 kPa until a desired softening point was obtained, thereby obtaining resins a to e.
[0043]
[Table 1]

[0044]
Production Example of Amorphous Polyester A raw material monomer other than trimellitic anhydride shown in Table 2 and 4 g of dibutyltin oxide were reacted under a nitrogen atmosphere at 220 ° C. for 8 hours, and further reacted at 8.3 kPa for 1 hour. I let it. Further, trimellitic anhydride was added to the reaction system at 210 ° C., and reacted until a desired softening point was reached, to obtain resins A and B.
[0045]
[Table 2]

[0046]
Examples 1, 3 to 5, Comparative Examples 1 and 2
100 parts by weight of the binder resin shown in Table 3, 4 parts by weight of carbon black “MOGUL L” (manufactured by Cabot), 1 part by weight of charge control agent “T-77” (manufactured by Hodogaya Chemical Industry Co., Ltd.), and carnauba wax After thoroughly mixing 1 part by weight of "Carnauba wax C1" (manufactured by Kato Yoko Co., Ltd.) with a Henschel mixer, a co-rotating twin-screw extruder (total length of kneading part: 1560 mm, screw diameter: 42 mm, barrel inner diameter: 43 mm) is used. The melt kneading was performed by adjusting the roll rotation speed to 200 rotations / minute, the heating temperature in the roll to 100 ° C., and the mixture supply speed to 10 kg / hour. The average residence time of the mixture was about 18 seconds. After cooling and coarsely pulverizing the obtained melt-kneaded material, it was pulverized and classified by a jet mill to obtain a powder having a volume average particle diameter of 8.0 μm. To 100 parts by weight of the obtained powder, 1.0 part by weight of "Aerosil R-972" (manufactured by Nippon Aerosil Co., Ltd.) as an external additive was added and mixed with a Henschel mixer to obtain a toner.
[0047]
Example 2
1 part by weight of "LR-147" (manufactured by Nippon Carlit) instead of "T-77" as a charge control agent, and 4 parts by weight of cyan pigment "ECB-301" (manufactured by Dainichi Seika) instead of carbon black The toner was obtained in the same manner as in Example 1 except that the respective parts were used.
[0048]
Test Example 1 [Evaluation of fixability]
A developer was obtained by mixing 4 parts by weight of the toner and 96 parts by weight of a silicon-coated ferrite carrier (manufactured by Kanto Denka Kogyo KK, average particle size: 90 μm) with a turbuler mixer for 10 minutes. Next, the developer is mounted on a copier “AR-505” (manufactured by Sharp Corporation), the toner adhesion amount is adjusted to 0.6 mg / cm ^2, and “Copy Bond SF-70NA” (manufactured by Sharp Corporation) is used as fixing paper. , 75 g / m ² ) to obtain an unfixed image of 2 cm × 12 cm.
[0049]
The unfixed image was flash-fixed using a xenon lamp as a flash lamp under the conditions that the pulse duration was 1 millisecond and the energy of the flash lamp was 3.0 joules / cm ^{2 on} the surface of the image bearing sheet.
[0050]
The obtained fixed image was rubbed five times with a sand eraser of 15 mm × 7.5 mm under a load of 500 g under a load of 500 g, and the optical reflection density before and after rubbing was measured using a reflection densitometer “RD-915” (manufactured by Macbeth). The ratio of the two (after rubbing / before rubbing) was determined as the fixing rate, and the fixing property was evaluated according to the following evaluation criteria. Table 3 shows the results.
[0051]
〔Evaluation criteria〕
Fixing ratio: ：: 90% or more ：: 70% or more and less than 90% X: less than 70%
Test Example 2 [Evaluation of image quality]
A 2 cm × 12 cm unfixed image obtained in the same manner as in Test Example 1 was flashed in the same manner as in Test Example 1 except that the energy of the flash lamp was changed to 4.0 Joules / cm ² on the surface of the image bearing sheet. Established. The presence or absence of voids due to generation of voids in the obtained fixed image was visually observed, and the image quality was evaluated based on the following evaluation criteria. Table 3 shows the results.
[0053]
〔Evaluation criteria〕
：: Almost no white spots.
Δ: White spots are slightly observed.
×: Many white spots.
[0054]
[Table 3]

[0055]
From the above results, the toner of Example has good fixability, and a high-quality image with few voids due to voids is obtained, whereas the toner of Comparative Example 1 having high water solubility has a problem in fixability. Although no toner was present, voids were generated, and it can be seen that the toner of Comparative Example 2 using no crystalline polyester lacks fixability.
[0056]
【The invention's effect】
According to the present invention, it is possible to provide a non-contact fixing toner which is excellent in fixing property and in which a high quality image can be obtained without generating voids.

Claims (5)

Amorphous polyester having a ratio of softening point and maximum peak temperature of heat of fusion (softening point / peak temperature) of more than 1.3 and 4.0 or less, and a ratio of softening point and maximum peak temperature of heat of fusion (softening point / peak temperature) A non-contact fixing toner containing a crystalline polyester having a peak temperature of 0.6 to 1.3 as a binder resin, wherein the crystalline polyester has a softening point of 60 to 150 ° C., A non-contact fixing toner in which the content of a water-soluble component in each of the crystalline polyester and the amorphous polyester is 3 mg / g or less in terms of carbon. 2. The non-contact fixing toner according to claim 1, wherein the weight ratio of the amorphous polyester to the crystalline polyester is 50/50 to 95/5. The amorphous polyester has the formula (I):

(Wherein, R is an alkylene group having 2 or 3 carbon atoms, x and y are positive numbers, and the sum of x and y is 1 to 16)
The non-contact fixing toner according to claim 1, which is a resin obtained by polycondensing an alcohol component containing a bisphenol A alkylene oxide adduct represented by formula (1) and a carboxylic acid component. The crystalline polyester is a resin obtained by condensation-polymerizing a carboxylic acid component containing an alcohol component and an aliphatic dicarboxylic acid compound having 2 to 8 carbon atoms in an amount of 60 mol% or more. Non-contact fixing toner. The non-contact fixing toner according to claim 1, which is used for flash fixing.