JP4181700B2 - Frictional charging member and developing device using the same - Google Patents

Description

（式中のＲ₁，Ｒ₂，Ｒ₃及びＲ₄は、各々、置換基を有しても良いアルキル基、置換基を有しても良いアリール基、アルアルキル基を表し、各々同一でもあるいは異なっていてもよい。Ｘ^-は酸の陰イオンを表す。）
【００３８】
これに対し、例えば下記式（ＩＩ）で表されるような、それ自身が鉄粉に対して負帯電性を有する含フッ素４級アンモニム塩化合物についても検討を行ったが、該化合物の添加によっては本発明の所期の目的が達成されないことがわかった。即ち、下記式（ＩＩ）で表される化合物は、電子吸引性の強いフッ素樹脂原子が構造中にあるので、それ自身が鉄粉に対して負帯電性を有するが、本発明の場合と同様に、該化合物を樹脂中に分散させた樹脂組成物を被覆樹脂とし、これを加熱乾燥させてキャリア芯材に被覆層を形成しても、それ自身が鉄粉に対して正帯電性である第４級アンモニウム塩化合物を含有させた樹脂を被覆樹脂に用いる本発明の場合ほどには、正帯電性の現像剤に対する高い摩擦帯電付与性は得られなかった。
【００３９】
【化６】

【００４０】
本発明に好適に用いられる、それ自身が鉄粉に対して正帯電性である第４級アンモニウム塩化合物としては、具体的には、以下のようなものが挙げられるが、勿論、本発明は、これらに限定されるものではない。
【００４１】
【化７】

【００４２】
上記に示したような本発明で使用する第４級アンモニウム塩化合物の添加量は、被覆樹脂１００重量部に対して１〜１００重量部とすることが好ましい。１重量部未満では添加による帯電付与性の向上が見られず、１００重量部を超えると樹脂中への分散不良となり被膜強度の低下を招きやすい。
【００４３】
本発明の被覆層に用いられる樹脂として特に限定はされないが、樹脂の一部又は全部がその分子構造中に少なくとも−ＮＨ₂基、＝ＮＨ基、もしくは−ＮＨ−結合のいずれかの構造を有していることが好ましい。このような樹脂を用いて被覆層を形成することで、本発明の効果が容易に発揮可能である。本発明において、摩擦帯電付与部材の樹脂層として上記のような構造のものを用いると、自身が負帯電付与性へと変化することについての明確な理由は定かではないが、本発明で用いる、それ自身が鉄粉に対して正帯電性である第４級アンモニウム塩化合物及び、−ＮＨ₂基、＝ＮＨ基、もしくは−ＮＨ−結合の少なくとも一つの構造を有している樹脂を用いて樹脂被覆層を形成することにより樹脂の構造中に第４級アンモニウム塩が取り込まれる。その際、正極性を有する第４級アルコール塩の元の構造が失われ、これらを取り込んだ樹脂の帯電性が均一且つ十分な負帯電性を有するようになるためではないかと考えられる。
【００４４】
▲１▼−ＮＨ₂基を有する物質としては、Ｒ−ＮＨ₂で表される第１アミンもしくはそれらを有するポリアミン、ＲＣＯ−ＮＨ₂で表される第１アミドもしくはそれらを有するポリアミド等、▲２▼＝ＮＨ基を有する物質としては、Ｒ＝ＮＨで表される第２アミンもしくはそれらを有するポリアミン、（ＲＣＯ）₂＝ＮＨで表される第２アミドもしくはそれらを有するポリアミド等、▲３▼−ＮＨ−結合を有する物質としては、前述したポリアミン、ポリアミド等の他、−ＮＨＣＯＯ−結合を有するポリウレタン等が挙げられ、以上の物質を１種又は２種以上、あるいは共重合体として含有し、工業的に合成された樹脂が好適に用いられる。それらのうち汎用性等の面から、アンモニアを触媒としたフェノール樹脂、ポリアミド樹脂及びウレタン樹脂等が好ましい。
【００４５】
本発明に使用される含窒素複素環化合物としては、イミダゾール、イミダゾリン、イミダゾロン、ピラゾリン、ピラゾール、ピラゾロン、オキサゾリン、オキサゾール、オキサゾロン、チアゾリン、チアゾール、チアゾロン、セレナゾリン、セレナゾール、セレナゾロン、オキサジアゾール、チアジアゾール、テトラゾール、ベンゾイミダゾール、ベンゾトリアゾール、ベンゾオキサゾール、ベンゾチアゾール、ベンゾセレナゾール、ピラジン、ピリミジン、ピリダジン、トリアジン、オキサジン、チアジン、テトラジン、ポリアザイン、ピリダジン、ピリミジン、ピラジン、インドール、イソインドール、インダゾール、カルバゾール、キノリン、ピリジン、イソキノリン、シンノリン、キナゾリン、キナキサリン、フタラジン、プリン、ピロール、トリアゾール、フェナジン等の含窒素複素環基を有する化合物が挙げられる。本発明においては、特にイミダゾール化合物が、本発明に用いられる現像剤担持体とトナーとの相互作用による効果を促進するため、好ましい。
【００４６】
特に、イミダゾール化合物の中でも、下記一般式（１）または（２）
【００４７】
【化８】

〔式中、Ｒ₁及びＲ₂は、水素原子、アルキル基、アラルキル基またはアリール基を表し、Ｒ₁及びＲ₂は同一であっても異なっていても良い。Ｒ₃及びＲ₄は炭素数が３〜３０の直鎖状のアルキル基を表し、Ｒ₃及びＲ₄は同一であっても良い。〕
【００４８】
【化９】

〔式中、Ｒ₅及びＲ₆は、水素原子、アルキル基、アラルキル基またはアリール基を表し、Ｒ₅及びＲ₆は同一であっても良い。Ｒ₇は、炭素数が３〜３０の直鎖状のアルキル基を表す。〕
で示されるイミダゾール化合物が該トナーの迅速且つ均一な帯電性及び被覆層の強度の点でより好ましい。
【００４９】
その理由は、前記の一般式（１）又は（２）で示す構造のイミダゾール化合物は、置換基として炭素数３〜３０の直鎖状アルキル基を有することで、被覆層の樹脂に対する分散性が良好であり、且つ、本発明に使用する特別な表面での分散状態からなるトナーとの摩擦帯電特性が良好であるためと考えられる。
【００５０】
また、前記の含窒素複素環化合物を構成する含窒素複素環基は、単環であっても他の基と縮環していても良く、また置換されていても良い。
【００５１】
この含窒素複素環基が置換されている場合に、置換基としては、例えばアルキル基、アラルキル基、アルケニル基、アルキニル基、アルコキシ基、アリール基、置換アミノ基、ウレイド基、ウレタン基、アリールオキシ基、スルファモイル基、カルバモイル基、アルキルまたはアリールチオ基、アルキルまたはアリールスルホニル基、アルキルまたはアリールスルフィニル基、ヒドロキシ基、ハロゲン原子、シアノ基、スルホ基、アリールオキシカルボニル基、アシル基、アルコキシカルボニル基、アシルオキシ基、カルボンアミド基、スルホンアミド基、カルボキシル基、リン酸アミド基、ジアシルアミノ基、イミド基等を用いることができる。上記の置換基は更に置換基を有していても良い。その置換基の例としては、含窒素複素環の置換基で挙げた置換基を用いることができる。
【００５２】
上記の含窒素複素環化合物は、個数平均粒径が好ましくは２０μｍ以下、より好ましくは０．１〜１５μｍのものを使用するのが良い。含窒素複素環化合物の個数平均粒径が２０μｍを超える場合には、該樹脂被覆層中への含窒素複素環化合物の分散性不良により帯電性能の向上効果が充分に得られ難く好ましくない。
【００５３】
被覆層の結着樹脂材料としては、一般に公知の樹脂が使用可能である。例えば、スチレン系樹脂、ビニル系樹脂、ポリエーテルスルホン樹脂、ポリカーボネート樹脂、ポリフェニレンオキサイド樹脂、ポリアミド樹脂、フッ素樹脂、繊維素系樹脂、アクリル系樹脂、エポキシ樹脂、ポリエステル樹脂、アルキッド樹脂、フェノール樹脂、メラミン樹脂、ポリウレタン樹脂、尿素樹脂、シリコーン樹脂及びポリイミド樹脂等の熱可塑性樹脂、または光硬化性樹脂等を使用することができる。中でも、シリコーン樹脂及びフッ素樹脂等の離型性のあるもの、あるいはポリエーテルスルホン、ポリカーボネート、ポリフェニレンオキサイド、ポリアミド、フェノール、ポリエステル、ポリウレタン、スチレン系樹脂及びアクリル樹脂等の機械的に優れたものがより好ましい。
【００５４】
ただし、本発明の目的を容易に達成するためには、前述の如く、−ＮＨ₂基、＝ＮＨ基、もしくは−ＮＨ−結合の少なくとも一つの構造を有している結着樹脂を用いることが好ましい。また、上記一般的な結着樹脂と混合して用いることも可能である。
【００５５】
本発明の摩擦帯電付与材は該被覆層の体積抵抗を調整する為、結着樹脂中に他の導電性微粒子を分散含有させても良い。このような導電性微粒子としては、個数平均粒径が２０μｍ以下が好ましく、１０μｍ以下がより好ましい。樹脂表面に形成される凹凸を避けるためには、１μｍ以下のものを用いる。
【００５６】
本発明で使用される導電性微粒子の構成としては、ファーネスブラック、ランプブラック、サーマルブラック、アセチレンブラック、チャンネルブラック等のカーボンブラック；酸化チタン、酸化スズ、酸化亜鉛、酸化モリブデン、チタン酸カリ、酸化アンチモン及び酸化インジウム等の金属酸化物等；アルミニウム、銅、銀、ニッケル等の金属、グラファイト、金属繊維、炭素繊維等の無機系充填剤等が挙げられる。
【００５７】
上述した被覆層中の導電性微粒子の添加量としては、結着樹脂１００重量部に対して１００重量部以下の範囲が好ましい結果を与える。添加量が１００重量部を超えると被膜強度の低下が起こり易く、また多量の非帯電性粒子の添加は、トナーの帯電量の低下が生じうる。
【００５８】
また、本発明の摩擦帯電付与材の樹脂被覆層の構成としては、潤滑性物質を被覆樹脂層中に分散させることで、より本発明の効果が促進されるので好ましい。潤滑性物質としては、例えばグラファイト、二硫化モリブデン、窒化硼素、雲母、フッ化グラファイト、銀−セレン化ニオブ、塩化カルシウム−グラファイト、滑石、ステアリン酸亜鉛等の脂肪酸金属塩等が挙げられ、特にグラファイトが被覆層の導電性を損なわないので好ましく用いられる。これらの潤滑性物質は、個数平均粒径が好ましくは０．２〜２０μｍ程度、より好ましくは０．３〜１５μｍのものを使用するのがよい。
【００５９】
上記潤滑性物質の添加量としては、結着樹脂１００重量部に対して１０〜１２０重量部の範囲で特に好ましい結果を与える。添加量が１２０重量部を超える場合は被膜強度の低下が生じ易く、また非帯電性の添加物を多量に添加することは、トナーの帯電量の低下が発生する。逆に１０重量部未満では摩擦帯電付与部材へのトナー付着防止に対する添加効果を得ることができにくい。
【００６０】
次に本発明に用いられる現像剤担持体の構成について説明を加える。現像剤担持体は基体と、それを取り巻いて被覆する樹脂層とからなる。基体としては、円筒状部材、円柱状部材、ベルト状部材等があるが、ドラムに非接触の現像方法においては金属の円筒管が好ましく用いられる。金属円筒管は主としてステンレススチール、アルミニウムおよびその合金等の非磁性のものが好適に用いられる。また、ドラムに直接接触させる現像方法の場合の基体としては、ウレタン、ＥＰＤＭ、シリコーン等のゴムやエラストマーを含む層構成を有する円筒部材が好ましく用いられる。
【００６１】
また、現像剤担持体の樹脂被覆層の構成として、前述した添加物質に加えて、粒径が０．３〜３０μｍの球状粒子を被覆樹脂層中に分散させることで、表面粗さを安定化させ、現像剤担持体上のトナーコート量を最適化することが可能である。該球状粒子は、現像剤担持体の被覆層表面に均一な表面粗度を保持させると同時に、被覆層表面が摩耗した場合でも被覆層の表面粗度の変化が少なく、且つトナー汚染やトナー融着を発生しにくくする効果がある。
【００６２】
本発明に使用される球状粒子としては、個数平均粒径が好ましくは０．３〜３０μｍ、より好ましくは２〜２０μｍである。球状粒子の個数平均粒径が０．３μｍ未満では表面に均一な粗さを付与する効果と帯電性能を高める効果が少なく、現像剤への迅速且つ均一な帯電が不十分となると共に、被覆層の磨耗によるトナーのチャージアップ、トナー汚染及びトナー融着が発生し、ゴースト抑制の悪化、画像濃度低下を生じやすくなるため好ましくない。個数平均粒径が３０μｍを超える場合には、被覆層表面の粗さが大きくなり過ぎ、トナーの帯電が十分に行なわれにくくなってしまうと共に、被覆層の機械的強度が低下してしまうため好ましくない。
【００６３】
さらに好ましくは、球状粒子の真密度は、３．０ｇ／ｃｍ³以下、好ましくは２．７ｇ／ｃｍ³以下、より好ましくは０．９〜２．３ｇ／ｃｍ³であることが良い。即ち、球状粒子の真密度が３．０ｇ／ｃｍ³を超える場合には、被覆層中での球状粒子の分散性が不十分となる為、被覆層表面に均一な粗さを付与しにくくなる。また、塗料の保存安定性が良くないため、ここでも均一表面凹凸を有する摩擦帯電付与部材表面が得にくくなる。球状粒子の真密度が０．９ｇ／ｃｍ³より小さい場合にも、被覆層中での球状粒子の分散性が不十分となる。
【００６４】
本発明において、球状粒子における球状とは、粒子の長径／短径の比が１．０〜１．５程度のものを意味しており、本発明において好ましくは、長径／短径の比が１．０〜１．２の粒子を使用することが良い。球状粒子の長径／短径の比が１．５を超える場合には、被覆層表面粗さの不均一化が発生し、トナーの迅速且つ均一な帯電化及び導電性被覆層の強度の点で好ましくない。
【００６５】
本発明に用いられる球状粒子は、公知の球状粒子が使用可能である。例えば、球状の樹脂粒子、球状の金属酸化物粒子、球状の炭素化物粒子などがある。
【００６６】
球状の樹脂粒子としては、例えば、懸濁重合、分散重合法等による球状の樹脂粒子などが用いられる。球状の樹脂粒子は、より少ない添加量で好適な表面粗さが得られ、更に均一な表面形状が得られやすい。この様な球状粒子としては、ポリアクリレート、ポリメタクリレート等のアクリル系樹脂粒子、ナイロン等のポリアミド系樹脂粒子、ポリエチレン、ポリプロピレン等のポリオレフィン系樹脂粒子、シリコーン系樹脂粒子、フェノール系樹脂粒子、ポリウレタン系樹脂粒子、スチレン系樹脂粒子、ベンゾグアナミン粒子、等々が挙げられる。粉砕法により得られた樹脂粒子を熱的にあるいは物理的な球形化処理を行ってから用いてもよい。
【００６７】
また、該球状粒子の表面に無機物を付着あるいは固着させて用いてもよい。この様な無機微粉体としては、ＳｉＯ₂，ＳｒＴｉＯ₃，ＣｅＯ₂，ＣｒＯ，Ａｌ₂Ｏ₃，ＺｎＯ，ＭｇＯの如き酸化物、Ｓｉ₃Ｎ₄の如き窒化物、ＳｉＣの如き炭化物、ＣａＳＯ₄，ＢａＳＯ₄，ＣａＣＯ₃の如き硫酸塩・炭酸塩、等々が挙げられる。
【００６８】
このような無機微粉末は、カップリング剤により処理して用いても良い。特に結着樹脂との密着性を向上させる目的、あるいは粒子に疎水性を与える、等々の目的で好ましく用いることが可能である。このようなカップリング剤としては、例えば、シランカップリング剤、チタンカップリング剤、ジルコアルミネートカップリング剤等がある。より具体的には、例えばシランカップリング剤としては、ヘキサメチルジシラザン、トリメチルシラン、トリメチルクロルシラン、トリメチルエトキシシラン、ジメチルジクロルシラン、メチルトリクロルシラン、アリルジメチルクロルシラン、アリルフェニルジクロルシラン、ベンジルジメチルクロルシラン、ブロムメチルジメチルクロルシラン、α−クロルエチルトリクロルシラン、β−クロルエチルトリクロルシラン、クロルメチルジメチルクロルシラン、トリオルガノシリルメルカプタン、トリメチルシリルメルカプタン、トリオルガノシリルアクリレート、ビニルジメチルアセトキシシラン、ジメチルジエトキシシラン、ジメチルジメトキシシラン、ジフェニルジエトキシシラン、ヘキサメチルジシロキサン、１，３−ジビニルテトラメチルジシロキサン、１，３−ジフェニルテトラメチルジシロキサン及び１分子当たり２から１２個のシロキサン単位を有し末端に位置する単位にそれぞれ１個宛の硅素原子に結合した水酸基を含有したジメチルポリシロキサン等が挙げられる。このように球状樹脂粒子表面に対して無機微粉末で処理することにより、被覆層中への分散性、被覆層表面の均一性、被覆層の耐汚染性、トナーヘの帯電付与性、被覆層の耐磨耗性等を向上させることができる。
【００６９】
また、本発明に使用する球状粒子は、導電性であることが好ましい。即ち、球状粒子に導電性を持たせることによって、その導電性のゆえに粒子表面にチャージが蓄積しにくく、トナー付着の軽減やトナーの帯電付与性を向上させることができるからである。本発明において、球状粒子の導電性としては、体積抵抗値が１０⁶Ω・ｃｍ以下、より好ましくは１０^-3〜１０⁶Ω・ｃｍの粒子であることが好ましい。
【００７０】
本発明において、球状粒子の体積抵抗が１０⁶Ω・ｃｍを超えると、摩耗によって被覆層表面に露出した球状粒子を核としてトナーの汚染や融着を発生しやすくなるとともに、迅速且つ均一な帯電が行われにくくなるため、好ましくない。
【００７１】
このような導電性球状粒子を得る方法としては、以下に示す様な方法が好ましいが、必ずしもこれらの方法に限定されるものではない。
【００７２】
本発明に使用される特に好ましい導電性球状粒子を得る方法としては、例えば、樹脂系球状粒子やメソカーボンマイクロビーズを焼成して炭素化及び／又は黒鉛化して得た低密度且つ良導電性の球状炭素粒子を得る方法が挙げられる。そして、樹脂系球状粒子に用いられる樹脂としては、例えば、フェノール樹脂、ナフタレン樹脂、フラン樹脂、キシレン樹脂、ジビニルベンゼン重合体、スチレン−ジビニルベンゼン共重合体、ポリアクリロニトリルが挙げられる。
【００７３】
また、メソカーボンマイクロビーズは、通常、中ピッチを加熱焼成していく過程で生成する球状結晶を多量のタール、中油、キノリンの如き溶剤で洗浄することによって製造することができる。
【００７４】
より好ましい導電性球状粒子を得る方法としては、フェノール樹脂、ナフタレン樹脂、フラン樹脂、キシレン樹脂、ジビニルベンゼン重合体、スチレン−ジビニルベンゼン共重合体、ポリアクリロニトリルの如き球状樹脂粒子表面に、メカノケミカル法によってバルクメソフェーズピッチを被覆し、被覆された粒子を酸化性雰囲気下で熱処理した後に不活性雰囲気下又は真空下で焼成して炭素化及び／又は黒鉛化し、導電性球状炭素粒子を得る方法が挙げられる。この方法で得る球状炭素粒子は、黒鉛化すると得られる球状炭素粒子の被覆部の結晶化が進んだものとなるので導電性が向上し、より好ましい。
【００７５】
上記した方法で得られる導電性の球状炭素粒子は、いずれの方法でも、焼成条件を変化させることによって得られる球状炭素粒子の導電性を制御することが可能であり、本発明において好ましく使用される。また、上記の方法で得られる球状炭素粒子は、場合によっては、更に導電性を高めるために導電性球状粒子の真密度が３ｇ／ｃｍ³を超えない範囲で、導電性の金属及び／または金属酸化物のメッキを施していても良い。
【００７６】
本発明で使用される導電性球状粒子を得る他の方法としては、球状樹脂粒子からなる芯粒子に対して、芯粒子の粒径より小さい粒径の導電性微粒子を適当な配合比で機械的に混合することによって、ファンデルワールス力及び静電気力の作用により、芯粒子の周囲に均一に導電性微粒子を付着した後、例えば機械的衝撃力を付与することによって生ずる局部的温度上昇により芯粒子表面を軟化させ、芯粒子表面に導電性微粒子を成膜して導電化処理した球状樹脂粒子を得る方法が挙げられる。
【００７７】
本発明に使用される導電性球状粒子を得る更に他の方法としては、球状樹脂粒子中に導電性微粒子を均一に分散させることにより、導電性微粒子が分散された導電性球状粒子を得る方法が挙げられる。球状樹脂粒子中に導電性微粒子を均一に分散させる方法としては、例えば、結着樹脂と導電性微粒子とを混練して導電性微粒子を分散させた後、冷却固化し、所定の粒径に粉砕し、機械的処理及び熱的処理により球形化して導電性球状粒子を得る方法；又は、重合性単量体中に重合開始剤、導電性微粒子及びその他の添加剤を加え、分散機によって均一に分散せしめた単量体組成物を、分散安定剤を含有する水相中に撹拌機等によって所定の粒子径になるように懸濁させて重合を行ない、導電性微粒子が分散された球状粒子を得る方法；が挙げられる。
【００７８】
本発明に適用できるキャリア用の芯材は、特別限定されるものではなく、従来公知のすべてのものが、使用可能である。例えば、鉄、ニッケル、コバルトといった磁性体金属、及びそれらの合金、或いは希土類を含有する合金類、ヘマタイト、マグネタイト、マンガン−亜鉛系フェライト、ニッケル−亜鉛系フェライト、マンガン−マグネシウム系フェライト及びリチウム系フェライト等のソフトフェライト、銅−亜鉛系フェライトといった鉄系酸化物、およびそれらの混合物が挙げられる。さらには、ガラス、炭化ケイ素などのセラミックス粒子、樹脂粉体、磁性体を含有する樹脂粉体などをあげることができる。
【００７９】
本発明に適用できる現像剤層厚規制部材の基材は、特別限定されるものではなく、従来公知のすベてのものが、使用可能である。例えば、鉄、ステンレス、ニッケル、アルミニウムなどの金属あるいは合金、および、セラミックス、プラスチックス、ゴムなどの非金属材料などを用い、これらの材料を板状に加工して用いる場合が多いが、ロール形状としても良い。また、金属の基材にゴム板を貼り付けて用いたり、金属の弾性板にスリーブと接触する部分にエラストマー材を貼り付けて用いたりもする。
【００８０】
本発明の樹脂被覆層を形成する方法については、特に限定されない、例えば、摩擦帯電付与部材の基材に、本発明の組成物を含有する塗布液をディッピング法、スプレー法、はけ塗り法などの方法で塗布し乾燥させれば、本発明の摩擦帯電付与部材が得られる。さらに、成形可能な樹脂中に、本発明の化合物を公知の方法で分散含有させた後、スリーブ、ドクターブレード等に成形することにより製造することもできる。
【００８１】
次に、本発明の現像装置で用いられるトナーについて説明する。
【００８２】
トナーは主として樹脂，離型剤，荷電制御剤，着色剤等を溶融混練し、固化した後粉砕し、しかる後分級などをして粒度分布をそろえた微粉体である。
【００８３】
トナーに用いられる結着樹脂としては、一般に公知の樹脂が使用可能である。例えば、スチレン，α−メチルスチレン，ｐ−クロルスチレンなどのスチレン及びその置換体の単重合体；スチレン−プロピレン共重合体，スチレン−ビニルトルエン共重合体，スチレン−アクリル酸エチル共重合体，スチレン−アクリル酸ブチル共重合体，スチレン−アクリル酸オクチル共重合体，スチレン−ジメチルアミノエチル共重合体，スチレン−メタクリル酸メチル共重合体，スチレン−メタクリル酸エチル共重合体，スチレン−メタクリル酸ブチル共重合体，スチレン−メタクリル酸ジメチルアミノエチル共重合体，スチレン−ビニルメチルエーテル共重合体，スチレン−ビニルメチルケトン共重合体，スチレン−ブタジエン共重合体，スチレン−イソプレン共重合体，スチレン−マレイン酸共重合体，スチレン−マレイン酸エステル共重合体などのスチレン系共重合体；ポリメチルメタクリレート，ポリブチルメタクリレート，ポリ酢酸ビニル，ポリエチレン，ポリプロピレン，ポリビニルブチラール，ポリアクリル酸樹脂，ロジン，変性ロジン，テンペル樹脂，フェノール樹脂，脂肪族又は脂環族炭化水素樹脂，芳香族系石油樹脂，パラフィンワックス，カルナバワックスなどが、単独或は混合して使用できる。
【００８４】
また、トナー中には顔料を含有することができる。例えば、カーボンブラック，ニグロシン染料，ランプ黒，スーダンブラックＳＭ，ファースト・イエローＧ，ベンジジン・イエロー，ピグメント・イエロー，インドファースト・オレンジ，イルガジン・レッド，パラニトロアニリン・レッド，トルイジン・レッド，カーミンＦＢ，パーマネント・ボルドーＦＲＲ，ピグメント・オレンジＲ，リソール・レッド２Ｇ，レーキ・レッドＣ，ローダミンＦＢ，ローダミンＢレーキ，メチル・バイオレッドＢレーキ，フタロシアニン・ブルー，ピグメント・ブルー，ブリリアント・グリーンＢ，フタロシアニングリーン，オイルイエローＣＧ，ザボン・ファーストイエローＣＧＧ，カヤセットＹ９６３，カヤセットＹＧ，ザボン・ファーストオレンジＲＲ，オイル・スカーレット，オラゾール・ブラウンＢ，ザボン・ファーストスカーレットＣＧ，オイルピンクＯＰ等が適用できる。
【００８５】
トナーを磁性トナーとして用いるために、トナーの中に磁性粉を含有せしめてもよい。このような磁性粉としては、磁場の中におかれて磁化される物質が用いられ、鉄，コバルト，ニッケル等の強磁性金属の粉末、又はマグネタイト，ヘマタイト，フェライト等の合金や化合物がある。この磁性粉の含有量はトナー重量に対して１５〜７０重量％が良い。
【００８６】
トナーに、定着時の離型性向上、定着性向上の目的で、ワックス類を含有させることができる。そのようなワックス類としては、パラフィンワックス及びその誘導体、マイクロクリスタリンワックス及びその誘導体、フィッシャートロプッシュワックス及びその誘導体、ポリオレフィンワックス及びその誘導体、カルナバワックス及びその誘導体などで、誘導体には酸化物や、ビニル系モノマーとのブロック共重合物、グラフト変性物を含む。その他、アルコール、脂肪酸、酸アミド、エステル、ケトン、硬化ヒマシ油及びその誘導体、植物系ワックス、動物系ワックス、鉱物系ワックス、ペトロラクタム等も利用できる。
【００８７】
必要に応じて、トナーに荷電制御剤を含有させてもよい。荷電制御剤には、負荷電制御剤、正荷電制御剤がある。例えばトナーを負荷電性に制御するものとして下記物質がある。例えば有機金属錯体、キレート化合物が有効であり、モノアゾ金属錯体、アセチルアセトン金属錯体、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錯体がある。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。また、トナーを正帯電させるための物質としては下記のようなものがある。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等の四級アンモニウム塩、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（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等のジ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等のジオルガノスズボレート類；グアニジン化合物、イミダゾール化合物などである。
【００８８】
トナーは必要に応じて、流動性改善等の目的で無機微粉末の如き粉末を外添して用いられる。このような微粉末としては、シリカ微粉末、アルミナ、チタニア、酸化ゲルマニウム、酸化ジルコニウム等の金属酸化物；炭化ケイ素、炭化チタン等の炭化物；及び窒化ケイ素、窒化ゲルマニウム等の窒化物等の無機微粉体が用いられる。これらの微粉体は、有機ケイ素化合物、チタンカップリング剤等で有機処理して用いることが可能である。例えば有機ケイ素化合物としては、ヘキサメチルジシラザン、トリメチルシラン、トリメチルクロルシラン、トリメチルエトキシシラン、ジメチルジクロルシラン、メチルトリクロルシラン、アリルジメチルクロルシラン、アリルフェニルジクロルシラン、ベンジルジメチルクロルシラン、ブロムメチルジメチルクロルシラン、α−クロルエチルトリクロルシラン、β−クロルエチルトリクロルシラン、クロルメチルジメチルクロルシラン、トリオルガノシリルメルカプタン、トリメチルシリルメルカプタン、トリオルガノシリルアクリレート、ビニルジメチルアセトキシシラン、ジメチルエトキシシラン、ジメチルジメトキシシラン、ジフェニルジエトキシシラン、ヘキサメチルジシロキサン、１，３−ジビニルテトラメチルジシロキサン、１，３−ジフェニルテトラメチルジシロキサン、および１分子当り２から１２個のシロキサン単位を有し末端に位置する単位にそれぞれ１個宛のＳｉに結合した水酸基を含有するジメチルポリシロキサン等がある。また、未処理の微粉体を窒素含有のシランカップリング剤で処理したものを用いてもよい。特に正帯電性トナーの場合好ましい。そのような処理剤の例としては、アミノプロピルトリメトキシシラン、アミノプロピルトリエトキシシラン、ジメチルアミノプロピルトリメトキシシラン、ジエチルアミノプロピルトリメトキシシラン、ジプロピルアミノプロピルトリメトキシシラン、ジブチルアミノプロピルトリメトキシシラン、モノブチルアミノプロピルトリメトキシシラン、ジオクチルアミノプロピルトリメトキシシラン、ジブチルアミノプロピルジメトキシシラン、ジブチルアミノプロピルモノメトキシシラン、ジメチルアミノフェニルトリメトキシシラン、トリメトキシシリル−γ−プロピルフェニルアミン、トリメトキシシリル−γ−プロピルベンジルアミン、トリメトキシシリル−γ−プロピルピペリジン、トリメトキシシリル−γ−プロピルモルホリン、トリメトキシシリル−γ−プロピルイミダゾール等がある。
【００８９】
上記シランカップリング剤により無機微粉体を処理する方法としては、例えば、１）スプレー法，２）有機溶媒法，３）水溶液法などがある。一般に、スプレー法による処理とは、ピグメントを撹拌しここにカップリング剤の水溶液あるいは溶媒液をスプレーし、この後水あるいは溶媒を１２０〜１３０℃程度で除去乾燥する方法である。また、有機溶媒法による処理とは、少量の水とともに加水分解用触媒を含む有機溶媒（アルコール，ベンゼン，ハロゲン化炭化水素等）にカップリング剤を溶解し、これにピグメントを浸積した後、濾過或は圧搾により固液分離を行い１２０〜１３０℃程度で乾燥させるものである。水溶液法とは、０．５％程度のカップリング剤を、一定ｐＨの水あるいは水−溶媒中で加水分解させ、ここにピグメントを浸積し後、同様に固液分離を行い乾燥するものである。
【００９０】
他の有機処理としてシリコーンオイルで処理された微粉体を用いることも可能である。好ましいシリコーンオイルとしては、２５℃における粘度がおよそ０．５〜１００００ｍｍ²／ｓ、好ましくは１〜１０００ｍｍ²／ｓのものが用いられ、例えばメチルハイドロジェンシリコーンオイル、ジメチルシリコーンオイル、フェニルメチルシリコーンオイル、クロルフェニルメチルシリコーンオイル、アルキル変性シリコーンオイル、脂肪酸変性シリコーンオイル、ポリオキシアルキレン変性シリコーンオイル、フッ素変性シリコーンオイルなどが挙げられる。また、側鎖に窒素原子を有するシリコーンオイルを用いても良い。特に正帯電性トナーの場合は好ましい。シリコーンオイルによる処理は、例えば次のようにして行ない得る。必要に応じて加熱しながら顔料を激しく撹乱しており、これに上記シリコーンオイル或いはその溶液をスプレーもしくは気化して吹き付けるか、または顔料をスラリー状にしておき、これを撹拌しつつシリコーンオイル或いはその溶液を滴下することによって容易に処理できる。これらのシリコーンオイルは１種あるいは２種以上の混合物あるいは併用や多重処理して用いられる。また、シランカップリング剤による処理と併用しても構わない。
【００９１】
このようなトナーは、種々の方法で、球形化処理、表面平滑化処理を施して用いると、転写性が良好となり好ましい。そのような方法としては、撹拌羽根またはブレードなど、およびライナーまたはケーシングなどを有する装置で、例えば、トナーをブレードとライナーの間の微小間隙を通過させる際に、機械的な力により表面を平滑化したりトナーを球形化したりする方法、温水中にトナーを懸濁させ球形化する方法、熱気流中にトナーを曝し、球形化する方法等がある。また、球状のトナーを作る方法としては、水中にトナー結着樹脂となる単量体を主成分とする混合物を懸濁させ、重合してトナー化する方法がある。一般的な方法としては、重合性単量体、着色剤、重合開始剤、さらに必要に応じて架橋剤、荷電制御剤、離型剤、その他の添加剤を均一に溶解または分散せしめて単量体組成物とした後、この単量体組成物を分散安定剤を含有する連続層、例えば水相中に適当な撹拌機を用いて適度な粒径に分散し、さらに重合反応を行わせ、所望の粒径を有する現像剤を得る方法である。
【００９２】
次に本発明の摩擦帯電付与部材が組み込まれる現像装置の例について説明する。
【００９３】
図１はキャリアを用いる二成分現像装置の一例である。現像容器２５の現像室４５内に、矢印Ｂ方向に回転される静電潜像保持体２４に対向して現像剤担持体としての非磁性現像スリーブ（現像剤担持体）２１を備え、この現像スリーブ２１内に磁界発生手段としての磁性ローラー２２が不動に設置されており、磁性ローラー２２は略頂部の位置から矢印Ａの回転方向に順にＳ１、Ｎ１、Ｓ２、Ｎ２、Ｎ３に着磁されている。現像室４５内には、トナー４０と磁性キャリア４３とを混合した二成分系現像剤４１が収容されている。この現像剤４１は、現像室４５の一端で上端開放の隔壁４８の図示しない一方の開口を通って現像容器２５の撹拌室４２内に送られると、トナー室４７から撹拌室４２内に供給されたトナー４０が補給され、撹拌室４２内の第１現像剤撹拌・搬送手段５０によって混合しながら、撹拌室４２の他端に搬送される。撹拌室４２の他端に搬送された現像剤４１は、隔壁４８の図示しない他方の開口を通って現像室４５内に戻され、そこで現像室４５内の第２現像剤撹拌・搬送手段５１と、現像室４５内上部で搬送手段５１による搬送方向と逆方向に現像剤を搬送する第３現像剤撹拌・搬送手段５２により、撹拌・搬送されながら現像スリーブ２１に搬送される。
【００９４】
現像スリーブ２１に供給された現像剤４１は、上記の磁石ローラー２２の磁力の作用により磁気的に拘束され、現像スリーブ２１上に担持され、現像スリーブ２１の略頂部上に設けた現像剤規制部材ブレード２３での規制によって現像スリーブ２１上で現像剤４１の薄層に形成されながら、現像スリーブ２１の矢印Ａ方向への回転に伴い潜像保持体２４と対向した現像部Ｃへと搬送され、そこで潜像保持体２４上の静電潜像の現像に供される。現像に消費されなかった残余の現像剤４１は、現像スリーブ２１の回転により現像容器２５内に回収される。
【００９５】
現像容器２５内では同極のＮ２、Ｎ３間での反発磁界により現像スリーブ２１上に磁気的に拘束されている現像残りの残余の現像剤４１を剥ぎ取るようになっている。上記の磁極Ｎ２により現像剤４１が磁力線に沿って穂立ちしたときのトナー飛散を防止するために、現像容器２５の下部には弾性シール部材３１がその一端を現像剤４１を接触するようにして固定、設置されている。
【００９６】
図２は、一成分磁性現像剤を用い、非接触の現像方法に用いる現像装置の一例である。公知のプロセスにより形成された静電潜像を担持する像担持体、例えば電子写真感光ドラム１は、矢印Ｂ方向に回転される。現像ローラー１２におけるスリーブ８は、ホッパー３によって供給された一成分現像剤としての磁性トナー４を担持して、矢印方向Ａ方向に回転することにより、現像スリーブ８と感光ドラム１とが対向した現像部Ｄにトナー４を搬送する。現像スリーブ８内には、磁性トナー４を現像スリーブ８上に磁気的に吸引且つ保持する為に、磁石５が配置されている。現像スリーブ８は金属円筒管６上に被覆された樹脂被覆層７を有する。ホッパー３中には磁性トナー４を撹拌するための撹拌翼１０が設けられている。
【００９７】
現像スリーブ８上の磁性トナー４の層厚を規制する部材として図２の現像装置においては磁性の金属板が現像容器３からスリーブ８表面に向かって垂下される形で取り付けられており、スリーブ表面とは一定の間隙をもって配置されている。スリーブ８とブレード２が形成する間隙は１００〜５００μｍ程度である。磁性トナー４の薄層の厚みは、現像部Ｄにおける現像スリーブ８と感光ドラム１との間の最小間隙よりも更に薄いものであることが好ましい。磁性トナー４は主として現像スリーブ８上の樹脂被覆層７との摩擦により、感光ドラム１上の静電潜像を現像可能な摩擦帯電電荷を得る。
【００９８】
上記現像スリーブ８には、これに担持された一成分磁性現像剤である磁性トナー４を飛翔させるために、電源９により現像バイアス電圧が印加される。この現像バイアス電圧として直流電圧を使用するときは、静電潜像の画像部（磁性トナー４が付着して可視化される領域）の電位と背景部の電位との間の値の電圧が、現像スリーブ８に印加されることが好ましい。一方、現像画像の濃度を高め或は階調性を向上するために、現像スリーブ８に交番バイアス電圧を印加して、現像部Ｄに向きが交互に反転する振動電界を形成してもよい。この場合、上記画像部の電位と背景部の電位の間の値を有する直流電圧成分が重畳された交番バイアス電圧を現像スリーブ８に印加することが好ましい。また高電位部と低電位部を有する静電潜像の高電位部にトナーを付着させて可視化する所謂正規現像では、静電潜像の極性と逆極性に帯電するトナーを使用し、一方、静電潜像の低電位部にトナーを付着させて可視化する所謂反転現像では、トナーは静電潜像の極性と同極性に帯電するトナーを使用する。尚、高電位、低電位というのは、絶対値による表現である。いずれにしても、磁性トナー４は現像スリーブ８との摩擦により帯電する。
【００９９】
図３においては、現像スリーブ８上の磁性トナー４の層厚を規制する部材としてはゴム弾性を有するものが用いられている。この弾性板１１を図３の現像装置では現像スリーブ８の回転方向と逆の向きで圧接させているが、順方向の向きで圧接させて用いる方法もある。このような現像装置では、図２の現像装置に比較して、現像スリーブ８上にさらに薄いトナー層を形成することができる。
【０１００】
図４には、非磁性一成分現像剤を用いた場合に用いられる現像器構成の一例を模式的に示す。本例では非磁性トナーを用いるために、金属製円筒管７６の内部には磁石は内設されていない。金属製円筒管の代わりに、円柱状部材を用いても構わない。
【０１０１】
図４の装置では、図に示されるように現像スリーブ７８表面からのトナーの剥ぎ取り部材８３が設置されている。剥ぎ取り部材としては、樹脂、ゴム、スポンジなどのローラー部材や、さらに、ベルト部材、ブラシ部材などが用いられる。図４において示したローラー状部材８３は、その接触面で現像スリーブ７８とは反対方向に回転されている。感光体７１に現像移行されなかった現像剤を、この剥ぎ取り部材８３によりいったんスリーブ表面から剥ぎ取ることにより、スリーブ上の不動のトナーの発生を防いだり、現像剤の帯電を均一化する働きを有する。図４においては、規制ブレード７２、スリーブ７６の各々の表面に樹脂被覆層７４および７７が設けられる様態が示されている。
【０１０２】
図５は、図のＥの部分で現像ロール９５が感光ドラム９１に接触していることを特徴とする。現像ロール９５は、芯金９４、弾性体９３、樹脂被覆層９２からなっている。トナー供給部材９８は、芯金９７とスポンジ状部材９６もしくはブラシ部材などからなり、現像ロール９５に接触または近接させて配置される。規制部材１０１は、弾性板９９および弾性層１００より構成されている。弾性層１００の表面に樹脂被覆層を設けてもよく、弾性板９９に直接樹脂被覆層を設けても良い。１０３は任意の撹拌部材を示す。
【０１０３】
図１〜５はあくまでも模式的な例であり、容器の形状、撹拌部材の有無、磁極の配置等に様々な形態があることは言うまでもない。
【０１０４】
【実施例】
以下、実施例をもって本発明をさらに詳しく説明する。尚、実施例及び比較例中の「％」及び「部」とあるのは、特に断りのない限り全て重量基準である。
【０１０５】
まず、本発明における第４級アンモニウム塩化合物と含窒素複素環化合物とを併用することによる作用について具体的に説明する。
【０１０６】
フェノール樹脂中間体（フェノールをＮＨ₃を触媒としてフォルムアルデヒドと共にプレポリマー化したもの）１００部のメタノール溶液に、前記の第４級アンモニウム塩化合物（１）３０部をメタノールに溶解させた後、混合して塗料（Ｘ−１）とした。
【０１０７】
さらに上記フェノール樹脂中間体１００部のメタノール溶液に、前記の第４級アンモニウム塩化合物（１）２８部をメタノールに溶解させた後、混合し、これに対し更に含窒素複素環化合物として下記式で表される個数平均粒径３μｍのイミダゾール化合物粒子（Ａ１）を２重量部添加してサンドミルにて分散を行い、塗料（ＸＹ−２）を作製した。
【０１０８】
【化１０】

【０１０９】
これと同様に下記表１に示されるように、第４級アンモニウム塩化合物（１）とイミダゾール化合物粒子（Ａ１）の混合比を変えた塗料（ＸＹ−３〜６）を作製した。また更に、上記フェノール樹脂中間体１００部のメタノール溶液に、イミダゾール化合物粒子（Ａ−１）を３０部添加してサンドミルにて分散を行い、塗料（Ｙ−７）を作製した。
【０１１０】
またイミダゾール化合物粒子の添加量を２０、１５、１０、５、２部に変化させた塗料（Ｙ−８〜１２）を作製した。
【０１１１】
これらの塗料をステンレス板にバーコーターを用いて均一膜厚に塗布し、摩擦帯電量測定用のサンプルとした。
【０１１２】
【表１】

【０１１３】
ポリエステル樹脂１００部、イエロー顔料４部、負帯電制御剤（３，５−ジターシャリーブチルサリチル酸のＣｒ錯体）４部をヘンシェルミキサーにて混合後、三本ロールで十分に混練分散し、冷却した後、１５φスクリーンのスピードミルを用いてトナー粗粉砕物を得た。この粗粉砕物の微粉を６０メッシュの振動篩いに繰り返しかけて除去した。
【０１１４】
前記サンプル板とトナー粗粉砕物を用い、図６に示すような表面帯電量測定装置（東芝ケミカル社製 ＴＳ１００ＡＳ）を用いて、摩擦帯電量の測定を行った。すなわち、トナーモデルとしての上記粗粉砕物と摩擦帯電付与部材モデルとしての表面被覆層を有するサンプル板が接触する際の摩擦帯電電荷を測定した。図の装置では、サンプル板側に発生する電荷量を測定しているが、摩擦帯電に同量の反対極性の電荷がトナー側に発生していると考えられる。
【０１１５】
結果を図７に示す。グラフからわかる様に、イミダゾール化合物粒子（Ａ１）のみを用いた塗料（Ｙ−７〜１２）では、イミダゾール化合物粒子（Ａ１）の添加量を２部としたもの（Ｙ−１２）で、既に帯電量が飽和の状態にあり、添加量を増加していっても摩擦帯電量の変化は少ない。これに対し、第４級アンモニウム塩化合物（１）とイミダゾール化合物粒子（Ａ１）の両方を用い、その添加量を変化させていった場合には、摩擦帯電量の変化が直線性を示していることがわかる。
【０１１６】
このことは即ち、本発明の方法においては、第４級アンモニウム塩化合物と含窒素複素環化合物の配合比を変化させることで、任意の摩擦帯電レベルを設定することが可能であり、且つ、添加量が多少振れたところで、その影響が出難いという製造上のメリットもある。比較サンプルとして、表２に示すようなイミダゾール化合物（正荷電制御剤）と３，５−ジターシャリーブチルサリチル酸のＣｒ錯体（負荷電制御剤）（Ｚ）を混合した系についても検討した。
【０１１７】
【表２】

【０１１８】
結果は、図７に上書きして示されるように、３，５−ジターシャリーブチルサリチル酸のＣｒ錯体（負荷電制御剤）（Ｚ）が少量添加されただけで、帯電量が低下してしまい、直線性を示さないことが判明した。
【０１１９】
＜実施例１＞
フェノール樹脂中間体（フェノールをＮＨ₃を触媒としてフォルムアルデヒドと共にプレポリマー化したもの）１００部のメタノール溶液に、前記の第４級アンモニウム塩化合物（１）１５部をメタノールに溶解させた後、混合した。これに対し、導電性カーボンブラック２５部を添加し、サンドミルにて分散した。これを塗料（Ｍ−１９）とする。さらにＭ−１９に対し、イミダゾール化合物（Ａ１）を加え分散を続けた。その後さらに個数平均粒径５μｍの球状炭素粒子２０部を加え分散させ、目的の塗料（Ｎ−２０）とした。
【０１２０】
次にこの塗料を用いて樹脂被覆層の塗工を行った。基体としては、マグネットローラー及びフランジを装着した外径２４．５ｍｍφのＳＵＳ製円筒基体を用いた。塗料の硬化後の体積抵抗値は２５Ω・ｃｍであった。塗料の固形分を３５％（塗工液粘度は３５ｍＰａ・ｓ）とした後、ワークを回転させながらスプレーガンを上下させることにより塗工し、これを熱風乾燥機にて１５０℃で６０分間乾燥硬化させ、膜厚が２０μｍの均一な導電性被覆層を形成させ、現像スリーブとした。このスリーブの表面粗さは、平均値でＲａ＝０．６（μｍ）であった。この現像スリーブを、キヤノン社製ＮＰ−６７５０の現像装置に組み込んだ。
【０１２１】
次に、磁性トナーを作製した。
【０１２２】
結着樹脂としては、ポリエステル樹脂を用いた。結着樹脂１００部に対し、アゾ系鉄錯体化合物２部、磁性酸化鉄（平均粒径０．２μｍ、Ｈ_c＝１２０エルステッド、σ_s＝７５ｅｍｕ／ｇ、σ_r＝６ｅｍｕ／ｇ）９５部、及びアルコール系ワックス５部を添加し、ヘンシェルミキサーで分散混合後、１３０℃に加熱された二軸エクストルーダーで溶融混練し、冷却した混合物をハンマーミルで粗粉砕した。粗粉砕物をジェットミルで微粉砕し、得られた微粉砕物を風力分級機で分級し、トナーの粒度分布が、重量平均粒径７．５μｍ、４μｍ以下の粒子の個数割合が１５．５％、１２．７μｍ以上の粒子の重量割合が１．０％の磁性トナーを得た。このトナーにシランカップリング剤で疎水化処理したコロイダルシリカを０．８％外添して用いた。
【０１２３】
このトナーと現像装置を用い、ＮＰ−６７５０を用いて、２３℃／５％ＲＨの常温低温（Ｎ／Ｌ）環境と、３０℃／８０％ＲＨの高温高湿（Ｈ／Ｈ）環境にて、各１０万枚までの画出し評価を行った。
【０１２４】
［評価方法］
（１）画像濃度
画像比率５．５％のテストチャート上の５ｍｍφ黒丸の濃度を、反射濃度計ＲＤ９１８（マクベス製）により反射濃度測定を行い、５点の平均値をとって画像濃度とした。
【０１２５】
（２）カブリ濃度
適性画像におけるベタ白画像の反射率を測定し、更に未使用の転写紙の反射率を測定し、（ベタ白画像の反射率の最悪値−未使用転写紙の反射率の最高値）をカブリ濃度とした。反射率はＴＣ−６ＤＳ（東京電色製）で測定した。ただし、測定値を目視で判断した場合、１．５以下は目視ではほとんど確認できないレベル、２．０〜３．０程度はよく見ると確認できるレベル、４．０を超えると一見してカブリが確認できるレベルである。
【０１２６】
（３）トナー帯電量（Ｑ／Ｍ）及びトナー搬送量（Ｍ／Ｓ）
現像スリーブ上に担持されたトナーを、金属円筒管と円筒フィルターにより吸引捕集し、その際金属円筒管を通じてコンデンサーに蓄えられた電荷量Ｑ、捕集されたトナー重量Ｍと、トナーを吸引した面積Ｓから、単位重量当たりの電荷量Ｑ／Ｍ（ｍＣ／ｋｇ）と単位面積当たりのトナー重量Ｍ／Ｓ（ｍｇ／ｃｍ²）を計算し、それぞれトナー帯電量（Ｑ／Ｍ）、トナー搬送量（Ｍ／Ｓ）とした。
【０１２７】
（４）ブロッチ（画像不良）
ベタ黒、ハーフトーン、ライン画像等の各種画像及び、その際、現像スリーブ上の波状のムラ及びブロッチ（斑点状ムラ）等、スリーブ上でのトナーコート不良の目視による観察を参考にして、評価結果を下記の指標で示した。
◎ ：画像にもスリーブ上にも全く確認できない。
○ ：スリーブ上でわずかに確認できるが、画像ではほとんど確認できない。
○△：数枚〜数十枚に１枚程度画像を透かしてみると確認できる。
△○：ハーフトーン画像又はベタ黒画像の１枚目で、スリーブ周期の１周目に確認できる。
△ ：ハーフトーン画像又はベタ黒画像で確認できる。実用レベル下限。
△×：ベタ黒画像全体で画像不良が確認できる。実用不可レベル。
× ：ベタ白画像上にも確認できる。
【０１２８】
（５）ハーフトーン均一性（白スジ、白帯）
特にハーフトーンに発生し、画像進行方向に走る、線状・帯状のスジについて、下記指標にて評価した。
◎ ：画像にもスリーブ上にも全く確認できない。
○ ：良く見るとわずかに確認できるが、一見ではほとんど確認できない。
○△：ハーフトーンではわずかに確認されるが、ベタ黒では問題ないレベル。
△○：ハーフトーンでは、スジが確認できるが、ベタ黒ではほんのわずか確認できるレベル。
△ ：ベタ黒画像でも濃淡差が確認できるが、実用レベル下限程度。
△×：ベタ黒画像全体で濃淡差が目立つ。実用不可レベル。
× ：濃度が低く、スジの多い画像。
【０１２９】
（６）スリーブゴースト
画像耐久中にベタ白を流した後、画像チャートのスリーブ一周分の白上にベタ黒の太文字や象形画像を置き、残り部分をハーフトーンとした画像チャートを用い、ハーフトーン上に太文字や象形画像のゴーストがどの程度発生するかで評価した。
◎ ：ゴーストなし。
○ ：ごくわずかに濃淡差が見られるが良好。
○△：やや濃淡差が確認できるが問題とならないレベル。
△○：○△と△の中間レベル。
△ ：ややゴーストが目立つ。実用レベル内。
Ｎ１：実用には問題となるネガゴースト（ゴースト部が薄い）がスリーブ１周分出る。
Ｐ１：実用には問題となるポジゴースト（ゴースト部が濃い）がスリーブ１周分出る。
Ｎ２：実用には問題となるネガゴーストがスリーブ２周分以上出る。
Ｐ２：実用には問題となるポジゴーストがスリーブ２周分以上出る。
【０１３０】
結果を表３及び４にまとめて示す。
【０１３１】
＜実施例２＞
イミダゾール化合物を下記（Ａ２）とした以外は、実施例１と同様にして現像スリーブを作製した。塗料の硬化後の体積抵抗値は、２８Ω・ｃｍであった（塗料Ｎ−２１）。平均の表面粗さも実施例１の現像スリーブと同様にＲａ＝０．６（μｍ）付近であった。このスリーブを用いて実施例１と同様の評価を行った。結果は、表３及び４にまとめて示す。
【０１３２】
【化１１】

【０１３３】
＜実施例３＞
イミダゾール化合物（Ａ１）の量を２０部とし、表面粗さ調整のため個数平均粒径５μｍの球状炭素粒子を２０部とした以外は、実施例１と同様にして現像スリーブを作製した。塗料の硬化後の体積抵抗値は、５８Ω・ｃｍであった（塗料Ｎ−２２）。平均の表面粗さも実施例１の現像スリーブと同様にＲａ＝０．６（μｍ）付近であった。このスリーブを用いて実施例１と同様の評価を行った。結果は、表３及び４にまとめて示す。
【０１３４】
＜実施例４＞
第４級アンモニウム塩化合物を前記（３）とし、イミダゾール化合物（Ａ１）の添加量を２０部とした以外は、実施例１と同様にして現像スリーブを作製した。塗料の硬化後の体積抵抗値は、３５Ω・ｃｍであった（塗料−２３）。このスリーブを用いて実施例１と同様の評価を行った。結果は、表３及び４にまとめて示す。
【０１３５】
＜実施例５＞
実施例１において、カーボンブラック２５部の替わりに体積平均粒径４．５μｍの結晶性グラファイト４０部、個数平均粒径５μｍの球状炭素粒子を２０部とした以外は、実施例１と同様にして現像スリーブを作製した。塗料の硬化後の体積抵抗値は、１５Ω・ｃｍであった（塗料Ｎ−２４）。平均の表面粗さは、球状炭素粒子を減らすことでＲａ＝０．６（μｍ）付近に合わせた。このスリーブを用いて実施例１と同様の評価を行った。結果は、表３及び４にまとめて示す。
【０１３６】
＜実施例６＞
結着樹脂としてナイロン樹脂を用い、ナイロン樹脂１００部に対し、第４級アンモニウム塩化合物（１）の添加量１０部、イミダゾール化合物（Ａ１）の添加量を３０部、カーボンブラックの添加量を３０部とし、それ以外は、実施例１と同様にして現像スリーブを作製した。塗料の硬化後の体積抵抗値は、６５Ω・ｃｍであった（塗料Ｎ−２５）。このスリーブを用いて実施例１と同様の評価を行った。結果は、表３及び４にまとめて示す。
【０１３７】
＜実施例７＞
結着樹脂としてポリウレタン樹脂を用い、ポリウレタン樹脂１００部に対し、第４級アンモニウム塩化合物（１）の添加量２０部、イミダゾール化合物（Ａ１）の添加量を２０部とし、それ以外は、実施例１と同様にして現像スリーブを作製した。塗料の硬化後の体積抵抗値は、３５Ω・ｃｍであった（塗料Ｎ−２６）。このスリーブを用いて実施例１と同様の評価を行った。結果は、表３及び４にまとめて示す。
【０１３８】
＜比較例１＞
実施例１のフェノール樹脂中間体１００部に、カーボンブラック２５部を加えてサンドミルにて分散し、さらに個数平均粒径５μｍの球状炭素粒子２５部を添加して分散を行い、塗料（Ｍ−２７）とした。塗料の硬化後の体積抵抗値は、１０Ω・ｃｍであった。この塗料を用いて、実施例１と同様の方法で現像スリーブを作製した。表面粗さは、ほぼＲａ＝０．６（μｍ）であった。このスリーブを用いて実施例１と同様の評価を行った。
【０１３９】
＜比較例２＞
実施例１のフェノール樹脂中間体１００部に、カーボンブラック２５部を加えてサンドミルにて分散し、さらにイミダゾール化合物（Ａ１）１５を添加し分散を続け、さらに個数平均粒径５μｍの球状炭素粒子２５部を添加して分散を行い、塗料（Ｍ−２８）とした。塗料の硬化後の体積抵抗値は、２５Ω・ｃｍであった。この塗料を用いて、実施例１と同様の方法で現像スリーブを作製した。表面粗さは、ほぼＲａ＝０．６（μｍ）であった。このスリーブを用いて実施例１と同様の評価を行った。
【０１４０】
＜比較例３＞
塗料として実施例１に示したＭ−１９を用いた。塗料の硬化後の体積抵抗値は、１８Ω・ｃｍであった。この塗料を用いて、実施例１と同様の方法で現像スリーブを作製した。表面粗さは、ほぼＲａ＝０．６（μｍ）であった。このスリーブを用いて実施例１と同様の評価を行った。
【０１４１】
＜比較例４＞
実施例１のフェノール樹脂中間体１００部に、カーボンブラック２５部を加えてサンドミルにて分散し、ここにイミダゾール化合物（Ａ１）と負荷電制御剤である３，５−ジターシャリーブチルサリチル酸のクロム錯体１５部を加えて分散し、さらに個数平均粒径５μｍの球状炭素粒子２５部を添加して分散を行い、塗料（Ｍ−２８）とした。塗料の硬化後の体積抵抗値は、２２Ω・ｃｍであった。この塗料を用いて、実施例１と同様の方法で現像スリーブを作製した。表面粗さは、ほぼＲａ＝０．６（μｍ）であった。このスリーブを用いて実施例１と同様の評価を行った。
【０１４２】
＜実施例８＞
フェノール樹脂中間体（フェノールをＮＨ₃を触媒としてフォルムアルデヒドと共にプレポリマー化したもの）１００部のメタノール溶液に、前記の第４級アンモニウム塩化合物（１）１５部をメタノールに溶解させた後、混合した。ここにイミダゾール化合物（Ａ２）の粉末２０部を加え、サンドミルを用いて分散し、塗料（Ｎ−３０）とした。
【０１４３】
平均粒径１００μｍのフェライトキャリアを芯材（コア）にして、キャリアコートを行った。Ｎ−３０を固形分濃度を１０％となるように希釈した。フェライトコア５ｋｇを小型のナウターミキサーに入れ、ジャケットを５０℃に加熱し、撹拌加温した。ここへ、Ｎ−３０を撹拌を続けながら５００ｇ滴下し、滴下終了後、温度を７０℃まで上昇させながら、メタノールを飛ばした。その後、アルミバットに排出し、恒温乾燥機を１６０℃にセットして、樹脂を加熱硬化させ、残留溶媒を飛ばした。乾燥機から出した後、撹拌しながら冷却させ、６０メッシュ篩いに通過させ、サンプルとした。
【０１４４】
次にトナーを作製した。スチレン−ブチルアクリレート−無水マレイン酸ハーフエステル共重合体１００部に対し、フタロシアニン顔料４部、低分子量ポリプロピレン２部、３，５−ジターシャリーブチルサリチル酸Ｃｒ錯体（負荷電制御剤）３部を添加し、ヘンシェルミキサーで分散混合後、１３０℃に加熱された二軸エクストルーダーで溶融混練し、冷却した混合物をハンマーミルで粗粉砕した。粗粉砕物をジェットミルで微粉砕し、得られた微粉砕物を風力分級機で分級し、トナーの粒度分布が、重量平均粒径７．０μｍ、４μｍ以下の粒子の個数割合が１３．５％、１２．７μｍ以上の粒子の重量割合が０．２％のシアン色トナーを得た。このトナーにシランカップリング剤で疎水化処理したコロイダルシリカを１．６％外添して用いた。
【０１４５】
このトナーとキヤノン社製ＮＰ−５０６０を用いて画出し評価を行った。前記キャリアと上記トナーをトナー濃度が６％となるように混合し、スタート剤（Ｄ１）を作製した。このスタート剤をＮＰ−５０６０の現像装置に充填し、トナー補給（トナー濃度調整）しながら、２万枚までの耐久を行った。２３℃／５％ＲＨの常温低温（Ｎ／Ｌ）環境と、３０℃／８０％ＲＨの高温高湿（Ｈ／Ｈ）環境にて、各２万枚までの画出し評価を行った。
【０１４６】
結果を表５及び６にまとめて示す。
【０１４７】
［評価方法］
（１）画像濃度
画像濃度は反射濃度計ＲＤ９１８（マクベス社製）で、ベタ黒（青）部の濃度を測定した。
【０１４８】
（２）トリボ
トナーとキャリアの摩擦帯電量は、図８に示すような装置で測定を行った。トナーとキャリアを、トナー濃度が６％となるように調製し、タービュラーミキサーで６０秒混合した後に測定を行った。耐久後のトリボについては現像容器中から現像剤を抜き取りさらにトナー濃度が６％になるように一部トナーもしくはキャリアを補充してから測定した。図８に示す装置において、この現像剤を低部に５００メッシュの導電性スクリーン２１３を装着した金属製の容器２１２に入れて吸引口２１７を経て吸引機２１１で吸引し、吸引前後の重量差と容器２１２に接続されたコンデンサー２１８に蓄積された電位から摩擦帯電量を求める。この際、吸引圧を２５０ｍｍＨｇとする。この方法によってトナー又はキャリアの摩擦帯電量が下記式を用いて算出される。
Ｑ（ｍＣ／ｋｇ）＝（Ｃ×Ｖ）×（Ｗ１−Ｗ２）
（式中Ｗ１は吸引前の重量であり、Ｗ２は吸引後の重量、Ｃはコンデンサーの容量、及びＶはコンデンサーに蓄積された電位である。）
【０１４９】
（３）カブリ濃度
ベタ白部の反射率を測定し、更に未使用の紙の反射率を測定し、先の値から引いてカブリ濃度とした。値は、「平均値−平均値」で示した。反射率はＴＣ−６ＤＳ（東京電色製）で測定した。
【０１５０】
（４）スリーブゴースト
ベタ画像を出した時に発生するスリーブ１周目とそれ以降の画像の濃淡差について、下記の基準にて評価した。
◎ ：濃淡差が全くない。
○ ：画像濃度には現れないが、透かしてみるとやや濃淡差がわかる程度で問題なし。
○△：画像濃度にはほとんど現れないが、見た目に濃淡差が確認できる。
△○：見た目に濃淡差がわかり、マクベスで測定して０．０１程度の反射濃度差がある。
△ ：濃淡差がやや目立つ。実用下限レベル。
△×：濃淡酸が画像濃度差にはっきり現れる。実用上問題有り。
× ：かなり濃度差があるレベル。
【０１５１】
（５）ハーフトーン均一性
ハーフトーンの均一性について下記の基準で評価した。
◎ ：均一な画像。
○ ：よく見ると若干濃淡があるが、気にならないレベル。
○△：モヤモヤ状の濃淡差がやや出ているが、スジ状は帯状の濃淡差が確認されるが、問題とはならないレベル。
△○：○△と△の中間。
△ ：モヤモヤ状の濃淡差あるいは、スジ又は帯状の濃淡差が、遠目にも確認できる。実用下限レベル。
△×：鮫肌状のモヤモヤが全体に出ているもしくは、スジがかなりはっきり確認される。
× ：濃度のあまり出ていない部分がある。
【０１５２】
＜実施例９＞
実施例８において、第４級アンモニウム塩化合物を前記の（５）を用いること以外は、実施例８と同様にしてキャリアを作製し、実施例８と同様の方法により評価を行った。結果を表５にまとめて示す（塗料Ｎ−３１）。
【０１５３】
＜比較例５＞
実施例８で用いたフェノール樹脂中間体を単独で用いてキャリアコートしたものを用いた。これを実施例８と同様の方法により評価を行った。結果を表５にまとめて示す（塗料Ｎ−３２）。
【０１５４】
＜比較例６＞
実施例８で、イミダゾール化合物（Ａ２）を添加しないもの（塗料Ｎ−３３）を用いてコートキャリアを作製し用いた。これを実施例８と同様の方法により評価を行った。結果を表５にまとめて示す。
【０１５５】
＜比較例７＞
実施例８で、第４級アンモニウム塩化合物（１）を添加せずに、イミダゾール化合物（Ａ２）をサンドミルで分散し塗料（Ｍ−３４）として用い、コートキャリアを作製した。これを実施例８と同様の方法により評価を行った。結果を表５にまとめて示す。
【０１５６】
＜実施例１０＞
ナイロン樹脂１００部のメタノール溶液に対し、第４級アンモニウム塩化合物（３）１０部をメタノールに溶解させたのち混合した。これに、イミダゾール化合物（Ａ１）３０部と体積平均粒径２．５μｍの結晶性グラファイト１０部を添加し、サンドミルを用いて十分に分散した。さらに固形分濃度を３５％に調整した（塗料Ｎ−３５）。ウレタンゴム（厚さ１ｍｍ）を幅５ｍｍにチップ状にカットし、これを台座に固定し、スプレー装置を一定方向に一定速度で移動させ、Ｎ−３５塗料を用いてスプレー塗布し、チップの長手方向３面に樹脂層を形成した。このチップを恒温乾燥機で１５０℃，２０分間乾燥させ、さらに冷却後、ブレード長さに両端を切断した。これをリン青銅（厚さ１５０μｍ）板の先端に樹脂層が形成されてない面で接着し、層厚規制ブレードとした。このブレードを、キヤノン社製ＥＰ−Ｈカートリッジに取り付けた。この際、スリーブは、下記のようなものを用いた。フェノール樹脂１００部のメタノール溶液に、平均粒径４．５μｍの結晶性グラファイト３５部と導電性カーボンブラック４部を添加し、サンドミル分散し、これをスプレーガンを用いて金属円柱（ＥＰ−Ｈ用スリーブ）に塗布し、膜厚約１０μｍの樹脂被覆層を形成した。
【０１５７】
次にトナーを作製した。スチレン−２エチルヘキシルアクリレート−アクリル酸共重合体１００部に対し、カーボンブラック５部、エステルワックス６部、アゾ系鉄錯体化合物（負荷電制御剤）３部を添加し、ヘンシェルミキサーで分散混合後、１３０℃に加熱された二軸エクストルーダーで溶融混練し、冷却した混合物をハンマーミルで粗粉砕した。粗粉砕物をジェットミルで微粉砕し、得られた微粉砕物を風力分級機で分級し、トナーの粒度分布が、重量平均粒径７．２μｍ、４μｍ以下の粒子の個数割合が１２．４％、１２．７μｍ以上の粒子の重量割合が０．３％の黒色非磁性トナーを得た。このトナーに、シランカップリング剤で疎水化処理したコロイダルシリカを１．４％外添して用いた。
【０１５８】
画出し評価は、キヤノン社製ＬＢＰ−２０３０の改造機を用いた。２３℃／５％ＲＨの常温低湿（Ｎ／Ｌ）環境と、３０℃／８０％ＲＨの高温高湿（Ｈ／Ｈ）環境にて、各５千枚までの画出し評価を行った。結果を表７及び８にまとめて示す。
【０１５９】
［評価方法］
（１）画像濃度
画像比率５．５％のテストチャート上の５ｍｍφ黒丸の濃度を、反射濃度計ＲＤ９１８（マクベス製）により反射濃度測定を行い、５点の平均値をとって画像濃度とした。
【０１６０】
（２）カブリ
適性画像におけるベタ白画像の反射率を測定し、更に未使用の転写紙の反射率を測定し、（ベタ白画像の反射率の最悪値−未使用転写紙の反射率の最高値）をカブリ濃度とした。反射率はＴＣ−６ＤＳ（東京電色製）で測定した。ここで、測定値を目視で判断した場合、１．５以下は目視ではほとんど確認できないレベル、２．０〜３．０程度はよく見ると確認できるレベル、４．０を超えると一見してカブリが確認できるレベルである。
【０１６１】
（３）トナー帯電量（Ｑ／Ｍ）及びトナー搬送量（Ｍ／Ｓ）
現像スリーブ上に担持されたトナーを、金属円筒管と円筒フィルターにより吸引捕集し、その際金属円筒管を通じてコンデンサーに蓄えられた電荷量Ｑ、捕集されたトナー重量Ｍと、トナーを吸引した面積Ｓから、単位重量当りの電荷量Ｑ／Ｍ（ｍＣ／ｋｇ）と単位面積当たりのトナー重量Ｍ／Ｓ（ｇ／ｍ²）を計算し、それぞれのトナー帯電量（Ｑ／Ｍ）、トナー搬送量（Ｍ／Ｓ）とした。
【０１６２】
（４）スリーブゴースト
ベタ画像を出した時に発生するスリーブ１周目とそれ以降の画像の濃淡差について、下記の基準にて評価した。
◎ ：濃淡差が全くない。
○ ：画像濃度には現れないが、透かしてみるとやや濃淡差がわかる程度で問題なし。
○△：画像濃度にはほとんど現れないが、見た目に濃淡差が確認できる。
△○：見た目に濃淡差がわかり、マクベスで測定して０．０１程度の反射濃度差がある。
△ ：濃淡差がやや目立つ。実用下限レベル。
△×：濃淡差が画像濃度差にはっきり現れる。実用上問題有り。
× ：かなり濃度差があるレベル。
【０１６３】
（５）ハーフトーン均一性
ハーフトーンの均一性について下記の基準で評価した。
◎ ：均一な画像。
○ ：よく見ると若干濃淡があるが、気にならないレベル。
○△：モヤモヤ状の濃淡差がやや出ているが、スジ又は帯状の濃淡差が確認されるが、問題とはならないレベル。
△○：○△と△の中間。
△ ：モヤモヤ状の濃淡差あるいは、スジ又は帯状の濃淡差が、遠目にも確認できる。実用下限レベル。
△×：鮫肌状のモヤモヤが全体に出ているもしくは、スジがかなりはっきり確認される。
× ：濃度のあまり出ていない部分がある。
【０１６４】
＜実施例１１＞
実施例１０において、イミダゾール化合物（Ａ１）の添加量を２０部とした以外は実施例１０と同様にして塗料を作製した（Ｎ−３６）。この塗料を用い、実施例１０と同様のブレードを作製し、実施例１０と同様の評価を行った。結果を表７及び８にまとめて示す。
【０１６５】
＜比較例８＞
実施例１０で用いたナイロン樹脂を単独で用いてブレードコートしたものを用いた。これを実施例１０と同様の方法にて評価を行った。結果を表７及び８にまとめて示す（塗料Ｍ−３７）。
【０１６６】
＜比較例９＞
実施例１０で、イミダゾール化合物（Ａ１）を添加しないもの（塗料Ｍ−３８）を用いてコートし、ブレードを作製し用いた。これを実施例１０と同様の方法により評価を行った。結果を表７及び８にまとめて示す。
【０１６７】
＜比較例１０＞
実施例１０で、第４級アンモニウム塩化合物（３）を添加せずに、イミダゾール化合物（Ａ１）をサンドミルで分散し塗料（Ｍ−３９）として用い、コートキャリアを作製した。これを実施例１０と同様の方法により評価を行った。結果を表７及び８にまとめて示す。
【０１６８】
【表３】

【０１６９】
【表４】

【０１７０】
【表５】

【０１７１】
【表６】

【０１７２】
【表７】

【０１７３】
【表８】

【０１７４】
【発明の効果】
以上説明したように、本発明によれば、樹脂層中の第４級アンモニウム塩化合物と含窒素複素環化合物の処方比を変化させることで、帯電量をリニアに変化させることができるため、負帯電性トナーを好適なトリボにコントロールすることのできる摩擦帯電付与部材が提供できる。また、処方比の変化に対する帯電量の変化がなだらかなため、秤量誤差程度の処方のズレでは、トナーのトリボに与える影響は小さく、生産上のラチチュードが広い。
【０１７５】
また、樹脂被覆層の強度を損なわない構成であるため、表面性が安定し、長期の画出し耐久においても、良好な画像が提供できる。
【図面の簡単な説明】
【図１】キャリアを用いる二成分現像装置の構成例を示す模式図である。
【図２】一成分磁性トナーを用いる現像装置の構成例を示す模式図である。
【図３】一成分磁性トナーを用いる現像装置の他の構成例を示す模式図である。
【図４】一成分非磁性トナーを用いる現像装置の構成例を示す模式図である。
【図５】スリーブがドラムに接触する現像方法用現像装置を模式的に示した例である。
【図６】傾斜式の表面帯電量測定装置の測定原理を示す模式図である。
【図７】本発明の樹脂被覆層の摩擦帯電特性に与える効果および比較例の摩擦帯電特性を示すグラフである。
【図８】キャリアを用いた二成分トリボを測定する装置の模式図である。
【符号の説明】
１、２４、７１、９１ 静電潜像担持体（感光ドラム）
２、１１、２３、７２、１０１ 現像剤層厚規制部材（規制ブレード）
３、２５、７３、１０２ 現像容器（ホッパー）
４、４０、４１、４３、８７ 現像剤（トナー、キャリア）
５、２２ マグネットローラー
６、７６、９４、９７、９９ 基体
７、７４、７７、９２、９３、９６ 被覆層
８、２１、７８、９５ 現像剤担持体（現像スリーブ）
９ 現像バイアス電源
１０、８０、１０３ 撹拌部材
３１ シール部材
４２、４５、４７ 撹拌室
４８ 隔壁
５０、５１、５２、９８ トナー搬送部材
Ａ 現像スリーブ回転方向
Ｂ 感光体回転方向
Ｃ、Ｄ、Ｅ 現像部[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a frictional charge imparting member for imparting a triboelectric charge to a developer (toner) used in an electrophotographic apparatus, and a developing device using the same.
[0002]
[Prior art]
Conventionally, a number of methods are known as electrophotographic methods. In general, an electro latent image is formed on an electrostatic latent image carrier (photoreceptor) by using a photoconductive substance by various means. Next, the latent image is developed with a developer (toner) to be visualized, and the toner image is transferred onto a transfer material such as paper as necessary, and then the toner image is formed on the transfer material by heat, pressure, or the like. It is fixed to obtain a copy.
[0003]
Development methods in electrophotography are mainly divided into a one-component development method and a two-component development method.
[0004]
In the two-component development method, the toner and the carrier are agitated to frictionally charge each, and the electrostatic latent image is visualized using the charged toner. Those belonging to this method are referred to as a magnetic brush method using a magnetic material such as iron powder, a cascade method using a bead carrier, a fur brush method using a fur, etc. .
[0005]
In addition, those belonging to the one-component development method include a powder cloud method in which toner particles are used in a sprayed state, a contact development method in which toner particles are directly brought into contact with an electrostatic latent image surface, and development. A jumping development method in which toner particles are caused to fly toward the latent image surface by the action of an electric field between the electrostatic latent image and the developer carrying member without directly contacting the electrostatic latent image surface, and the magnetic conductive toner is electrostatic latent image. There is a magnedry method in which development is performed in contact with the surface.
[0006]
Conventionally, fine powders in which a colorant is dispersed in a natural or synthetic resin have been used as toners applied to these development methods. For example, a dispersion in which colored particles such as various pigments, dyes, carbon black, iron oxide and the like are dispersed in a binder resin such as styrene-acrylic resin or polyester resin is made into fine particles having an average particle size of about 4 to 15 μm. Things are used as toner.
[0007]
Any toner needs to have a positive or negative charge depending on the polarity of the electrostatic latent image to be developed. As a method for holding the charge in the toner, a method utilizing the triboelectric charging property of the binder resin of the toner and a method of imparting triboelectric charging properties to various particles added to the toner are generally used. It is common to add a specific substance to be added to the toner.
[0008]
These toners usually generate a triboelectric charge by contact with various members used in the developing device. The main members are a carrier in a two-component developer, a developing sleeve, a developer layer thickness regulating blade, etc. in a one-component developer, as well as a developer supply member, an agitator, respectively. Members, conveying screws, etc. can also be involved in tribocharging.
[0009]
In general, in the development process, when trying to give a proper charge to the toner, first of all, the toner is composed of a material capable of being triboelectrically charged, that is, as described above, It is mentioned that the resin is selected from substances suitable as a resin, an additive, and a charge control agent. However, for example, the binder resin that occupies most of the toner component can play an important role not only in development but also in the fixing process, and therefore, a material that emphasizes only development (friction charging) cannot be selected. In recent years, from the viewpoint of energy saving and the like, a technique for fixing at a lower temperature or lower wattage is required, but in terms of toner, generally a binder resin having a good fixability is generally inferior in chargeability. . As an example of a method for selecting a toner material for fixing the toner with low energy, there is a method of increasing the low molecular weight component in the Tg (glass transition point) of the binder resin or the molecular weight distribution of the resin. Resins are often inferior in chargeability. In many cases, so-called waxes are added to the toner for the purpose of improving the offset resistance in the fixing process or for improving the fixing property by strengthening the plastic effect of the resin. It tends to give characteristics in a bad direction to developability.
[0010]
On the other hand, a method of adding a charge control agent to the toner to improve the triboelectric chargeability of the toner is used, but here there are various problems. For example, the charge control agent itself is easily present on the surface layer of the toner particles, but its performance tends to be exhibited. Generally, when the toner raw materials are dispersed and kneaded and then finely divided, the ratio of the surface presence to the added amount However, it is natural that a large addition amount is required to maintain a sufficient charge, but adding a large amount is likely to cause other adverse effects. For example, a pigment / dye charge control agent is liberated when the toner is made fine, and the drum, blade, developing sleeve, and other members are easily contaminated by the charge control agent contained in the toner but exposed on the toner surface. In addition, it is known that resin-based charge control agents are liable to cause deterioration of fixability and deterioration of offset resistance.
[0011]
In addition, in the toner, it is also known that a so-called charge-up phenomenon occurs due to the addition of a charge control agent or the volume resistance value of the toner is too high, and it is easy to cause a decrease in image density and image unevenness. There is difficulty in controlling the charge.
[0012]
As a second method for imparting an appropriate charge to the toner, many methods for balancing the toner charge charge by using an appropriate material for the frictional charge imparting member have been proposed.
[0013]
In general, iron powder has been used for carriers that are frictional charge imparting members used in two-component developers, but in recent years, iron as a magnetic substance has been used to adjust the charge amount of toner. In many cases, a coating material made of acrylic resin, fluororesin, silicone resin, phenol resin or the like is applied to the surface of a carrier core material using powder, ferrite, or the like.
[0014]
Further, it is known that the developer layer thickness regulating member (regulating blade) affects the frictional charging of the toner because the developer layer contacts the blade when the toner passes between the sleeve and the blade in the developing device. In the case of a one-component nonmagnetic developer, the influence is higher than that of a one-component magnetic developer. As the blade, a material such as metal or rubber is used. However, a rubber blade such as urethane rubber is often used when it is brought into elastic contact with the developer carrying member. In this case, for example, when a negatively chargeable toner is used, a nylon elastomer is used for the surface layer in contact with the toner, or when a positively charged toner is used, a silicone elastomer is used. Further, a technique for easily imparting electric charge to a toner is known, and a method of using the above triboelectric charging material by resin coating on metal or rubber is also known.
[0015]
Further, since the developing sleeve carries and conveys the developer on its surface and has many opportunities to contact with the toner, in any case, the influence on the charge of the toner is strong.
[0016]
Conventionally, a developing sleeve used in a non-contact developing device has been conventionally formed, for example, by molding a metal, an alloy thereof or a compound thereof into a cylindrical shape so that the surface thereof has a predetermined surface roughness by electrolysis, blasting, sanding, or the like. The processed one is used. However, in this case, the developer present near the surface of the developer carrier in the developer layer formed on the surface of the developer carrier by the regulating member has a very high charge, and is strongly attracted to the surface of the carrier. As a result, there is no opportunity for friction between the uncharged toner and the carrier, and this causes a so-called charge-up phenomenon in which suitable charge is not given to the developer. In such a situation, good development and transfer are not performed, and the image density is low, resulting in an image with many image unevenness and character scattering. In order to prevent the generation of such an excessively charged developer and the strong adhesion of the developer, a film in which a conductive material such as carbon black or graphite or a solid lubricant is dispersed in a resin capable of tribocharging. JP-A-1-277265 discloses a method for forming the toner on the developer carrier substrate. However, in recent years, high-definition electrophotographic images have been demanded, and the resolution of printer apparatuses has become mainstream of 600, 800, and 1200 dpi. Accordingly, a technique for increasing and stabilizing toner charge (tribo) is required. It has been. In the above disclosed method, it is possible to prevent toner charge-up and stabilize the tribo, but it is difficult to stabilize the tribo at a high level.
[0017]
In a so-called contact development method in which development is performed by directly contacting a developer carrier with a latent image carrier, an elastic body such as urethane rubber, EPDM rubber, or silicone rubber is generally attached to a main shaft of a metal such as stainless steel. Is formed on a cylinder, or is formed by forming an elastomer layer on the surface of a cylindrical member made of aluminum or stainless steel. In these cases, the so-called rubber contains impurities such as a plasticizer, a vulcanizing agent, a release agent, and a low molecular weight component, and when this comes into contact with the latent image carrier or the developer layer forming member, Bleeding adversely affects these members and images. Therefore, a layer such as a barrier layer and a protective layer is provided on the surface of the rubber layer to prevent the above-described adverse effects. Furthermore, it is also known that a surface layer is formed on the outermost surface with a material having good releasability or a resin that easily gives a frictional charge to the toner.
[0018]
Further, in order to increase the charge imparted to the toner by the surface layer of these friction charge imparting members, the binder resin has a strong friction charge imparting property, such as a silicone resin, a fluororesin, a nylon resin, a nitrogen-containing acrylic resin, etc. In addition, many techniques for further including a charge control agent and chargeable particles in the binder resin are disclosed. Further, JP-A-02-108083 discloses a developing device having a layer thickness regulating member having a resin surface containing a positive charge control agent and a negative charge control agent, and a toner conveying member.
[0019]
[Problems to be solved by the invention]
However, there are many difficult points to master such a frictional charging material. For example, the triboelectric charge amount in the material used for the toner and the charging member is almost determined by what is used for the material, and it is difficult to control to a more preferable charge level, and the level is too high or too low. Is almost. Furthermore, with regard to a system that uses a mixture of the above two types of positive and negative control agents, for example, when forming a surface layer, one of the substances is more likely to come out on the surface due to the combination, so charging as expected. It is difficult to control. Even if both are exposed, it is difficult to stably charge to a medium level because either one of the charge imparting properties wins, and the toner is charged with a bias toward the polarity of which one wins. I know that.
[0020]
Accordingly, there is a need for a technique that can be adjusted to an appropriate level in the development process using a friction charging member in accordance with the charging performance of the toner. Furthermore, there is a need for a frictional charge imparting member that has less shaving and contamination, has good durability, has a stable charge level even during long-term image output, and can stabilize image performance.
[0021]
Accordingly, an object of the present invention is to provide a method and a frictional charge imparting member capable of controlling the toner charge amount to a desirable level from the frictional charge imparting member side in accordance with the charging characteristics of the toner.
[0022]
A further object of the present invention is to provide a frictional charge imparting member that has less shaving and contamination, good durability, stable charge level even during long-term image printing, and stable image performance.
[0023]
It is a further object of the present invention to provide a stable and suitable triboelectric charge to toner in a two-component developing device using a carrier, and to prevent image density reduction due to toner charge-up and fog and image unevenness due to insufficient charge amount. And a developing device.
[0024]
Furthermore, an object of the present invention is to provide a developer layer thickness regulating member that is less likely to be scraped or contaminated even during long-term durability and can impart an appropriate triboelectric charge amount to the toner.
[0025]
A further object of the present invention is to provide a developer carrying member (sleeve) that is less likely to be scraped or contaminated even during long-term durability and can impart an appropriate triboelectric charge amount to the toner.
[0026]
It is another object of the present invention to provide a developing device that has high definition and high density even in long-term durability and does not cause fogging, streaks, or unevenness.
[0027]
[Means and Actions for Solving the Problems]
To achieve the above object, the present invention is a frictional charge imparting member used in an electrophotographic apparatus, wherein at least the surface of the frictional charge imparting member in contact with the toner is (1) a binder resin and (2) iron powder. A triboelectric charge-providing member comprising a resin coating layer formed of a resin composition having at least a quaternary ammonium salt compound positively charged with respect to (3) and a nitrogen-containing heterocyclic compound. is there.
[0028]
In the present invention, a part or all of the binder resin of the resin coating layer contains at least —NH in its molecular structure. ₂ Group, ═NH group, or —NH— bond may be included, and the nitrogen-containing heterocyclic compound in the resin coating layer is preferably an imidazole compound.
[0029]
In addition, it is more conductive in the resin coating layer. Fine particles It is also good to contain.
[0030]
The frictional charge imparting member of the present invention is most preferably a developing sleeve, a developer layer thickness regulating member, or a carrier.
[0031]
In addition, the object is to carry a latent image by carrying a developer container and a developer held in the developer container. Retention Development facing the body Part A developer carrying member for conveying the developer to the latent image Retention In the developing device that develops the latent image on the body with the developer carried and conveyed by the developer carrying member to visualize the latent image, the developing device has at least one of the above triboelectric charging members.
[0032]
Prior to the present invention, the present inventors have developed a quaternary ammonium salt compound known as a positive charge control agent of conventional toners, that is, a quaternary ammonium which is itself positively charged with respect to iron powder. As a binder resin using a salt compound, in particular, a part or all of the binder resin has at least —NH in its molecular structure. ₂ When the coating layer of the triboelectric charging member is formed using a group having any of a group, = NH group, and -NH- bond, the quaternary ammonium salt compound is taken into the binder resin, and the resin (resin layer) itself Has a strong negative chargeability and a good charge imparting property for positively chargeable toner, and a proposal that a very good image can be obtained by using it as a friction charge imparting member in a developing device. It is carried out. The advantage of this method compared to, for example, a system in which silica, fluororesin powder, and a negative charge control agent are added in order to impart positive chargeability to the toner, Since the salt compound can be dissolved and uniformly present in the resin, when the resin layer is formed, the entire resin layer becomes a uniform negatively chargeable material and is dispersed in a matrix like a silica-added system Compared to the above, it exhibits good charge imparting property, and furthermore, since it is not a powder addition system, it has good mechanical strength, that is, durability.
[0033]
Further, nitrogen-containing heterocyclic compounds are known as positively chargeable charge control agents added to the triboelectric charge imparting member for improving the triboelectric charge of negatively chargeable toners, and imidazole compounds have also been proposed. It has been confirmed that when a nitrogen-containing heterocyclic compound, particularly an imidazole compound, is dispersed in a resin layer and used as a frictional charge imparting member, the negative charge of the negatively chargeable toner is improved.
[0034]
However, as a result of various investigations by the present inventors, when these substances are added, as described above, as will be described later in Examples, the charge amount of the toner does not increase when a certain addition amount is reached. Conversely, there was a phenomenon that the effect was not obtained until a certain amount of addition was reached.
[0035]
In view of these points, as a result of various studies, a fourth ammonium salt compound known as a positive charge control agent of the conventional toner, that is, a fourth charge which is positively charged with respect to iron powder. A quaternary ammonium salt compound is used, and as a binder resin, in particular, a part or all of the binder resin has at least —NH in its molecular structure. ₂ The triboelectric charge amount of the toner is suitable by forming a coating layer of a triboelectric charge imparting member using a nitrogen-containing heterocyclic compound as a base based on a group having any of a group, ═NH group, and —NH— bond. Can be charged to a desired level, that is, by changing the addition amount and quantity ratio of the quaternary ammonium salt compound and the nitrogen-containing heterocyclic compound, the charge amount changes linearly and is suitable for triboelectric charging to the toner. The inventors have found that the level can be set, and have reached the present invention. In addition, as a comparative sample, an attempt was made to form a resin coating layer in which the addition ratio of both the positively charged nitrogen-containing heterocyclic compound and the negatively charged control agent di-tert-butylsalicylic acid Cr complex was changed. As a result, it was found that the linearity as described above could not be obtained, and the triboelectric chargeability was inclined toward the one with the superior chargeability.
[0036]
DETAILED DESCRIPTION OF THE INVENTION
As the quaternary ammonium salt compound having the above-described function which is preferably used in the present invention, those having a positive charging property with respect to iron powder are used. For example, the compound represented with the following general formula (I) is mentioned.
[0037]
[Chemical formula 5]

(R in the formula ₁ , R ₂ , R _Three And R _Four Each represents an alkyl group which may have a substituent, an aryl group which may have a substituent, and an aralkyl group, which may be the same or different. X ^- Represents an anion of an acid. )
[0038]
On the other hand, for example, a fluorine-containing quaternary ammonium salt compound having a negative chargeability with respect to iron powder as represented by the following formula (II) was also examined. It has been found that the intended purpose of the present invention is not achieved. That is, the compound represented by the following formula (II) has a strong electron-withdrawing fluororesin atom in the structure, and thus has a negative chargeability with respect to the iron powder. In addition, even when a resin composition in which the compound is dispersed in a resin is used as a coating resin, and this is heated and dried to form a coating layer on the carrier core material, the coating composition itself is positively charged with respect to the iron powder. As in the case of the present invention in which a resin containing a quaternary ammonium salt compound is used as a coating resin, high triboelectric chargeability to a positively chargeable developer was not obtained.
[0039]
[Chemical 6]

[0040]
Specific examples of the quaternary ammonium salt compound that is preferably used in the present invention and is positively charged with respect to iron powder include the following. However, it is not limited to these.
[0041]
[Chemical 7]

[0042]
The amount of the quaternary ammonium salt compound used in the present invention as described above is preferably 1 to 100 parts by weight with respect to 100 parts by weight of the coating resin. If the amount is less than 1 part by weight, the charge imparting property is not improved by addition. If the amount exceeds 100 parts by weight, the dispersion in the resin becomes poor and the film strength tends to be lowered.
[0043]
The resin used for the coating layer of the present invention is not particularly limited, but a part or all of the resin has at least —NH in its molecular structure. ₂ It preferably has any structure of a group, ═NH group, or —NH— bond. By forming the coating layer using such a resin, the effects of the present invention can be easily exhibited. In the present invention, if the resin layer of the frictional charge imparting member has a structure as described above, the obvious reason for changing itself to negative chargeability is not clear, but it is used in the present invention. A quaternary ammonium salt compound which itself is positively charged with respect to iron powder, and -NH ₂ By forming a resin coating layer using a resin having at least one structure of a group, ═NH group, or —NH— bond, a quaternary ammonium salt is incorporated into the resin structure. At that time, it is considered that the original structure of the quaternary alcohol salt having positive polarity is lost, and the chargeability of the resin incorporating these has uniform and sufficient negative chargeability.
[0044]
▲ 1 ▼ -NH ₂ As the substance having a group, R-NH ₂ Or a polyamine having them, RCO-NH ₂ As the substance having an NH group such as a first amide represented by the formula (1) or a polyamide having them, a secondary amine represented by R = NH or a polyamine having them, (RCO) ₂ Examples of the substance having (3) -NH-bond, such as a secondary amide represented by = NH or a polyamide having them, include polyurethanes having -NHCOO- bonds in addition to the polyamines and polyamides described above, An industrially synthesized resin containing one or more of the above substances or a copolymer as a copolymer is preferably used. Among these, from the viewpoint of versatility, phenol resin, polyamide resin, urethane resin and the like using ammonia as a catalyst are preferable.
[0045]
Examples of the nitrogen-containing heterocyclic compound used in the present invention include imidazole, imidazoline, imidazolone, pyrazoline, pyrazole, pyrazolone, oxazoline, oxazole, oxazolone, thiazoline, thiazole, thiazolone, selenazoline, selenazole, selenazolone, oxadiazole, thiadiazole, Tetrazole, benzimidazole, benzotriazole, benzoxazole, benzothiazole, benzoselenazole, pyrazine, pyrimidine, pyridazine, triazine, oxazine, thiazine, tetrazine, polyazaine, pyridazine, pyrimidine, pyrazine, indole, isoindole, indazole, carbazole, quinoline , Pyridine, isoquinoline, cinnoline, quinazoline, quinoxaline, phthalazine, purine, Roll, triazole, include compounds having a nitrogen-containing heterocyclic group phenazine and the like. In the present invention, an imidazole compound is particularly preferable because it promotes the effect of the interaction between the developer carrying member used in the present invention and the toner.
[0046]
In particular, among the imidazole compounds, the following general formula (1) or (2)
[0047]
[Chemical 8]

[In the formula, R ₁ And R ₂ Represents a hydrogen atom, an alkyl group, an aralkyl group or an aryl group, and R ₁ And R ₂ May be the same or different. R _Three And R _Four Represents a linear alkyl group having 3 to 30 carbon atoms, R _Three And R _Four May be the same. ]
[0048]
[Chemical 9]

[In the formula, R _Five And R ₆ Represents a hydrogen atom, an alkyl group, an aralkyl group or an aryl group, and R _Five And R ₆ May be the same. R ₇ Represents a linear alkyl group having 3 to 30 carbon atoms. ]
Is more preferable in terms of quick and uniform chargeability of the toner and strength of the coating layer.
[0049]
The reason is that the imidazole compound having the structure represented by the general formula (1) or (2) has a linear alkyl group having 3 to 30 carbon atoms as a substituent, so that the dispersibility of the coating layer with respect to the resin is improved. This is presumably because it is good and has good triboelectric charging characteristics with a toner having a dispersed state on a special surface used in the present invention.
[0050]
Further, the nitrogen-containing heterocyclic group constituting the nitrogen-containing heterocyclic compound may be monocyclic, condensed with other groups, or may be substituted.
[0051]
When this nitrogen-containing heterocyclic group is substituted, examples of the substituent include an alkyl group, an aralkyl group, an alkenyl group, an alkynyl group, an alkoxy group, an aryl group, a substituted amino group, a ureido group, a urethane group, and an aryloxy group. Group, sulfamoyl group, carbamoyl group, alkyl or arylthio group, alkyl or arylsulfonyl group, alkyl or arylsulfinyl group, hydroxy group, halogen atom, cyano group, sulfo group, aryloxycarbonyl group, acyl group, alkoxycarbonyl group, acyloxy Group, carbonamido group, sulfonamido group, carboxyl group, phosphoric acid amide group, diacylamino group, imide group and the like can be used. The above substituents may further have a substituent. As examples of the substituent, the substituents mentioned for the substituent of the nitrogen-containing heterocyclic ring can be used.
[0052]
The nitrogen-containing heterocyclic compound preferably has a number average particle diameter of preferably 20 μm or less, more preferably 0.1 to 15 μm. When the number average particle size of the nitrogen-containing heterocyclic compound exceeds 20 μm, it is not preferable because the effect of improving the charging performance is not sufficiently obtained due to poor dispersibility of the nitrogen-containing heterocyclic compound in the resin coating layer.
[0053]
As the binder resin material for the coating layer, generally known resins can be used. For example, styrene resin, vinyl resin, polyethersulfone resin, polycarbonate resin, polyphenylene oxide resin, polyamide resin, fluororesin, fiber resin, acrylic resin, epoxy resin, polyester resin, alkyd resin, phenol resin, melamine Resins, polyurethane resins, urea resins, silicone resins, polyimide resins and other thermoplastic resins, or photocurable resins can be used. Among them, those having releasability such as silicone resin and fluorine resin, or those having excellent mechanical properties such as polyethersulfone, polycarbonate, polyphenylene oxide, polyamide, phenol, polyester, polyurethane, styrene resin and acrylic resin are more. preferable.
[0054]
However, in order to easily achieve the object of the present invention, as described above, —NH ₂ It is preferable to use a binder resin having at least one structure of a group, ═NH group, or —NH— bond. Moreover, it can also be used by mixing with the above general binder resin.
[0055]
In order to adjust the volume resistance of the coating layer, the triboelectric charge imparting material of the present invention may contain other conductive fine particles dispersed in the binder resin. As such conductive fine particles, the number average particle diameter is preferably 20 μm or less, and more preferably 10 μm or less. In order to avoid the unevenness formed on the resin surface, one having a thickness of 1 μm or less is used.
[0056]
The conductive fine particles used in the present invention include carbon black such as furnace black, lamp black, thermal black, acetylene black, channel black; titanium oxide, tin oxide, zinc oxide, molybdenum oxide, potassium titanate, oxidation Examples thereof include metal oxides such as antimony and indium oxide; metals such as aluminum, copper, silver and nickel; inorganic fillers such as graphite, metal fibers and carbon fibers.
[0057]
The amount of conductive fine particles added to the coating layer described above is preferably in the range of 100 parts by weight or less with respect to 100 parts by weight of the binder resin. When the addition amount exceeds 100 parts by weight, the coating strength tends to be lowered, and the addition of a large amount of non-chargeable particles can cause a reduction in the charge amount of the toner.
[0058]
In addition, the configuration of the resin coating layer of the frictional charge imparting material of the present invention is preferable because the effect of the present invention is further promoted by dispersing a lubricating substance in the coating resin layer. Examples of the lubricating substance include graphite, molybdenum disulfide, boron nitride, mica, graphite fluoride, silver-niobium selenide, calcium chloride-graphite, talc, and fatty acid metal salts such as zinc stearate. Is preferably used because it does not impair the conductivity of the coating layer. These lubricating substances preferably have a number average particle diameter of preferably about 0.2 to 20 μm, more preferably 0.3 to 15 μm.
[0059]
As the addition amount of the lubricating substance, a particularly preferable result is given in the range of 10 to 120 parts by weight with respect to 100 parts by weight of the binder resin. When the addition amount exceeds 120 parts by weight, the coating strength tends to decrease, and when a large amount of non-chargeable additive is added, the charge amount of the toner decreases. On the other hand, if the amount is less than 10 parts by weight, it is difficult to obtain the effect of adding toner to the frictional charging member.
[0060]
Next, the configuration of the developer carrier used in the present invention will be described. The developer carrying member includes a substrate and a resin layer surrounding and covering the substrate. As the substrate, there are a cylindrical member, a columnar member, a belt-like member and the like, and a metal cylindrical tube is preferably used in a developing method which is not in contact with the drum. As the metal cylindrical tube, nonmagnetic materials such as stainless steel, aluminum and alloys thereof are preferably used. In addition, as a substrate in the developing method in which the drum is brought into direct contact, a cylindrical member having a layer structure including rubber or elastomer such as urethane, EPDM, or silicone is preferably used.
[0061]
In addition to the additive substances described above, the surface roughness is stabilized by dispersing spherical particles with a particle size of 0.3 to 30 μm in the coating resin layer as a constitution of the resin coating layer of the developer carrier. It is possible to optimize the toner coat amount on the developer carrying member. The spherical particles maintain a uniform surface roughness on the surface of the coating layer of the developer carrier, and at the same time, even when the surface of the coating layer is worn, there is little change in the surface roughness of the coating layer. There is an effect to make it difficult to wear.
[0062]
The spherical particles used in the present invention preferably have a number average particle size of 0.3 to 30 μm, more preferably 2 to 20 μm. If the number average particle diameter of the spherical particles is less than 0.3 μm, the effect of imparting uniform roughness to the surface and the effect of enhancing the charging performance are small, and the rapid and uniform charging to the developer becomes insufficient, and the coating layer This is not preferable because the toner charge up, toner contamination and toner fusion occur due to wear of the toner, and the deterioration of ghost suppression and the image density are liable to occur. When the number average particle diameter exceeds 30 μm, the surface roughness of the coating layer becomes too large, and it becomes difficult to sufficiently charge the toner, and the mechanical strength of the coating layer is decreased, which is preferable. Absent.
[0063]
More preferably, the true density of the spherical particles is 3.0 g / cm. ^Three Or less, preferably 2.7 g / cm ^Three Or less, more preferably 0.9 to 2.3 g / cm ^Three It is good to be. That is, the true density of the spherical particles is 3.0 g / cm. ^Three In the case where it exceeds 1, the dispersibility of the spherical particles in the coating layer becomes insufficient, so that it becomes difficult to impart uniform roughness to the surface of the coating layer. Also, since the storage stability of the paint is not good, it is difficult to obtain the surface of the triboelectric charge imparting member having uniform surface irregularities. The true density of the spherical particles is 0.9 g / cm ^Three Even if it is smaller, the dispersibility of the spherical particles in the coating layer becomes insufficient.
[0064]
In the present invention, the spherical shape in the spherical particles means a particle having a major axis / minor axis ratio of about 1.0 to 1.5. In the present invention, the ratio of major axis / minor axis is preferably 1. It is preferable to use particles of .0 to 1.2. When the ratio of the major axis / minor axis of the spherical particles exceeds 1.5, the coating layer surface roughness becomes non-uniform, which leads to rapid and uniform charging of the toner and the strength of the conductive coating layer. It is not preferable.
[0065]
Known spherical particles can be used as the spherical particles used in the present invention. Examples include spherical resin particles, spherical metal oxide particles, and spherical carbonized particles.
[0066]
As the spherical resin particles, for example, spherical resin particles obtained by suspension polymerization, dispersion polymerization, or the like are used. Spherical resin particles can obtain a suitable surface roughness with a smaller addition amount, and a uniform surface shape can be easily obtained. Examples of such spherical particles include acrylic resin particles such as polyacrylate and polymethacrylate, polyamide resin particles such as nylon, polyolefin resin particles such as polyethylene and polypropylene, silicone resin particles, phenol resin particles, and polyurethane resins. Resin particles, styrene resin particles, benzoguanamine particles, and the like. The resin particles obtained by the pulverization method may be used after thermally or physically spheroidizing.
[0067]
Further, an inorganic substance may be attached or fixed to the surface of the spherical particles. Such inorganic fine powders include SiO ₂ , SrTiO _Three , CeO ₂ , CrO, Al ₂ O _Three , Oxides such as ZnO and MgO, Si _Three N _Four Nitrides such as SiC, carbides such as SiC, CaSO _Four , BaSO _Four , CaCO _Three And sulfates, carbonates, and the like.
[0068]
Such inorganic fine powder may be used after being treated with a coupling agent. In particular, it can be preferably used for the purpose of improving the adhesion to the binder resin, or imparting hydrophobicity to the particles. Examples of such a coupling agent include a silane coupling agent, a titanium coupling agent, and a zircoaluminate coupling agent. More specifically, for example, as a silane coupling agent, hexamethyldisilazane, trimethylsilane, trimethylchlorosilane, trimethylethoxysilane, dimethyldichlorosilane, methyltrichlorosilane, allyldimethylchlorosilane, allylphenyldichlorosilane, Benzyldimethylchlorosilane, bromomethyldimethylchlorosilane, α-chloroethyltrichlorosilane, β-chloroethyltrichlorosilane, chloromethyldimethylchlorosilane, triorganosilylmercaptan, trimethylsilylmercaptan, triorganosilylacrylate, vinyldimethylacetoxysilane, dimethyl Diethoxysilane, dimethyldimethoxysilane, diphenyldiethoxysilane, hexamethyldisiloxane, 1,3-divinyltet Lamethyldisiloxane, 1,3-diphenyltetramethyldisiloxane and dimethylpolysiloxane containing 2 to 12 siloxane units per molecule and having hydroxyl groups bonded to one silicon atom each in the terminal unit Examples thereof include siloxane. By treating the surface of the spherical resin particles with the inorganic fine powder in this way, dispersibility in the coating layer, uniformity of the coating layer surface, stain resistance of the coating layer, chargeability to the toner, Abrasion resistance and the like can be improved.
[0069]
In addition, the spherical particles used in the present invention are preferably conductive. That is, by imparting conductivity to the spherical particles, charge is less likely to accumulate on the particle surface due to the conductivity, and toner adhesion can be reduced and toner charge imparting properties can be improved. In the present invention, the volume resistance value is 10 as the conductivity of the spherical particles. ⁶ Ω · cm or less, more preferably 10 ^-3 -10 ⁶ The particles are preferably Ω · cm.
[0070]
In the present invention, the volume resistance of the spherical particles is 10 ⁶ If it exceeds Ω · cm, toner particles are likely to be contaminated and fused with spherical particles exposed on the surface of the coating layer due to abrasion, and rapid and uniform charging is difficult to be performed.
[0071]
As a method for obtaining such conductive spherical particles, the following methods are preferable, but are not necessarily limited to these methods.
[0072]
As a method for obtaining particularly preferable conductive spherical particles used in the present invention, for example, low density and good conductive properties obtained by carbonizing and / or graphitizing by firing resin-based spherical particles and mesocarbon microbeads. The method of obtaining spherical carbon particles is mentioned. Examples of the resin used for the resin-based spherical particles include phenol resin, naphthalene resin, furan resin, xylene resin, divinylbenzene polymer, styrene-divinylbenzene copolymer, and polyacrylonitrile.
[0073]
In addition, mesocarbon microbeads can be usually produced by washing spherical crystals formed in the process of heating and firing the medium pitch with a large amount of a solvent such as tar, medium oil, and quinoline.
[0074]
More preferable methods for obtaining conductive spherical particles include phenolic resin, naphthalene resin, furan resin, xylene resin, divinylbenzene polymer, styrene-divinylbenzene copolymer, mechanochemical method on the surface of spherical resin particles such as polyacrylonitrile. And a method of obtaining conductive spherical carbon particles by coating bulk mesophase pitch by carbonization and heat-treating the coated particles in an oxidizing atmosphere, followed by firing in an inert atmosphere or vacuum to carbonize and / or graphitize. It is done. Spherical carbon particles obtained by this method are more preferred because they improve the conductivity because the crystallization of the coating of the spherical carbon particles obtained by the graphitization proceeds.
[0075]
The conductive spherical carbon particles obtained by the above-described method can control the conductivity of the spherical carbon particles obtained by changing the firing conditions in any method, and are preferably used in the present invention. . In addition, in some cases, the spherical carbon particles obtained by the above method have a true density of the conductive spherical particles of 3 g / cm in order to further increase the conductivity. ^Three The conductive metal and / or metal oxide may be plated within a range not exceeding.
[0076]
As another method for obtaining the conductive spherical particles used in the present invention, the conductive fine particles having a particle size smaller than the particle size of the core particles are mechanically mixed with the core particles made of the spherical resin particles at an appropriate blending ratio. When the conductive particles are uniformly adhered to the periphery of the core particle by the action of van der Waals force and electrostatic force, the core particle is caused by a local temperature rise caused by, for example, applying mechanical impact force. Examples thereof include a method of obtaining spherical resin particles obtained by softening the surface, forming conductive fine particles on the surface of the core particles, and conducting the conductive treatment.
[0077]
Still another method for obtaining the conductive spherical particles used in the present invention is to obtain conductive spherical particles in which the conductive fine particles are dispersed by uniformly dispersing the conductive fine particles in the spherical resin particles. Can be mentioned. As a method for uniformly dispersing the conductive fine particles in the spherical resin particles, for example, the binder resin and the conductive fine particles are kneaded to disperse the conductive fine particles, then cooled and solidified, and pulverized to a predetermined particle size. A method of obtaining spherical conductive particles by mechanical treatment and thermal treatment; or adding a polymerization initiator, conductive fine particles and other additives to the polymerizable monomer, and uniformly using a dispersing machine. The dispersed monomer composition is suspended in an aqueous phase containing a dispersion stabilizer so as to have a predetermined particle size by a stirrer or the like, polymerization is performed, and spherical particles in which conductive fine particles are dispersed are obtained. Method of obtaining.
[0078]
The core material for carriers applicable to the present invention is not particularly limited, and any conventionally known core material can be used. For example, magnetic metals such as iron, nickel, cobalt, and alloys thereof, or alloys containing rare earths, hematite, magnetite, manganese-zinc ferrite, nickel-zinc ferrite, manganese-magnesium ferrite, and lithium ferrite And the like, and iron-based oxides such as copper-zinc based ferrite, and mixtures thereof. Furthermore, ceramic particles such as glass and silicon carbide, resin powder, resin powder containing a magnetic material, and the like can be given.
[0079]
The base material for the developer layer thickness regulating member applicable to the present invention is not particularly limited, and any conventionally known base material can be used. For example, metals or alloys such as iron, stainless steel, nickel, and aluminum, and non-metallic materials such as ceramics, plastics, and rubber are often used by processing these materials into a plate shape, but in a roll shape It is also good. Further, a rubber plate may be attached to a metal base material, or an elastomer material may be attached to a portion of the metal elastic plate in contact with the sleeve.
[0080]
The method for forming the resin coating layer of the present invention is not particularly limited. For example, a coating solution containing the composition of the present invention is applied to the base material of the frictional charge imparting member by dipping, spraying, brushing, etc. If it apply | coats by this method and it is made to dry, the triboelectric charge provision member of this invention will be obtained. Further, the compound of the present invention can be dispersed and contained in a moldable resin by a known method and then molded into a sleeve, a doctor blade or the like.
[0081]
Next, the toner used in the developing device of the present invention will be described.
[0082]
The toner is a fine powder in which a resin, a release agent, a charge control agent, a colorant and the like are mainly melt-kneaded, solidified, pulverized, and then classified to obtain a uniform particle size distribution.
[0083]
As the binder resin used for the toner, generally known resins can be used. For example, styrene such as styrene, α-methylstyrene, p-chlorostyrene, and homopolymers of substitution products thereof; styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene-ethyl acrylate copolymer, styrene -Butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-dimethylaminoethyl copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer Polymer, styrene-dimethylaminoethyl methacrylate copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-maleic acid Copolymer, styrene-maleic acid Styrenic copolymer such as ter copolymer; polymethyl methacrylate, polybutyl methacrylate, polyvinyl acetate, polyethylene, polypropylene, polyvinyl butyral, polyacrylic acid resin, rosin, modified rosin, temper resin, phenolic resin, aliphatic or Alicyclic hydrocarbon resins, aromatic petroleum resins, paraffin wax, carnauba wax and the like can be used alone or in combination.
[0084]
The toner may contain a pigment. For example, carbon black, nigrosine dye, lamp black, Sudan black SM, first yellow G, benzidine yellow, pigment yellow, Indian first orange, irgadin red, paranitroaniline red, toluidine red, carmine FB, Permanent Bordeaux FRR, Pigment Orange R, Risor Red 2G, Lake Red C, Rhodamine FB, Rhodamine B Lake, Methyl Bio Red B Lake, Phthalocyanine Blue, Pigment Blue, Brilliant Green B, Phthalocyanine Green, Oil Yellow CG, Pomelo First Yellow CGG, Kaya Set Y963, Kaya Set YG, Pomelo First Orange RR, Oil Scarlet, Orazole Bra Down B, pomelo First Scarlet CG, Oil Pink OP, etc. can be applied.
[0085]
In order to use the toner as a magnetic toner, magnetic powder may be contained in the toner. As such magnetic powder, a substance that is magnetized in a magnetic field is used, and there are powders of ferromagnetic metals such as iron, cobalt, and nickel, and alloys and compounds such as magnetite, hematite, and ferrite. The content of the magnetic powder is preferably 15 to 70% by weight with respect to the toner weight.
[0086]
Waxes can be incorporated into the toner for the purpose of improving releasability during fixing and improving fixing properties. Examples of such waxes include paraffin wax and derivatives thereof, microcrystalline wax and derivatives thereof, Fischer Tropus wax and derivatives thereof, polyolefin wax and derivatives thereof, carnauba wax and derivatives thereof, and the derivatives include oxides, Includes block copolymers with vinyl monomers and graft modified products. In addition, alcohols, fatty acids, acid amides, esters, ketones, hydrogenated castor oil and derivatives thereof, plant waxes, animal waxes, mineral waxes, petrolactams, and the like can also be used.
[0087]
If necessary, the toner may contain a charge control agent. Charge control agents include negative charge control agents and positive charge control agents. For example, there are the following substances that control the toner to negative charge. For example, organometallic complexes and chelate compounds are effective, and there are monoazo metal complexes, acetylacetone metal complexes, aromatic hydroxycarboxylic acids, and aromatic dicarboxylic acid metal complexes. Other examples include aromatic hydroxycarboxylic acids, aromatic mono- and polycarboxylic acids and metal salts thereof, anhydrides, esters, and phenol derivatives such as bisphenol. Examples of substances for positively charging the toner include the following. Modified products with nigrosine and fatty acid metal salts, etc., quaternary ammonium salts such as tributylbenzylammonium-1-hydroxy-4-naphthosulfonate, tetrabutylammonium tetrafluoroborate, and oniums such as phosphonium salts which are analogs thereof Salts and lake lake pigments (including phosphotungstic acid, phosphomolybdic acid, phosphotungsten molybdic acid, tannic acid, lauric acid, gallic acid, ferricyanide, ferrocyanide) and higher fatty acid metal salts Diorganotin oxides such as dibutyltin oxide, dioctyltin oxide and dicyclohexyltin oxide; diorganotin borates such as dibutyltin borate, dioctyltin borate and dicyclohexyltin borate; guani Emissions compounds, imidazole compounds.
[0088]
The toner is used by externally adding a powder such as an inorganic fine powder as necessary for the purpose of improving fluidity. Examples of such fine powder include silica fine powder, metal oxides such as alumina, titania, germanium oxide and zirconium oxide; carbides such as silicon carbide and titanium carbide; and inorganic fine powders such as nitrides such as silicon nitride and germanium nitride. The body is used. These fine powders can be used after being organically treated with an organosilicon compound, a titanium coupling agent or the like. Examples of organosilicon compounds include hexamethyldisilazane, trimethylsilane, trimethylchlorosilane, trimethylethoxysilane, dimethyldichlorosilane, methyltrichlorosilane, allyldimethylchlorosilane, allylphenyldichlorosilane, benzyldimethylchlorosilane, bromomethyl. Dimethylchlorosilane, α-chloroethyltrichlorosilane, β-chloroethyltrichlorosilane, chloromethyldimethylchlorosilane, triorganosilylmercaptan, trimethylsilylmercaptan, triorganosilylacrylate, vinyldimethylacetoxysilane, dimethylethoxysilane, dimethyldimethoxysilane, Diphenyldiethoxysilane, hexamethyldisiloxane, 1,3-divinyltetramethyldisiloxane, Examples include 1,3-diphenyltetramethyldisiloxane, and dimethylpolysiloxane having 2 to 12 siloxane units per molecule, each containing a hydroxyl group bonded to one Si at a terminal unit. Moreover, you may use what processed the untreated fine powder with the nitrogen-containing silane coupling agent. Particularly preferred is a positively chargeable toner. Examples of such treating agents include aminopropyltrimethoxysilane, aminopropyltriethoxysilane, dimethylaminopropyltrimethoxysilane, diethylaminopropyltrimethoxysilane, dipropylaminopropyltrimethoxysilane, dibutylaminopropyltrimethoxysilane, Monobutylaminopropyltrimethoxysilane, dioctylaminopropyltrimethoxysilane, dibutylaminopropyldimethoxysilane, dibutylaminopropylmonomethoxysilane, dimethylaminophenyltrimethoxysilane, trimethoxysilyl-γ-propylphenylamine, trimethoxysilyl-γ -Propylbenzylamine, trimethoxysilyl-γ-propylpiperidine, trimethoxysilyl-γ-propylmorpholine, tri There are Tokishishiriru -γ- propyl imidazole.
[0089]
Examples of methods for treating the inorganic fine powder with the silane coupling agent include 1) spray method, 2) organic solvent method, and 3) aqueous solution method. In general, the treatment by a spray method is a method in which a pigment is stirred and an aqueous solution or solvent solution of a coupling agent is sprayed thereto, and then water or solvent is removed and dried at about 120 to 130 ° C. In addition, the treatment by the organic solvent method is to dissolve a coupling agent in an organic solvent (alcohol, benzene, halogenated hydrocarbon, etc.) containing a hydrolysis catalyst together with a small amount of water, and soak the pigment in this. Solid-liquid separation is performed by filtration or pressing and dried at about 120 to 130 ° C. The aqueous solution method is a method in which about 0.5% of a coupling agent is hydrolyzed in water or water-solvent at a constant pH, and pigment is immersed therein, followed by solid-liquid separation and drying in the same manner. is there.
[0090]
It is also possible to use fine powder treated with silicone oil as another organic treatment. As a preferable silicone oil, the viscosity at 25 ° C. is about 0.5 to 10,000 mm. ² / S, preferably 1-1000 mm ² For example, methyl hydrogen silicone oil, dimethyl silicone oil, phenyl methyl silicone oil, chlorophenyl methyl silicone oil, alkyl modified silicone oil, fatty acid modified silicone oil, polyoxyalkylene modified silicone oil, fluorine modified silicone Examples include oil. Moreover, you may use the silicone oil which has a nitrogen atom in a side chain. Particularly, a positively chargeable toner is preferable. The treatment with silicone oil can be performed, for example, as follows. If necessary, the pigment is vigorously disturbed while heating, and the silicone oil or solution thereof is sprayed or vaporized and sprayed, or the pigment is made into a slurry, and the silicone oil or its solution is stirred while stirring. It can be easily treated by dropping the solution. These silicone oils are used singly or as a mixture of two or more or in combination or multiple treatments. Moreover, you may use together with the process by a silane coupling agent.
[0091]
Such a toner is preferably used after being subjected to a spheroidizing treatment and a surface smoothing treatment by various methods. As such a method, an apparatus having a stirring blade or a blade, and a liner or a casing, for example, smoothes the surface by a mechanical force when passing the toner through a minute gap between the blade and the liner. Or a method of spheroidizing the toner, a method of suspending the toner in warm water to spheroidize, a method of exposing the toner to a hot air stream and spheroidizing. Further, as a method for producing a spherical toner, there is a method in which a mixture containing a monomer as a toner binder resin as a main component is suspended in water and polymerized to form a toner. As a general method, a polymerizable monomer, a colorant, a polymerization initiator, and, if necessary, a crosslinking agent, a charge control agent, a release agent, and other additives are uniformly dissolved or dispersed in a single amount. After making the body composition, the monomer composition is dispersed in an appropriate particle size using a suitable stirrer in a continuous layer containing a dispersion stabilizer, for example, an aqueous phase, and a polymerization reaction is further performed. This is a method for obtaining a developer having a desired particle size.
[0092]
Next, an example of a developing device in which the frictional charge imparting member of the present invention is incorporated will be described.
[0093]
FIG. 1 shows an example of a two-component developing device using a carrier. A developing chamber 45 of the developing container 25 is provided with a non-magnetic developing sleeve (developer carrying member) 21 as a developer carrying member facing the electrostatic latent image holding member 24 rotated in the arrow B direction. A magnetic roller 22 as a magnetic field generating means is fixedly installed in the sleeve 21, and the magnetic roller 22 is magnetized by S1, N1, S2, N2, and N3 in order from the substantially top position in the rotation direction of the arrow A. Yes. In the developing chamber 45, a two-component developer 41 in which the toner 40 and the magnetic carrier 43 are mixed is accommodated. When the developer 41 is fed into the stirring chamber 42 of the developing container 25 through one opening (not shown) of the partition wall 48 opened at the upper end at one end of the developing chamber 45, the developer 41 is supplied from the toner chamber 47 into the stirring chamber 42. The toner 40 is replenished and conveyed to the other end of the agitating chamber 42 while being mixed by the first developer agitating / conveying means 50 in the agitating chamber 42. The developer 41 conveyed to the other end of the agitating chamber 42 is returned to the developing chamber 45 through the other opening (not shown) of the partition wall 48, where the developer 41 and the second developer agitating / conveying means 51 in the developing chamber 45 are connected. Then, the developer is transported to the developing sleeve 21 while being stirred and transported by the third developer stirring / transporting means 52 that transports the developer in the direction opposite to the transporting direction by the transporting means 51 in the upper part of the developing chamber 45.
[0094]
The developer 41 supplied to the developing sleeve 21 is magnetically constrained by the magnetic force of the magnet roller 22 and is carried on the developing sleeve 21, and a developer regulating member provided on a substantially top portion of the developing sleeve 21. While being formed in a thin layer of the developer 41 on the developing sleeve 21 due to the restriction by the blade 23, the developing sleeve 21 is conveyed to the developing portion C facing the latent image holding member 24 as the developing sleeve 21 rotates in the direction of arrow A. Therefore, the electrostatic latent image on the latent image holding member 24 is developed. The remaining developer 41 that has not been consumed for development is collected in the developing container 25 by the rotation of the developing sleeve 21.
[0095]
In the developing container 25, the remaining developer 41 remaining after development is magnetically restrained on the developing sleeve 21 by a repulsive magnetic field between N2 and N3 of the same polarity. In order to prevent the scattering of the toner when the developer 41 rises along the lines of magnetic force due to the magnetic pole N2, the elastic seal member 31 is placed at one end of the developer container 25 at the bottom of the developing container 25. Fixed and installed.
[0096]
FIG. 2 shows an example of a developing device using a one-component magnetic developer and used in a non-contact developing method. An image carrier that carries an electrostatic latent image formed by a known process, for example, the electrophotographic photosensitive drum 1 is rotated in the direction of arrow B. The sleeve 8 in the developing roller 12 carries the magnetic toner 4 as a one-component developer supplied by the hopper 3 and rotates in the arrow direction A direction so that the developing sleeve 8 and the photosensitive drum 1 face each other. The toner 4 is conveyed to part D. A magnet 5 is disposed in the developing sleeve 8 in order to magnetically attract and hold the magnetic toner 4 on the developing sleeve 8. The developing sleeve 8 has a resin coating layer 7 coated on the metal cylindrical tube 6. A stirring blade 10 for stirring the magnetic toner 4 is provided in the hopper 3.
[0097]
As a member for regulating the layer thickness of the magnetic toner 4 on the developing sleeve 8, a magnetic metal plate is attached so as to hang down from the developing container 3 toward the surface of the sleeve 8 in the developing device of FIG. Are arranged with a certain gap. The gap formed by the sleeve 8 and the blade 2 is about 100 to 500 μm. The thickness of the thin layer of the magnetic toner 4 is preferably thinner than the minimum gap between the developing sleeve 8 and the photosensitive drum 1 in the developing portion D. The magnetic toner 4 obtains a triboelectric charge capable of developing the electrostatic latent image on the photosensitive drum 1 mainly by friction with the resin coating layer 7 on the developing sleeve 8.
[0098]
A developing bias voltage is applied to the developing sleeve 8 by a power source 9 in order to fly the magnetic toner 4 which is a one-component magnetic developer carried on the developing sleeve 8. When a DC voltage is used as the developing bias voltage, a voltage having a value between the potential of the image portion of the electrostatic latent image (the region visualized by the adhesion of the magnetic toner 4) and the potential of the background portion is developed. It is preferably applied to the sleeve 8. On the other hand, in order to increase the density of the developed image or improve the gradation, an alternating bias voltage may be applied to the developing sleeve 8 to form an oscillating electric field whose direction is alternately reversed in the developing portion D. In this case, it is preferable that an alternating bias voltage on which a DC voltage component having a value between the image portion potential and the background portion potential is superimposed is applied to the developing sleeve 8. In the so-called regular development in which the toner is attached to the high potential portion of the electrostatic latent image having a high potential portion and a low potential portion for visualization, toner charged to a polarity opposite to that of the electrostatic latent image is used, In so-called reversal development in which toner is attached to a low potential portion of an electrostatic latent image for visualization, toner that is charged with the same polarity as the polarity of the electrostatic latent image is used. The high potential and the low potential are expressed by absolute values. In any case, the magnetic toner 4 is charged by friction with the developing sleeve 8.
[0099]
In FIG. 3, a member having rubber elasticity is used as a member for regulating the layer thickness of the magnetic toner 4 on the developing sleeve 8. Although the elastic plate 11 is pressed in the direction opposite to the rotation direction of the developing sleeve 8 in the developing device of FIG. 3, there is a method in which the elastic plate 11 is pressed in the forward direction. In such a developing device, a thinner toner layer can be formed on the developing sleeve 8 as compared with the developing device of FIG.
[0100]
FIG. 4 schematically shows an example of the configuration of a developing device used when a nonmagnetic one-component developer is used. In this example, since a nonmagnetic toner is used, no magnet is provided inside the metal cylindrical tube 76. A columnar member may be used instead of the metal cylindrical tube.
[0101]
In the apparatus of FIG. 4, a toner stripping member 83 from the surface of the developing sleeve 78 is installed as shown in the drawing. As the stripping member, a roller member such as resin, rubber, or sponge, a belt member, a brush member, or the like is used. The roller-like member 83 shown in FIG. 4 is rotated in the opposite direction to the developing sleeve 78 on its contact surface. The developer that has not been transferred to the photosensitive member 71 is once peeled off from the sleeve surface by the stripping member 83, thereby preventing the generation of immobile toner on the sleeve and the function of uniformizing the charge of the developer. Have. FIG. 4 shows a state in which resin coating layers 74 and 77 are provided on the surfaces of the regulating blade 72 and the sleeve 76, respectively.
[0102]
FIG. 5 is characterized in that the developing roller 95 is in contact with the photosensitive drum 91 at a portion E in the drawing. The developing roll 95 includes a cored bar 94, an elastic body 93, and a resin coating layer 92. The toner supply member 98 includes a cored bar 97 and a sponge-like member 96 or a brush member, and is disposed in contact with or close to the developing roll 95. The restricting member 101 includes an elastic plate 99 and an elastic layer 100. A resin coating layer may be provided on the surface of the elastic layer 100, or a resin coating layer may be provided directly on the elastic plate 99. Reference numeral 103 denotes an arbitrary stirring member.
[0103]
1 to 5 are merely schematic examples, and it goes without saying that there are various forms in the shape of the container, the presence or absence of a stirring member, the arrangement of magnetic poles, and the like.
[0104]
【Example】
Hereinafter, the present invention will be described in more detail with reference to examples. In the examples and comparative examples, “%” and “parts” are based on weight unless otherwise specified.
[0105]
First, the effect | action by using together the quaternary ammonium salt compound and nitrogen-containing heterocyclic compound in this invention is demonstrated concretely.
[0106]
Phenolic resin intermediate (Phenol to NH _Three And 30 parts of the quaternary ammonium salt compound (1) in methanol and then mixed with 100 parts of a methanol solution and mixed with the paint (X-1). did.
[0107]
Furthermore, 28 parts of the quaternary ammonium salt compound (1) was dissolved in methanol in a methanol solution of 100 parts of the phenol resin intermediate, and then mixed. 2 parts by weight of the imidazole compound particles (A1) having a number average particle size of 3 μm were added and dispersed by a sand mill to prepare a paint (XY-2).
[0108]
Embedded image

[0109]
Similarly, as shown in Table 1 below, paints (XY-3 to 6) in which the mixing ratio of the quaternary ammonium salt compound (1) and the imidazole compound particles (A1) was changed were prepared. Furthermore, 30 parts of imidazole compound particles (A-1) were added to a methanol solution of 100 parts of the phenol resin intermediate and dispersed by a sand mill to prepare a paint (Y-7).
[0110]
Moreover, the coating material (Y-8-12) which changed the addition amount of the imidazole compound particle | grains into 20, 15, 10, 5, 2 parts was produced.
[0111]
These paints were applied to a stainless steel plate with a uniform thickness using a bar coater to obtain a sample for measuring the triboelectric charge.
[0112]
[Table 1]

[0113]
After mixing 100 parts of a polyester resin, 4 parts of a yellow pigment, and 4 parts of a negative charge control agent (Cr complex of 3,5-ditertiary butylsalicylic acid) with a Henschel mixer, the mixture is sufficiently kneaded and dispersed with a three roll and cooled. A coarsely pulverized toner was obtained using a 15φ screen speed mill. The coarsely pulverized fine powder was repeatedly removed through a 60-mesh vibrating sieve.
[0114]
Using the sample plate and the coarsely pulverized toner, the triboelectric charge amount was measured using a surface charge amount measuring device (TS100AS manufactured by Toshiba Chemical Corporation) as shown in FIG. That is, the triboelectric charge was measured when the coarsely pulverized product as the toner model and the sample plate having the surface coating layer as the triboelectric charge imparting member model contacted each other. In the apparatus shown in the figure, the amount of charge generated on the sample plate side is measured, but it is considered that the same amount of charge of the opposite polarity as that of frictional charging is generated on the toner side.
[0115]
The results are shown in FIG. As can be seen from the graph, in the paint (Y-7 to 12) using only the imidazole compound particles (A1), the addition amount of the imidazole compound particles (A1) is 2 parts (Y-12), and the coating is already charged. Even when the amount is saturated and the amount added is increased, the change in the triboelectric charge amount is small. On the other hand, when both the quaternary ammonium salt compound (1) and the imidazole compound particles (A1) were used and the addition amount was changed, the change in the triboelectric charge amount showed linearity. I understand that.
[0116]
This means that in the method of the present invention, an arbitrary triboelectric charge level can be set by changing the blending ratio of the quaternary ammonium salt compound and the nitrogen-containing heterocyclic compound. There is also a manufacturing merit that the effect is difficult to occur when the amount fluctuates somewhat. As a comparative sample, a system in which an imidazole compound (positive charge control agent) as shown in Table 2 and 3,5-ditertiary butylsalicylic acid Cr complex (negative charge control agent) (Z) were mixed was also examined.
[0117]
[Table 2]

[0118]
The result is overwritten in FIG. 7, and the charge amount is reduced only by adding a small amount of 3,5-ditertiary butylsalicylic acid Cr complex (negative charge control agent) (Z), It was found that it does not show linearity.
[0119]
<Example 1>
Phenolic resin intermediate (Phenol to NH _Three And 15 parts of the quaternary ammonium salt compound (1) were dissolved in methanol and then mixed with 100 parts of a methanol solution. On the other hand, 25 parts of conductive carbon black was added and dispersed with a sand mill. This is designated as paint (M-19). Further, imidazole compound (A1) was added to M-19 and dispersion was continued. Thereafter, 20 parts of spherical carbon particles having a number average particle size of 5 μm were further added and dispersed to obtain a desired paint (N-20).
[0120]
Next, the resin coating layer was applied using this paint. As the substrate, a SUS cylindrical substrate having an outer diameter of 24.5 mmφ equipped with a magnet roller and a flange was used. The volume resistance value after curing of the paint was 25 Ω · cm. After setting the solid content of the paint to 35% (coating liquid viscosity is 35 mPa · s), coating is performed by moving the spray gun up and down while rotating the workpiece, and this is dried at 150 ° C. for 60 minutes with a hot air dryer. It was cured to form a uniform conductive coating layer having a film thickness of 20 μm, and a developing sleeve was obtained. The surface roughness of this sleeve was Ra = 0.6 (μm) on average. This developing sleeve was incorporated into a developing device of Canon NP-6750.
[0121]
Next, a magnetic toner was prepared.
[0122]
A polyester resin was used as the binder resin. For 100 parts of binder resin, 2 parts of azo-based iron complex compound, magnetic iron oxide (average particle size 0.2 μm, H _c = 120 oersted, σ _s = 75 emu / g, σ _r = 6 emu / g) 95 parts and 5 parts of alcohol wax were added, dispersed and mixed with a Henschel mixer, melt kneaded with a twin screw extruder heated to 130 ° C., and the cooled mixture was coarsely pulverized with a hammer mill. . The coarsely pulverized product is finely pulverized with a jet mill, and the obtained finely pulverized product is classified with an air classifier. %, A magnetic toner having a weight ratio of particles of 12.7 μm or more of 1.0% was obtained. This toner was used with 0.8% external addition of colloidal silica hydrophobized with a silane coupling agent.
[0123]
Using this toner and developing device, NP-6750 is used in a normal temperature low temperature (N / L) environment of 23 ° C./5% RH and a high temperature high humidity (H / H) environment of 30 ° C./80% RH. Each of the images was evaluated up to 100,000 sheets.
[0124]
[Evaluation methods]
(1) Image density
The density of a 5 mmφ black circle on a test chart with an image ratio of 5.5% was measured with a reflection densitometer RD918 (manufactured by Macbeth), and an average value of five points was taken as an image density.
[0125]
(2) Fog density
Measure the reflectance of the solid white image in the aptitude image, measure the reflectance of the unused transfer paper, and fog (the worst value of the reflectance of the solid white image-the highest reflectance of the unused transfer paper). Concentration. The reflectance was measured with TC-6DS (manufactured by Tokyo Denshoku). However, when the measured value is judged visually, 1.5 or less is a level that can hardly be visually confirmed, about 2.0 to 3.0 is a level that can be confirmed by looking closely, and if it exceeds 4.0, fogging appears at a glance. It is a level that can be confirmed.
[0126]
(3) Toner charge amount (Q / M) and toner transport amount (M / S)
The toner carried on the developing sleeve is sucked and collected by a metal cylindrical tube and a cylindrical filter. At that time, the charge amount Q stored in the condenser, the collected toner weight M, and the toner are sucked through the metal cylindrical tube. From the area S, the charge amount Q / M per unit weight (mC / kg) and the toner weight M / S per unit area (mg / cm ² ) And calculated as toner charge amount (Q / M) and toner transport amount (M / S), respectively.
[0127]
(4) Blotch (defective image)
Evaluation with reference to various images such as solid black, halftone, and line images, and visual observation of defective toner coat on the sleeve such as wavy unevenness and blotch (spotted unevenness) on the developing sleeve The results are shown by the following indices.
A: Neither image nor sleeve can be confirmed at all.
○: Slightly visible on the sleeve, but hardly visible on the image.
○ △: About one to several tens of images can be confirmed by looking through the image.
Δ ○: The first halftone image or solid black image, which can be confirmed on the first round of the sleeve cycle.
Δ: Can be confirmed with a halftone image or a solid black image. Practical level lower limit.
Δ: Image defect can be confirmed in the entire solid black image. Unusable level.
×: Can be confirmed on a solid white image.
[0128]
(5) Halftone uniformity (white stripes, white belt)
In particular, the following indices were used to evaluate linear and belt-like streaks that occur in the halftone and run in the image traveling direction.
A: Neither image nor sleeve can be confirmed at all.
○: Slightly confirmed by looking closely, but hardly confirmed at first glance.
○: Slightly confirmed with halftone, but no problem with solid black.
△ ○: Levels that can be confirmed with halftones, but only slightly with solid black.
Δ: A density difference can be confirmed even in a solid black image, but it is about a practical level lower limit.
Δ ×: The density difference is conspicuous throughout the solid black image. Unusable level.
X: Image with low density and a lot of streaks.
[0129]
(6) Sleeve ghost
After flowing solid white during image endurance, place a solid black bold letter or hieroglyph image on the white for the entire circumference of the sleeve of the image chart, and use the image chart with the rest as half tone. And how much ghost image generation occurs.
A: No ghost.
○: Slight difference in density is seen but good.
○ △: A level at which a slight difference in density can be confirmed but does not cause a problem
Δ ○: Intermediate level between ○ △ and △.
Δ: A little ghost is noticeable. Within practical level.
N1: A negative ghost (ghost portion is thin), which is a problem in practical use, appears for one round of the sleeve.
P1: A positive ghost (a dark ghost portion) which is a problem in practical use appears for one turn of the sleeve.
N2: A negative ghost, which is a problem in practical use, appears over two sleeves.
P2: Positive ghost, which is a problem in practical use, appears for two or more sleeves.
[0130]
The results are summarized in Tables 3 and 4.
[0131]
<Example 2>
A developing sleeve was produced in the same manner as in Example 1 except that the imidazole compound was changed to (A2) below. The volume resistance value after curing of the paint was 28 Ω · cm (paint N-21). The average surface roughness was also about Ra = 0.6 (μm), similar to the developing sleeve of Example 1. Evaluation similar to Example 1 was performed using this sleeve. The results are summarized in Tables 3 and 4.
[0132]
Embedded image

[0133]
<Example 3>
A developing sleeve was produced in the same manner as in Example 1 except that the amount of the imidazole compound (A1) was 20 parts, and spherical carbon particles having a number average particle diameter of 5 μm were 20 parts for adjusting the surface roughness. The volume resistance value after curing of the paint was 58 Ω · cm (paint N-22). The average surface roughness was also about Ra = 0.6 (μm), similar to the developing sleeve of Example 1. Evaluation similar to Example 1 was performed using this sleeve. The results are summarized in Tables 3 and 4.
[0134]
<Example 4>
A developing sleeve was produced in the same manner as in Example 1, except that the quaternary ammonium salt compound was (3) and the amount of the imidazole compound (A1) was 20 parts. The volume resistance value after curing of the paint was 35 Ω · cm (paint 23). Evaluation similar to Example 1 was performed using this sleeve. The results are summarized in Tables 3 and 4.
[0135]
<Example 5>
In Example 1, in place of 25 parts of carbon black, 40 parts of crystalline graphite having a volume average particle diameter of 4.5 μm and 20 parts of spherical carbon particles having a number average particle diameter of 5 μm were used. A developing sleeve was prepared. The volume resistance value after curing of the paint was 15 Ω · cm (paint N-24). The average surface roughness was adjusted to around Ra = 0.6 (μm) by reducing the spherical carbon particles. Evaluation similar to Example 1 was performed using this sleeve. The results are summarized in Tables 3 and 4.
[0136]
<Example 6>
Nylon resin is used as the binder resin, and 100 parts of nylon resin is added with 10 parts of quaternary ammonium salt compound (1), 30 parts of imidazole compound (A1) is added, and 30 parts of carbon black is added. A developing sleeve was produced in the same manner as in Example 1 except for the above. The volume resistance value after curing of the paint was 65 Ω · cm (paint N-25). Evaluation similar to Example 1 was performed using this sleeve. The results are summarized in Tables 3 and 4.
[0137]
<Example 7>
A polyurethane resin is used as the binder resin. The amount of addition of the quaternary ammonium salt compound (1) is 20 parts and the amount of addition of the imidazole compound (A1) is 20 parts with respect to 100 parts of the polyurethane resin. In the same manner as in Example 1, a developing sleeve was produced. The volume resistance value after curing of the paint was 35 Ω · cm (paint N-26). Evaluation similar to Example 1 was performed using this sleeve. The results are summarized in Tables 3 and 4.
[0138]
<Comparative Example 1>
To 100 parts of the phenol resin intermediate of Example 1, 25 parts of carbon black was added and dispersed by a sand mill. Further, 25 parts of spherical carbon particles having a number average particle size of 5 μm were added and dispersed to obtain a paint (M-27 ). The volume resistance value after curing of the paint was 10 Ω · cm. Using this paint, a developing sleeve was produced in the same manner as in Example 1. The surface roughness was approximately Ra = 0.6 (μm). Evaluation similar to Example 1 was performed using this sleeve.
[0139]
<Comparative example 2>
25 parts of carbon black is added to 100 parts of the phenol resin intermediate of Example 1 and dispersed in a sand mill. Further, the imidazole compound (A1) 15 is added and the dispersion is continued, and spherical carbon particles 25 having a number average particle diameter of 5 μm are further added. Part was added and dispersed to obtain a paint (M-28). The volume resistance value after curing of the paint was 25 Ω · cm. Using this paint, a developing sleeve was produced in the same manner as in Example 1. The surface roughness was approximately Ra = 0.6 (μm). Evaluation similar to Example 1 was performed using this sleeve.
[0140]
<Comparative Example 3>
M-19 shown in Example 1 was used as a paint. The volume resistance value after curing of the paint was 18 Ω · cm. Using this paint, a developing sleeve was produced in the same manner as in Example 1. The surface roughness was approximately Ra = 0.6 (μm). Evaluation similar to Example 1 was performed using this sleeve.
[0141]
<Comparative example 4>
25 parts of carbon black was added to 100 parts of the phenol resin intermediate of Example 1 and dispersed in a sand mill, and the imidazole compound (A1) and a chromium complex of 3,5-ditertiary butylsalicylic acid as a negative charge control agent were added thereto. 15 parts were added and dispersed, and further 25 parts of spherical carbon particles having a number average particle size of 5 μm were added and dispersed to obtain a paint (M-28). The volume resistance value after curing of the paint was 22 Ω · cm. Using this paint, a developing sleeve was produced in the same manner as in Example 1. The surface roughness was approximately Ra = 0.6 (μm). Evaluation similar to Example 1 was performed using this sleeve.
[0142]
<Example 8>
Phenolic resin intermediate (Phenol to NH _Three And 15 parts of the quaternary ammonium salt compound (1) were dissolved in methanol and then mixed with 100 parts of a methanol solution. 20 parts of the powder of the imidazole compound (A2) was added thereto and dispersed using a sand mill to obtain a paint (N-30).
[0143]
Carrier coating was performed using a ferrite carrier having an average particle diameter of 100 μm as a core material (core). N-30 was diluted to a solid content concentration of 10%. 5 kg of ferrite cores were put into a small Nauter mixer, and the jacket was heated to 50 ° C. and heated with stirring. To this, 500 g of N-30 was dropped while stirring, and methanol was blown off while the temperature was raised to 70 ° C. after the dropping was completed. Then, it discharged | emitted to the aluminum bat and set the constant temperature dryer to 160 degreeC, the resin was heat-hardened, and the residual solvent was skipped. After leaving the dryer, the sample was cooled with stirring and passed through a 60 mesh sieve to obtain a sample.
[0144]
Next, a toner was prepared. To 100 parts of styrene-butyl acrylate-maleic anhydride half ester copolymer, 4 parts of phthalocyanine pigment, 2 parts of low molecular weight polypropylene, 3 parts of 3,5-ditertiary butylsalicylic acid Cr complex (negative charge control agent) are added. The mixture was dispersed and mixed with a Henschel mixer, melt-kneaded with a twin screw extruder heated to 130 ° C., and the cooled mixture was coarsely pulverized with a hammer mill. The coarsely pulverized product is finely pulverized with a jet mill, and the obtained finely pulverized product is classified with an air classifier. The particle size distribution of the toner is such that the number ratio of particles having a weight average particle size of 7.0 μm and 4 μm or less is 13.5. %, And a cyan toner having a weight ratio of particles of 12.7 μm or more is 0.2%. The toner was used with 1.6% external addition of colloidal silica hydrophobized with a silane coupling agent.
[0145]
Image evaluation was performed using this toner and NP-5060 manufactured by Canon Inc. The carrier and the toner were mixed so that the toner concentration was 6% to prepare a start agent (D1). The starter was filled in a developing device of NP-5060 and endured up to 20,000 sheets while supplying toner (adjusting toner density). Images were evaluated up to 20,000 sheets in a normal temperature low temperature (N / L) environment of 23 ° C./5% RH and a high temperature high humidity (H / H) environment of 30 ° C./80% RH.
[0146]
The results are summarized in Tables 5 and 6.
[0147]
[Evaluation methods]
(1) Image density
The image density was measured using a reflection densitometer RD918 (manufactured by Macbeth Co., Ltd.) to measure the density of the solid black (blue) part.
[0148]
(2) Tribo
The triboelectric charge amount between the toner and the carrier was measured with an apparatus as shown in FIG. The toner and the carrier were prepared so that the toner concentration was 6%, and the measurement was performed after mixing for 60 seconds with a turbuler mixer. The endurance tribo was measured after removing the developer from the developer container and replenishing part of the toner or carrier so that the toner concentration was 6%. In the apparatus shown in FIG. 8, the developer is put in a metal container 212 having a 500 mesh conductive screen 213 mounted in the lower part, and sucked by a suction device 211 through a suction port 217. The triboelectric charge amount is obtained from the potential accumulated in the capacitor 218 connected to the container 212. At this time, the suction pressure is 250 mmHg. By this method, the triboelectric charge amount of the toner or carrier is calculated using the following formula.
Q (mC / kg) = (C × V) × (W1-W2)
(W1 is the weight before suction, W2 is the weight after suction, C is the capacity of the condenser, and V is the potential accumulated in the condenser.)
[0149]
(3) fog density
The reflectance of the solid white portion was measured, and the reflectance of the unused paper was further measured and subtracted from the previous value to obtain the fog density. The value is shown as “average value−average value”. The reflectance was measured with TC-6DS (manufactured by Tokyo Denshoku).
[0150]
(4) Sleeve ghost
The following criteria were used to evaluate the difference in shading between the first round of the sleeve generated when a solid image was produced and the subsequent images.
A: There is no difference in light and shade.
○: Although it does not appear in the image density, there is no problem as far as the watermark can be seen.
◯: Almost no difference in image density, but a difference in shade can be confirmed visually.
Δ ○: A difference in light and shade is apparent, and there is a reflection density difference of about 0.01 as measured by Macbeth.
Δ: The difference in shading is slightly noticeable. Practical lower limit level.
Δ ×: Concentrated acid appears clearly in the image density difference. There is a problem in practical use.
X: Level with considerable density difference.
[0151]
(5) Halftone uniformity
Halftone uniformity was evaluated according to the following criteria.
A: Uniform image.
○: A slight contrast, but a level that does not matter.
○ △: Slightly different shades of shade, but streaks are confirmed as belt-like shades, but not problematic.
△ ○: Between △△ and △.
[Delta]: A haze-like shading difference or a streak-like or belt-like shading difference can be confirmed even at a distance. Practical lower limit level.
△ ×: Skin-like haze is appearing on the whole or streaks are confirmed quite clearly.
X: There is a part where the concentration is not so much.
[0152]
<Example 9>
In Example 8, a carrier was prepared in the same manner as in Example 8 except that the quaternary ammonium salt compound (5) was used, and evaluation was performed in the same manner as in Example 8. The results are summarized in Table 5 (Paint N-31).
[0153]
<Comparative Example 5>
The phenol resin intermediate used in Example 8 was used alone and carrier coated. This was evaluated by the same method as in Example 8. The results are summarized in Table 5 (Paint N-32).
[0154]
<Comparative Example 6>
In Example 8, a coated carrier was prepared and used without using the imidazole compound (A2) added (paint N-33). This was evaluated by the same method as in Example 8. The results are summarized in Table 5.
[0155]
<Comparative Example 7>
In Example 8, without adding the quaternary ammonium salt compound (1), the imidazole compound (A2) was dispersed with a sand mill and used as a paint (M-34) to prepare a coated carrier. This was evaluated by the same method as in Example 8. The results are summarized in Table 5.
[0156]
<Example 10>
10 parts of a quaternary ammonium salt compound (3) was dissolved in methanol and mixed with 100 parts of a nylon resin in methanol. To this, 30 parts of an imidazole compound (A1) and 10 parts of crystalline graphite having a volume average particle size of 2.5 μm were added and sufficiently dispersed using a sand mill. Furthermore, the solid content concentration was adjusted to 35% (paint N-35). Cut urethane rubber (thickness 1 mm) into a chip shape with a width of 5 mm, fix it to the base, move the spray device at a constant speed in a certain direction, spray it with N-35 paint, A resin layer was formed on three surfaces in the direction. This chip was dried at 150 ° C. for 20 minutes with a constant temperature dryer, and after cooling, both ends were cut into blade lengths. This was bonded to the tip of the phosphor bronze (thickness 150 μm) plate on the surface where the resin layer was not formed, and a layer thickness regulating blade was obtained. This blade was attached to an Canon EP-H cartridge. At this time, the following sleeve was used. To a methanol solution of 100 parts of phenol resin, 35 parts of crystalline graphite having an average particle size of 4.5 μm and 4 parts of conductive carbon black are added, dispersed in a sand mill, and this is used as a metal cylinder (for EP-H) using a spray gun. A resin coating layer having a film thickness of about 10 μm was formed.
[0157]
Next, a toner was prepared. To 100 parts of styrene-2-ethylhexyl acrylate-acrylic acid copolymer, 5 parts of carbon black, 6 parts of ester wax, 3 parts of an azo-based iron complex compound (negative charge control agent) are added and dispersed and mixed with a Henschel mixer. The mixture was melt-kneaded with a twin-screw extruder heated to 130 ° C., and the cooled mixture was coarsely pulverized with a hammer mill. The coarsely pulverized product is finely pulverized with a jet mill, and the obtained finely pulverized product is classified with an air classifier. The particle size distribution of the toner is such that the number ratio of particles having a weight average particle size of 7.2 μm and 4 μm or less is 12.4. %, A black non-magnetic toner having a weight ratio of particles of 12.7 μm or more of 0.3% was obtained. To this toner, 1.4% of colloidal silica hydrophobized with a silane coupling agent was externally used.
[0158]
For the image evaluation, a modified LBP-2030 manufactured by Canon Inc. was used. Up to 5,000 images were evaluated in a normal temperature low humidity (N / L) environment of 23 ° C./5% RH and a high temperature high humidity (H / H) environment of 30 ° C./80% RH. The results are summarized in Tables 7 and 8.
[0159]
[Evaluation methods]
(1) Image density
The density of a 5 mmφ black circle on a test chart with an image ratio of 5.5% was measured with a reflection densitometer RD918 (manufactured by Macbeth), and an average value of five points was taken as an image density.
[0160]
(2) fog
Measure the reflectance of the solid white image in the aptitude image, measure the reflectance of the unused transfer paper, and fog (the worst value of the reflectance of the solid white image-the highest reflectance of the unused transfer paper). Concentration. The reflectance was measured with TC-6DS (manufactured by Tokyo Denshoku). Here, when the measured value is judged visually, 1.5 or less is a level that can hardly be visually confirmed, about 2.0 to 3.0 is a level that can be confirmed by looking closely, and if it exceeds 4.0, it is fogged at a glance. Is a level that can be confirmed.
[0161]
(3) Toner charge amount (Q / M) and toner transport amount (M / S)
The toner carried on the developing sleeve is sucked and collected by a metal cylindrical tube and a cylindrical filter. At that time, the charge amount Q stored in the condenser, the collected toner weight M, and the toner are sucked through the metal cylindrical tube. From the area S, the charge amount per unit weight Q / M (mC / kg) and the toner weight per unit area M / S (g / m ² ) And calculated as the toner charge amount (Q / M) and the toner transport amount (M / S).
[0162]
(4) Sleeve ghost
The following criteria were used to evaluate the difference in shading between the first round of the sleeve generated when a solid image was produced and the subsequent images.
A: There is no difference in light and shade.
○: Although it does not appear in the image density, there is no problem as far as the watermark can be seen.
◯: Almost no difference in image density, but a difference in shade can be confirmed visually.
Δ ○: A difference in light and shade is apparent, and there is a reflection density difference of about 0.01 as measured by Macbeth.
Δ: The difference in shading is slightly noticeable. Practical lower limit level.
Δ: A difference in density appears clearly in the difference in image density. There is a problem in practical use.
X: Level with considerable density difference.
[0163]
(5) Halftone uniformity
Halftone uniformity was evaluated according to the following criteria.
A: Uniform image.
○: A slight contrast, but a level that does not matter.
○ △: Slightly haze-like shade difference appears slightly, but streaks or strip-like shade difference is confirmed, but does not cause a problem.
△ ○: Between △△ and △.
[Delta]: A haze-like shading difference or a streak-like or belt-like shading difference can be confirmed even at a distance. Practical lower limit level.
△ ×: Skin-like haze is appearing on the whole or streaks are confirmed quite clearly.
X: There is a part where the concentration is not so much.
[0164]
<Example 11>
In Example 10, a coating material was produced in the same manner as in Example 10 except that the addition amount of the imidazole compound (A1) was 20 parts (N-36). Using this paint, a blade similar to that in Example 10 was produced and evaluated in the same manner as in Example 10. The results are summarized in Tables 7 and 8.
[0165]
<Comparative Example 8>
The nylon resin used in Example 10 was used alone and blade-coated. This was evaluated in the same manner as in Example 10. The results are summarized in Tables 7 and 8 (Paint M-37).
[0166]
<Comparative Example 9>
In Example 10, coating was performed using a coating material (paint M-38) to which no imidazole compound (A1) was added, and a blade was prepared and used. This was evaluated by the same method as in Example 10. The results are summarized in Tables 7 and 8.
[0167]
<Comparative Example 10>
In Example 10, without adding the quaternary ammonium salt compound (3), the imidazole compound (A1) was dispersed with a sand mill and used as a coating material (M-39) to prepare a coated carrier. This was evaluated by the same method as in Example 10. The results are summarized in Tables 7 and 8.
[0168]
[Table 3]

[0169]
[Table 4]

[0170]
[Table 5]

[0171]
[Table 6]

[0172]
[Table 7]

[0173]
[Table 8]

[0174]
【The invention's effect】
As described above, according to the present invention, the charge amount can be changed linearly by changing the prescription ratio of the quaternary ammonium salt compound and the nitrogen-containing heterocyclic compound in the resin layer. It is possible to provide a triboelectric charging member capable of controlling the chargeable toner to a suitable tribo. In addition, since the change in the charge amount with respect to the change in the prescription ratio is gentle, the deviation of the prescription with the weighing error has little effect on the toner tribo, and the production latitude is wide.
[0175]
Moreover, since the structure does not impair the strength of the resin coating layer, the surface property is stable, and a good image can be provided even in long-term image output durability.
[Brief description of the drawings]
FIG. 1 is a schematic diagram illustrating a configuration example of a two-component developing device using a carrier.
FIG. 2 is a schematic diagram illustrating a configuration example of a developing device using a one-component magnetic toner.
FIG. 3 is a schematic diagram illustrating another configuration example of a developing device using a one-component magnetic toner.
FIG. 4 is a schematic diagram illustrating a configuration example of a developing device using a one-component nonmagnetic toner.
FIG. 5 is an example schematically showing a developing device for a developing method in which a sleeve contacts a drum.
FIG. 6 is a schematic diagram showing a measurement principle of an inclined surface charge amount measuring apparatus.
FIG. 7 is a graph showing the effect of the resin coating layer of the present invention on the triboelectric charge characteristic and the triboelectric charge characteristic of a comparative example.
FIG. 8 is a schematic diagram of an apparatus for measuring a two-component tribo using a carrier.
[Explanation of symbols]
1, 24, 71, 91 Electrostatic latent image carrier (photosensitive drum)
2, 11, 23, 72, 101 Developer layer thickness regulating member (regulating blade)
3, 25, 73, 102 Developer container (hopper)
4, 40, 41, 43, 87 Developer (toner, carrier)
5, 22 Magnet roller
6, 76, 94, 97, 99 substrate
7, 74, 77, 92, 93, 96 Coating layer
8, 21, 78, 95 Developer carrier (developing sleeve)
9 Development bias power supply
10, 80, 103 Stirring member
31 Seal member
42, 45, 47 Mixing chamber
48 Bulkhead
50, 51, 52, 98 Toner conveying member
A Development sleeve rotation direction
B Photoconductor rotation direction
C, D, E Development part

Claims (16)

In the frictional charge imparting member used in the electrophotographic apparatus, at least the surface of the frictional charge imparting member that comes into contact with the toner is (1) a quaternary ammonium that is positively charged with respect to the binder resin and (2) iron powder. A frictional charge imparting member having a resin coating layer formed of a resin composition having at least a salt compound and (3) a nitrogen-containing heterocyclic compound. The part or all of the binder resin of the resin coating layer has at least one of —NH ₂ group, ═NH group, and —NH— bond in its molecular structure. Friction charging member. The frictional charge imparting member according to claim 1 or 2, wherein the nitrogen-containing heterocyclic compound in the resin coating layer is an imidazole compound. The imidazole compound is represented by the following formula (1) or (2)

[Wherein, R ₁ and R ₂ represent a hydrogen atom, an alkyl group, an aralkyl group or an aryl group, and R ₁ and R ₂ may be the same or different. R ₃ and R ₄ represent a linear alkyl group having 3 to 30 carbon atoms, and R ₃ and R ₄ may be the same. ]

[Wherein, R ₅ and R ₆ represent a hydrogen atom, an alkyl group, an aralkyl group or an aryl group, and R ₅ and R ₆ may be the same. R ₇ represents a linear alkyl group having 3 to 30 carbon atoms. ]
The triboelectric charge imparting member according to claim 3, wherein the triboelectric charge imparting member is a compound represented by the formula: The frictional charge imparting member according to claim 1, wherein the resin coating layer further contains conductive fine particles . The frictional charge imparting member according to any one of claims 1 to 5, wherein the frictional charge imparting member is a developer carrier. 6. The friction charge imparting member according to claim 1, wherein the friction charge imparting member is a developer layer thickness regulating member. 6. The friction charge imparting member according to claim 1, wherein the friction charge imparting member is a carrier particle. Has a developing container, a developer carrying member for conveying to the developing unit facing the developer carrying the latent image holding member having the retained toner to the developing container a developer, the latent image bearing member on A developing device that develops the latent image of the toner with a toner charged by friction with a frictional charge imparting member of the developer carried and conveyed by the developer carrier and visualizes the latent image;
At least the surface in contact with the toner of the triboelectric charging member has (1) a binder resin, (2) a quaternary ammonium salt compound that is positively charged with respect to iron powder, and (3) a nitrogen-containing heterocyclic compound. A developing device comprising a resin coating layer formed of a resin composition having at least The part or all of the binder resin of the resin coating layer has at least one of —NH ₂ group, ═NH group, and —NH— bond in its molecular structure. Development device. The developing device according to claim 9 or 10, wherein the nitrogen-containing heterocyclic compound in the resin coating layer is an imidazole compound. The imidazole compound is represented by the following formula (1) or (2)

[Wherein, R ₁ and R ₂ represent a hydrogen atom, an alkyl group, an aralkyl group or an aryl group, and R ₁ and R ₂ may be the same or different. R ₃ and R ₄ represent a linear alkyl group having 3 to 30 carbon atoms, and R ₃ and R ₄ may be the same. ]

[Wherein, R ₅ and R ₆ represent a hydrogen atom, an alkyl group, an aralkyl group or an aryl group, and R ₅ and R ₆ may be the same. R ₇ represents a linear alkyl group having 3 to 30 carbon atoms. ]
The developing device according to claim 11 , wherein the developing device is a compound represented by the formula: The developing device according to claim 9, wherein the resin coating layer further contains conductive fine particles . The developing device according to claim 9, wherein the frictional charging member is a developer carrying member. The developing device according to claim 9, wherein the frictional charge imparting member is a developer layer thickness regulating member. The developing device according to claim 9, wherein the frictional charging member is carrier particles.

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