JP4149242B2 - Conductive polymer composition and method for producing the same - Google Patents

Description

【００２６】
【化２】

【００２７】
上述した理由により、フルオロ基及びスルホニル基を有する陰イオンを備えた塩は、ビス（トリフルオロメタンスルホニル）イミドのアルカリ金属塩、トリス（トリフルオロメタンスルホニル）メチドのアルカリ金属塩、トリフルオロメタンスルホン酸のアルカリ金属塩からなる群の内の少なくとも１つから選ばれた塩であるのが最適である。
【００２８】
陰イオンがビス（フルオロアルキルスルホニル）イミドイオン、トリス（フルオロアルキルスルホニル）メチドイオンからなる塩、特には、ビス（トリフルオロメタンスルホニル）イミドリチウムは、非常に高温に渡っても安定なため、従来、用いられていた過塩素酸リチウムや過塩素酸第４級アンモニウム塩等と異なり、防爆仕様にする等の処置が不要である。この点からも、製造コストを減じたり、安全性を確保したりでき、非常に優れている。
【００２９】
陽イオンと陰イオンに解離可能な塩は、数平均分子量（Ｍｎ）１万以下の低分子量ポリエーテル化合物や低分子量極性化合物である導電性可塑剤からなる媒体を介さずに配合されていることが好ましい。このような媒体を用いると、長時間連続して用いた場合に電気抵抗値が大きく上昇したり、媒体がイオンとともに析出し、感光体汚染を起こしやすくなったりする場合がある。
上記した媒体を介さずに、解離可能な塩を配合する方法は、公知の手法を用いることが出来る。例えば、ヘンシェルミキサー、タンブラー等でドライブレンドを行った後、解離可能な塩とポリマーを含むブレンド物を、単軸または二軸押出機、バンバリーミキサー、ニーダー等で溶融混合を行う等の方法を用いることが出来る。この他、熱可塑性樹脂や熱可塑性エラストマーのポリマー系で、解離可能な塩を高温で配合する場合、ポリマーの劣化を防ぐ等の目的で、必要に応じて、窒素などの不活性ガス雰囲気下で配合（混合）を行うことも出来る。
【００３０】
本発明の導電性ポリマー組成物は、適度な弾性等を付与できるため、加硫ゴム組成物としている。
【００３１】
上記陽イオンと陰イオンに解離可能な塩を偏在させた第１非連続相を構成するポリマーは、エーテル結合により、かかる塩から生じる陽イオンを強く安定化できることから、塩とポリマーとの親和性を高く出来るという理由により、ポリオキシアルキレン系共重合体あるいはエピハロヒドリン系ポリマーとしている。なお、第２の発明における非連続相（第１非連続相）を構成するポリマーはポリオキシアルキレン系共重合体としている。
このように、第１非連続相を構成するポリマーと塩との親和性を高くすることにより、組成物全体の抵抗値を効果的に下げることが出来ると共に、塩の系外への析出や連続使用時の抵抗値の上昇を防ぐことができる。
具体的には、上記第１非連続相を構成するポリマーとしては、エチレンオキサイド−プロピレンオキサイド−アリルグリシジルエーテル共重合体（ＥＯ−ＰＯ−ＡＧＥ共重合体）あるいは／及びエピクロルヒドリンゴムを用いることが好ましい。エピクロルヒドリンゴムとしては、エピクロルヒドリン−エチレンオキサイド共重合体、エピクロルヒドリン−エチレンオキサイド−アリルグリシジルエーテル共重合体、エピクロルヒドリン−エチレンオキサイド−プロピレンオキサイド−アリルグリシジルエーテル共重合体、エピクロルヒドリン−エチレンオキサイド−プロピレンオキサイド共重合体、エピクロルヒドリン−アリルグリシジルエーテル共重合体等が挙げられる。
この他、ポリエチレンオキサイドブロックポリアミド共重合体、ポリエーテルエステルアミド共重合体も、本発明で用いられる塩との親和性が大きく、第１非連続相を構成するポリマーとして好適に用いられる。
【００３２】
上記ＥＯ−ＰＯ−ＡＧＥ共重合体を用いた場合、組成物の物性（圧縮永久ひずみ、硬度）を維持しながら、体積抵抗率を低減できるように共重合比率を設定することができる。共重合体中、エチレンオキサイド比率は５５モル％以上９５モル％以下であるのが好ましい。イオン導電性が発揮されるのは、ポリマー中のオキソニウムイオンや金属陽イオン等（例えば、添加した塩中のリチウムイオン等の陽イオン等）が、エチレンオキサイドユニットやプロピレンオキサイドユニットで安定化され、その部分の分子鎖のセグメント運動により運搬されることによる。尚、一般には、エチレンオキサイドユニットの方がプロピレンオキサイドユニットよりも上記安定性が高い。よって、エチレンオキサイドユニットの比率が高い方が多くのイオンを安定化でき、より低抵抗化を実現できる。
【００３３】
上記連続相を構成するポリマーはアクリロニトリルブタジエンゴム（ＮＢＲ）としており、なかでも、低ニトリルＮＢＲあるいは／及び中高ニトリルＮＢＲ、または、ポリエステル系熱可塑性エラストマーとしていることが好ましい。これにより、全体として極力低い抵抗値とすることができる上に、解離可能な塩の組成物外への移行や連続通電時の抵抗上昇を防ぐことができる。なお、連続相の材料としては、ある程度電気抵抗値が低く、かつ、Ｔｇが低いため室温付近での粘弾性の温度依存性が小さく、それによって体積抵抗率の環境依存性を小さくすることの出来る、低ニトリルＮＢＲ等が特に好ましい。また、これらのポリマーのＴｇとしては、−４０℃以下、より好ましくはー５０℃以下である。
【００３４】
陽イオンと陰イオンに解離可能な塩を偏在させない上記第２非連続相は、低極性ゴムであるエチレンプロピレンジエン共重合ゴム（ＥＰＤＭ）としている。これにより、組成物に耐オゾン性を付与することができる。例えば、画像形成装置に用いられる導電性部材等に用いた場合でも、装置内に生じるオゾンに対して、耐オゾン性を確保することができる。
さらに、系全体の室温付近での粘弾性の温度依存性を小さくして、電気抵抗値の環境依存性を小さくするために、連続相に用いるポリマーだけでなく、第２非連続相に用いるポリマーも、よりＴｇの低いものが好ましい。これは第１非連続相に用いるポリマーについても同様である。尚、これらのポリマーのＴｇとしては−４０℃以下であることが好ましく、さらにはー５０℃以下であることがより好ましい。
【００３５】
本発明では、添加する塩から生じるイオンの一部を、陰イオン吸着剤等を用いてシングルイオン化し、導電性の安定や、少量添加時の導電性向上をはかることができる。陰イオン吸着剤としては、ＭｇとＡｌを主成分とする合成ハイドロタルサイト、Ｍｇ−Ａｌ系，Ｓｂ系，Ｃａ系等の無機イオン交換体やアニオンを連鎖中に固定するイオン席を有する（共）重合体等の公知の化合物が有用である。具体的には、合成ハイドロタルサイト（協和化学工業（株）製、商品名キョーワード２０００、キョーワード１０００）、アニオン交換性イオン交換樹脂（日本錬水（株）製、商品名ダイアノンＤＣＡ１１）等が挙げられる。
【００３６】
ポリマーとして塩素等のハロゲンを含むポリマーを使用する場合、ポリマーの脱塩化水素反応による劣化や、混練機が錆びるのを防ぐため、ハイドロタルサイト等の受酸剤を配合することが好ましい。配合量としては、合成ハイドロタルサイトの場合、ハロゲン含有ポリマー１００重量部に対して、１重量部以上１５重量部以下、好ましくは３重量部以上１２重量部以下とすると良い。
【００３７】
添加する加硫剤としては、特に、低電気抵抗を実現できるため、硫黄が好ましい。また、硫黄、有機含硫黄化合物の他、過酸化物なども使用可能であり、これらを併用することもできる。特に、ＥＰＤＭ、ＥＰＭを上記第２非連続相を形成する低極性ゴムとして用いた場合、過酸化物によれば、これらのゴムからなる相を効果的に加硫することができる。
有機含硫黄化合物としては、例えば、テトラエチルチウラムジスルフィド、Ｎ，Ｎ−ジチオビスモルホリンなどが挙げられる。過酸化物としてはジクミルペルオキシド、ベンゾイルペルオキシド等を挙げることができる。なお、これらのうち、加硫とともに発泡を行う場合には、加硫速度と発泡速度のバランスが良くなる点から硫黄を用いるのが好ましい。加硫剤の添加量は、ポリマー成分１００重量部に対して、０．５重量部以上５重量部以下、好ましくは１重量部以上３重量部以下がよい。
【００３８】
また、加硫促進剤を配合してもよく、消石灰、マグネシア（ＭｇＯ）、リサージ（ＰｂＯ）等の無機促進剤や以下に記す有機促進剤を用いることができる。
有機促進剤としては、２−メルカプト・ベンゾチアゾール、ジベンゾチアジルジスルフィド等のチアゾール系、Ｎ−シクロヘキシル−２−ベンゾチアジルスルフェンアミド等のスルフェンアミド系、テトラメチルチウラムモノスルフィド、テトラメチルチウラムジスルフィド、テトラエチルチウラムジスルフィド、ジペンタメチレンチウラムテトラスルフィド等のチウラム系、チオウレア系等を適宜組み合わせて用いることができる。
また、加硫促進剤は、ポリマー成分１００重量部に対して、１重量部以上５重量部以下、さらには２重量部以上４重量部以下が好ましい。
【００３９】
また、加硫促進助剤を配合しても良く、例えば亜鉛華等の金属酸化物、ステアリン酸、オレイン酸、綿実脂肪酸等の脂肪酸、その他従来公知の加硫促進助剤が挙げられる。
柔軟性等の付与のためポリマー成分１００重量部に対して、化学発泡剤を３重量部以上１２重量部以下の割合で配合しても良い。その他、オイル等の軟化剤、老化防止剤等を配合しても良い。
また、機械的強度を向上させる等の目的のために、電気特性や他の物性を損なわない範囲で必要に応じて充填剤を配合することができる。充填剤としては、例えば、シリカ、カーボンブラック、クレー、タルク、炭酸カルシウム、炭酸マグネシウム、水酸化アルミニウム等の粉体を挙げることができる。充填剤はポリマー１００重量部に対し６０重量部以下とするのが良い。
【００４０】
なお、本発明の導電性ポリマー組成物は、塩素あるいは臭素を有する塩を用いないで、非塩素系、非臭素系とすると、より好ましい。
具体的には、ポリマーとして塩素・臭素を含まない材料を用いると共に、過塩素酸リチウム、過塩素酸ナトリウムあるいは過塩素酸第４級アンモニウム塩等の塩素・臭素を含む塩を用いず、組成物全体として非塩素、非臭素系の組成物とすることで、導電性ローラのシャフト等の金属表面を腐食したり、発錆させたり、あるいは汚染したりする恐れがなくなる。さらに、使用後の焼却処理等も非常に行いやすく、環境に優しい組成物とすることができる。
【００４１】
上記した本発明の導電性ポリマー組成物は、ＪＩＳ Ｋ６２６２に記載の加硫ゴム及び熱可塑性ゴムの永久ひずみ試験法において、測定温度７０℃、測定時間２２〜２４時間、圧縮率２５％で測定した圧縮永久ひずみの大きさが３０％以下であることが好ましい。これは、３０％より大きいと、上記組成物を成形してローラやベルト等の導電性部材として使用した時に寸法変化が大きくなりすぎて実用に適さないためである。なお、より好ましくは２５％以下であり、小さければ小さいほど良い。
【００４２】
また、印加電圧１００Ｖのもとで測定したＪＩＳ Ｋ６９１１に記載の体積抵抗率が１０^10.0［Ω・ｃｍ］未満であるのが好ましい。これは、体積抵抗率が１０^10.0Ωｃｍより大きいと、導電性部材等とした際に、良好な導電性が得られず、実用に適さなくなるためである。また、該組成物を成形してローラやベルト等とした際に転写や帯電、トナー供給等の効率が低下しやすいためである。なお、体積抵抗率は、１０^4.0Ωｃｍ以上１０^9.5Ωｃｍ以下であるのがより好ましい。
【００４３】
さらに、２３℃、相対湿度５５％の環境下で、厚みが０．２５ｍｍのサンプルに対し１０００Ｖの定電圧を５時間連続印加した場合の体積抵抗率ρ_Ｖ［Ω・ｃｍ］を測定し、体積抵抗率の上昇量Δｌｏｇ₁₀ρ_Ｖ＝ｌｏｇ₁₀ρ_Ｖ（ｔ＝５ｈｒ．）−ｌｏｇ₁₀ρ_Ｖ（ｔ＝０ｈｒ．）の値を０．５以下としているのが好ましい。これは、上記体積抵抗率の上昇量の指標値が０．５より大きいと導電性部材等に成形した場合に、連続使用時の抵抗上昇が大きくなり、実用に支障をきたす恐れが生じるためである。
【００４４】
さらに、１０℃相対湿度１５％、３２．５℃相対湿度９０％の条件下での体積抵抗率ρ_Ｖ［Ω・ｃｍ］を測定し、体積抵抗率の環境依存性Δｌｏｇ₁₀ρ_Ｖ＝ｌｏｇ₁₀ρ_Ｖ（１０℃相対湿度１５％）−ｌｏｇ₁₀ρ_Ｖ（３２．５℃相対湿度９０％）の値を１．７以下、好ましくは１．４以下、より好ましくは１．２以下、最も好ましくは１．１以下とするのが良い。
これは、上記体積抵抗率の環境依存性の指標値が１．７より大きいと導電性部材等に成形した場合に、環境の変化による抵抗値の変化が大きく、より大きな電源を必要とし、かかる導電性部材を用いた画像形成装置の消費電力や製品コストが上昇したりするためである。
【００４５】
本発明は上記した導電性ポリマー組成物を用いて成形されてなり、導電性ローラや導電性ベルトとしている導電性部材を提供している。
【００４６】
【発明の実施の形態】
以下、本発明の実施形態を説明する。
図１は導電層を形成する本発明の第１実施形態のイオン導電性ポリマー組成物の構造を示す模式図であって、イオン導電性ポリマーは、連続相１と、第１非連続相２、第２非連続相３とからなり、３つの相は海−島構造を呈している。第１非連続相２および第２非連続相３は連続相１中にほぼ均一に存在し、かつ、第１非連続層２は第２非連続相３を取り囲むように存在している。
なお、第２非連続相３は後述する第２実施形態では存在させていない。
【００４７】
図２は、上記導電性ポリマー組成物を原子間力顕微鏡（ＡＦＭ）式の走査型プローブ顕微鏡（ＳＰＭ）において位相モードで観察したモルフォロジー（１辺１０μｍ）を示す。図２において、連続相１は最も薄い色を呈し、第１非連続相２は最も濃い色を呈し、第２非連続相３は中程度の色濃度を呈している。図中で色の濃い部分は弾性率が高く、色の薄い部分は弾性率が低くなっている。
また、図２で示すように、体積分率は、連続相１＞第２非連続相３＞第１非連続相２となっている。
【００４８】
前記図１および図２に示すような海−島構造を呈するように、各相のポリマーの種類、量を規定すると共に、添加する塩の量および添加法を規定している。
上記イオン導電性ポリマー組成物には、全ポリマー１００重量部に対して０．０１〜２０重量部の陽イオンと陰イオンとに解離可能な塩を添加しており、上記第１非連続相２に上記塩を優先的に分配して偏在させ、第２非連続相３および連続相１には殆ど塩を添加していない。
【００４９】
上記第１非連続相２のポリマーは、連続相１を構成するポリマーよりも、解離可能な塩との親和性が高く、かつ、連続相１を構成するポリマーは、解離可能な塩を添加しない第２非連続相３を構成するポリマーよりも解離可能な塩との親和性が高いものとしている。即ち、上記各相のポリマーの塩との親和性は第１非連続相２＞連続相１＞第２非連続相３としている。
【００５０】
具体的には、後述の実施例２に示すように、本第１実施形態では、例えば、第１非連続相２を構成するポリマーとしてＥＯ−ＰＯ−ＡＧＥ共重合体（ＥＯ：ＰＯ：ＡＧＥ＝９０：４：６）を１０重量部用い、連続相１を構成するポリマーとして低ニトリルＮＢＲを６３重量部用い、解離可能な塩を殆ど添加しない第２非連続相３を構成するポリマーとして低極性の耐オゾン性ゴムであるＥＰＤＭを２７重量部用いている。即ち、解離可能な塩との親和性は、ＥＯ−ＰＯ−ＡＧＥ共重合体＞低ニトリルＮＢＲ＞ＥＰＤＭである。
【００５１】
第１非連続相２のＥＯ−ＰＯ−ＡＧＥ共重合体の体積抵抗率をＲ１、連続相１の低ニトリルＮＢＲの体積抵抗率をＲ２、第２非連続相３のＥＰＤＭの体積抵抗率をＲ３とすると、ｌｏｇ₁₀Ｒ１は７．９、ｌｏｇ₁₀Ｒ２は１０．２、ｌｏｇ₁₀Ｒ３は１４．８であり、（ｌｏｇＲ２−ｌｏｇＲ１）の値を２．３としている。上記第１、第２非連続相２、３を構成するポリマーと連続相１を構成するポリマーとの重量比は３７：６３としている。
【００５２】
上記導電性ポリマーに添加する陽イオンと陰イオンに解離可能な塩として、フルオロ基及びスルホニル基を有する陰イオンを備えた塩であるリチウム−ビス（トリフルオロメタンスルホニル）イミドを１．１重量部用いている。この塩は、ＰＣ／ＤＭＥ系混合溶媒（体積分率１／２）中，２５℃で０．１ｍｏｌ／ｌの塩濃度で測定した導電率が４．０ｍＳ／ｃｍである。また、数平均分子量（Ｍｎ）１万以下の低分子量ポリエーテル化合物や低分子量極性化合物である導電性可塑剤からなる媒体を介さずに配合している。
尚、リチウムービス（トリフルオロメタンスルホニル）イミドは、特公平１−３８７８１号公報（アンバール社等の出願）、或いは、特開平９−１７３８５６号公報（（財）野口研究所と旭化成工業（株）の出願）、或いは、特許３１１７３６９号公報・特開平１１−２０９３３８号公報（セントラル硝子（株）出願）、或いは、特開２０００−８６６１７号公報・特開２００１−１３９５４０号公報（関東電化工業（株）出願）、或いは、特開２００１−２８８１９３号公報（森田化学工業（株）出願）等、従来公知の方法により合成されたものを用いた。
また、リチウムートリス（トリフルオロメタンスルホニル）メタンは、米国特許第５５５４６６４号公報、或いは、特開２０００−２１９６９２号公報（（財）野口研究所と旭化成工業（株）の出願）、或いは、特開２０００−２２６３９２号公報（関東電化工業（株）出願）等、従来公知の方法により合成されたものを用いた。
【００５３】
上記導電性ポリマー組成物は、充填剤としてカーボンブラック９重量部、酸化亜鉛５重量部、ステアリン酸を１重量部、加硫剤として粉末硫黄１．５重量部、２種の加硫促進剤を各々１．５重量部、０．５重量部配合した加硫ゴム組成物からなる。
【００５４】
図３は上記導電性ポリマー組成物から形成した導電層１１を有する導電性ローラ１０を示す。該導電性ローラ１０は、導電性を有する円柱状の金属製の芯金１２と、芯金１２の表面側に上記導電層１１を備え、円筒状の導電層１１の中空部に芯金１２を圧入して取り付けている。
【００５５】
上記導電性ローラ１０は以下の方法により製造している。
まず、解離可能な塩とＥＯ−ＰＯ−ＡＧＥ共重合体とを混練機を用いて６０℃、３分混練し、ここで得られた混練物に、低ニトリルＮＢＲ、ＥＰＤＭ、その他各種配合剤を配合し、再度、６０℃、４分オープンロール、密閉式混練機等で混練し導電性ポリマー組成物を作製する。
【００５６】
この導電性ポリマー組成物をφ６０ｍｍの単軸押出機に投入し６０℃で中空チューブ状に押し出して予備成形し、この生ゴムチューブを所定寸法に裁断して予備成形体を得ている。この予備成形体を加圧水蒸気式加硫缶に投入し、発泡させる場合は化学発泡剤がガス化して発泡すると共に、ゴム成分が架橋する温度（１６０℃で１５〜７０分）で加硫して加硫ゴムチューブを得ている。
加硫条件はキュラストメーター等により測定し、９５％トルク上昇時間ｔ９５［分］程度を目安に適宜調整している。
なお、感光体汚染と圧縮永久歪みを低減させるため、なるべく充分な加硫量を得られるように条件を設定した方が望ましい。
【００５７】
芯金１２を用意し、その外周面にホットメルト接着剤を塗布した後、先に得られた加硫ゴムチューブに芯金を挿入し、加熱し接着した後、表面を研磨して導電層１１を目標寸法に仕上げた。導電性ローラ１０の導電層１１の寸法は、内径６ｍｍ、外径１４ｍｍ、長さ２１８ｍｍとしている。
【００５８】
上記導電層１１は、ＪＩＳＫ６２６２に記載の加硫ゴム及び熱可塑性ゴムの永久歪み試験法において、測定温度７０℃、測定時間２４時間で測定した圧縮永久歪みの値が１７％であり、印加電圧１００Ｖのもとで測定したＪＩＳ Ｋ６９１１に記載の体積固有抵抗率が１０^9.0［Ω・ｃｍ］である。
【００５９】
また、導電性ローラ１０の導電層を構成する例えば実施例２記載の導電性ポリマー組成物は、印加電圧１００Ｖでの体積抵抗率を１０^9.0Ω・ｃｍとし、２３℃、相対湿度５５％の環境下で、厚みが０．２５ｍｍのサンプルに対し１０００Ｖの定電圧を５時間連続印加した場合の体積抵抗率ρ_Ｖ［Ω・ｃｍ］を測定し、体積抵抗率の上昇量Δｌｏｇ₁₀ρ_Ｖ＝ｌｏｇ₁₀ρ_Ｖ（ｔ＝５ｈｒ．）−ｌｏｇ₁₀ρ_Ｖ（ｔ＝０ｈｒ．）の値を０．０８とし、１０℃相対湿度１５％、３２．５℃相対湿度９０％の条件下での体積抵抗率ρ_Ｖ［Ω・ｃｍ］を測定し、体積抵抗率の環境依存性Δｌｏｇ₁₀ρ_Ｖ＝ｌｏｇ₁₀ρ_Ｖ（１０℃相対湿度１５％）−ｌｏｇ₁₀ρ_Ｖ（３２．５℃相対湿度９０％）の値を０．８としている。
【００６０】
上記方法で製造された導電性ローラ１０の導電層１１は、上記連続相１、第１非連続相２、第２非連続相３を備え、第１非連続相２で第２非連続相３を取り囲むように存在させている。このように、モルフォルジーを制御すると共に、少量で抵抗値を下げ得る高性能の塩をＥＯ−ＰＯ−ＡＧＥ共重合体を主成分とする第１非連続相２に偏在させているため、電界を加えた時に起こる塩の製品外への移行や連続通電時の抵抗上昇等を防ぎながら、実用に必要な低電気抵抗値を得ることが出来る。
【００６１】
よって、低電気抵抗を維持しながら、電気抵抗の環境による変化や連続使用による変化を小さくすると共に、ローラの部位による電気抵抗のばらつきを低減し、安定して良好な画像を形成でき、環境に優しい導電性ローラを得ることができる。よって、現像ローラ、帯電ローラ、転写ローラ等に好適である。特に、高画質を要求されるカラー複写機あるいはカラープリンタ用のこれらの導電性ローラとして適している。
なお、発泡剤を配合し、発泡倍率が１００％以上５００％以下、好ましくは１５０％以上３００％以下であり、ＪＩＳ Ｋ６２５３に記載のタイプＥデュロメータで測定した硬度が６０度以下、好ましくは４０度以下の発泡層を有する発泡ローラとすることもできる。
【００６２】
かつ、上記導電層１１では、塩を殆ど分配していない第２非連続相３を設け、該第２非連続相３を塩を偏在させた第１非連続相２で取り囲むように存在させているため、導電性をあまり大きく損なうことなく、塩を偏在させた第１非連続相１の体積分率を抑えることができる。これにより、塩やそれを積極的に分配する第１非連続相１のポリマーの添加量を少なくしても、全体として低い体積抵抗率、ローラの製品抵抗値を得ることができる。かつ、上記陽イオンと陰イオンに解離可能な塩として用いるフルオロ基及びスルホニル基を有する陰イオンを備えた塩は高価であることより、この塩の添加量を少なくすることで、コスト上昇を抑えることができる。
【００６３】
図４及び図５は参考実施形態を示し、参考実施形態の導電性ポリマー組成物を用いて形成される導電性ベルト１３を転写ベルトとして用いた形態を示す。なお、上記第１実施形態の導電性ポリマー組成物を用いて図４に示す導電性ベルト１３としてもよいことはいうまでもない。
上記導電性ベルト１３は、２個のプーリー１４によって張架状態とされ、回転移動する導電性ベルト１３の上側の直線状部分１５に紙等のシート材１６を担持して搬送し、また感光体上に作られたトナー像をシート材１６に転写するものである。
【００６４】
上記導電性ベルト１３は、このような形態のみに限定されないがシームレスなベルト状の１層の導電性ポリマー組成物から形成した導電層２１のみからなる。該導電層２１は、図５に示すように、１相の連続相１’と、１相の第１非連続相２’とからなり、連続相１’と第１非連続相２’とは海−島構造を呈している。第１非連続相２’にのみ陽イオンと陰イオンに解離可能な塩を偏在させ、該第１非連続相２’を構成するポリマーは、連続相１’を構成するポリマーよりも、解離可能な塩との親和性が高いものとしている。
【００６５】
具体的には、解離可能な塩を偏在させた第１非連続相２’を構成するポリマーとしてポリエチレンオキサイドブロックナイロン１２共重合体からなる樹脂型帯電防止剤３０重量部用い、連続相１’を構成するポリマーとしてポリエーテルからなるソフトセグメントとポリエステルからなるハードセグメントから構成されるポリエステル系熱可塑性エラストマー１００重量部用いている。
【００６６】
第１非連続相を構成する樹脂型帯電防止剤の体積抵抗率をＲ１、連続相を構成するポリエステル系熱可塑性エラストマーの体積抵抗率をＲ２とするとｌｏｇ₁₀Ｒ１は９．０、ｌｏｇ₁₀Ｒ２は１３．４であり、（ｌｏｇ₁₀Ｒ２−ｌｏｇ₁₀Ｒ１）の値を４．４としている。第１非連続相２’を構成するポリマーと連続相１’を構成するポリマーとの重量比は２３：７７としている。
【００６７】
陽イオンと陰イオンに解離可能な塩としては、フルオロ基及びスルホニル基を有する陰イオンを備えた塩であるリチウム−ビス（トリフルオロメタンスルホニル）イミドを１．５重量部用いている。この塩は、ＰＣ／ＤＭＥ系混合溶媒（体積分率１／２）中、２５℃で０．１ｍｏｌ／リットルの塩濃度で測定した導電率が４．０ｍＳ／ｃｍであり、分子量１万以下の低分子量ポリエーテル化合物や低分子量極性化合物である導電性可塑剤からなる媒体を介さずに配合している。
【００６８】
導電性ベルト１３は以下の方法により製造している。
解離可能な塩と樹脂型帯電防止剤とをタンブラーを用いてドライブレンドする。このドライブレンド物を速やかに２軸押出機に送り込む。１７０〜２１０℃で、２分混練した後、冷却してペレット化する。ここで得られた混練物のペレットに、ポリエステル系熱可塑性エラストマーのペレットを上記と同様にドライブレンドし、再度、２軸押出機を用いて２１０〜２７０℃で２分混練し、冷却して導電性ポリマー組成物のペレットを作製する。この導電性ポリマー組成物のペレットを樹脂用の押出成形機によりベルト状に成形している。
【００６９】
導電性ベルト１３は、印加電圧１００Ｖのもとで測定したＪＩＳ Ｋ６９１１に記載の体積固有抵抗率が１０^9.6［Ω・ｃｍ］である。
【００７０】
また、導電性ベルト１３は、２３℃、相対湿度５５％の環境下で、厚みが０．２５ｍｍのサンプルに対し、１０００Ｖの定電圧を５時間連続印加した場合の体積抵抗率ρ_Ｖ［Ω・ｃｍ］を測定し、体積抵抗率の上昇量Δｌｏｇ₁₀ρ_Ｖ＝ｌｏｇ₁₀ρ_Ｖ（ｔ＝５ｈｒ．）−ｌｏｇ₁₀ρ_Ｖ（ｔ＝０ｈｒ．）の値を０．３６とし、１０℃相対湿度１５％、３２．５℃相対湿度９０％の条件下での体積抵抗率ρ_Ｖ［Ω・ｃｍ］を測定し、体積抵抗率の環境依存性Δｌｏｇ₁₀ρ_Ｖ＝ｌｏｇ₁₀ρ_Ｖ（１０℃相対湿度１５％）−ｌｏｇ₁₀ρ_Ｖ（３２．５℃相対湿度９０％）の値を１．４としている。
【００７１】
上記導電性ベルト１３は、陽イオンと陰イオンに解離可能な塩を第１非連続相２’に偏在させた導電層２１を備え、かつ、この添加する塩として少量で抵抗値を低下できる塩を用い、さらには各相に用いるポリマーを適切に選択しているため、電界を加えたときに起こる塩の系外への移行や連続通電時の抵抗上昇等を防ぎながら、かつ、実用に必要な低電気抵抗値を得ることができる。また、厚み方向には適度な柔軟性を有する一方、長さ方向には伸びにくい。
【００７２】
上記実施形態では、本発明の導電性ベルトを特に転写ベルトとして用いた場合について詳しく記載したが、その他、例えば、画像形成装置に用いられる中間転写ベルト、定着ベルト、現像ベルト、搬送ベルト等としても用いることができる。特に、白色のベルトとすると、トナーの付着が簡単に目視可能となるため、クリーニング性能の評価に適し、中間転写ベルトとして好適に用いることができる。
【００７３】
上記実施形態以外にも、連続相を構成するポリマー、非連続相を構成するポリマー、解離可能な塩は、本発明の範囲内である限り、前記したように種々の材料を用いることができる。必要に応じて各種配合材料を変更し要求性能に合わせて電気特性を最適化することができる。各種配合材料の配合種や配合量も本発明に規定した範囲内で適宜設定することができる。上記以外の方法により混練等を行うこともでき、従来公知の方法等により導電性ポリマー組成物を作製し、導電性部材を成形することができる。
【００７４】
以下、本発明の導電性ポリマー組成物を用いて形成される導電性部材の実施例、参考実施例、比較例について詳述する。
まず、導電性ローラの実施例、参考実施例及び比較例について示す。
実施例１〜４、参考実施例１、２、比較例１〜５については、表１、表２に記載の各配合材料を上記実施形態と同様の方法により混練、押出、加硫、成形加工、研磨して導電性ローラを作製した。ヒューレットパッカード社製Laser Ｊｅｔ４０５０型レーザービームプリンタ搭載の転写ローラ用の導電性ローラとした。
【００７５】
これと並行して、混練機からリボン取りしたゴムをローラヘッド押出機により押し出してシート状に成形し、それを１６０℃で最適時間加硫缶にて加硫したあと、厚さが約2mmとなるようにスライスし、体積抵抗率（体積固有抵抗値）評価用の加硫ゴムスラブシートを得た。これらのローラやゴムスラブシートを用いて行った評価結果及び後述するローラとしての各種評価を表１、表２に示す。
尚、連続通電時の抵抗上昇の測定に際しては、導電性ベルトの例と条件を合わせるために、さらに厚さが０．２５ｍｍ前後になるようにスライスしたものを作成して用いた。
【００７６】
【表１】

【００７７】
【表２】

【００７８】
（実施例１〜４、参考実施例１、２）
第１非連続相を構成するポリマーとしてＥＯ−ＰＯ−ＡＧＥ共重合体あるいはエピクロルヒドリンゴムを用い、これに陽イオンと陰イオンに解離可能な塩であるリチウム−ビス（トリフルオロメタンスルホニル）イミドあるいはリチウム−トリス（トリフルオロメタンスルホニル）メタンを偏在させた。連続相として低ニトリルＮＢＲを用い、第２非連続相としてＥＰＤＭを用いた。実施例２以外は発泡ローラとした。
【００７９】
（参考実施例３）
エピクロルヒドリンゴム５０ｐｈｒ分とＮＢＲ、炭酸カルシウム、ハイドロタルサイト、亜鉛華、ステアリン酸を混入し、１２０℃に予熱した密閉式混練機で混練した。混練しながら予め作製したエピクロルヒドリンゴム（１０ｐｈｒ分）のチオウレア架橋剤（加硫剤２）マスターバッチおよびチオウレア架橋剤用の架橋促進剤（加硫促進剤３）を入れ動的架橋した。練りトルクのチャートを見ながら架橋が進み、トルクピーク付近で混練を一旦完了した。続いて５０℃まで冷却し、混練機により、硫黄、加硫促進剤１、加硫促進剤２を混入し、動的架橋組成物を得た。これを、実施例１〜４、参考実施例１、２と同様にチューブ状に押し出して予備成形し、そのチューブを裁断したものを１６０℃で１０〜７０分加硫して導電層を得た。
【００８０】
（比較例１〜５）
比較例１は陽イオンと陰イオンに解離可能な塩を用いなかった。比較例２、３は低ニトリルＮＢＲからなる連続相とＥＰＤＭからなる非連続相の２相構造とし、連続相に陽イオンと陰イオンに解離可能な塩を偏在させた。比較例４、５は１種のポリマーから構成される１相のみの構造とし、その１相に陽イオンと陰イオンに解離可能な塩を配合した。比較例１、２は発泡ローラとした。
【００８１】
ＥＯ−ＰＯ−ＡＧＥ共重合体あるいはエピクロルヒドリンゴムは、解離可能な塩と予め混練したものを用いた。カーボンブラックとＥＰＤＭの併用系では、カーボンブラックをＥＰＤＭに予め練りこんでマスターバッチ化したものを用いた。参考実施例２ではカーボンブラックをＮＢＲに予め練りこんでマスターバッチ化したものを用いた。加硫促進剤１はジベンゾチアジルジスルフィド、加硫促進剤２はテトラメチルチウラムモノスルフィドとし、発泡剤１は４，４’−オキシビス（ベンゼンスルホニルヒドラジド）とした。
【００８２】
陽イオンと陰イオンに解離可能な塩を偏在させた非連続相を構成するポリマーの体積抵抗率Ｒ１、連続相を構成するポリマーの体積抵抗率Ｒ２、陽イオンと陰イオンに解離可能な塩を偏在させない非連続相を構成するポリマーの体積抵抗率Ｒ３の測定は塩を入れずに行った。
例えば、実施例１あるいは実施例２では、ＺＳＮ８０３０を１００重量部、シースト３を９重量部、銀嶺Ｒを５重量部、ステアリン酸４９３１を１重量部、粉末硫黄を１．５重量部、ノクセラーＤＭを１．５重量部、ノクセラーＴＳを０．５重量部配合した組成物の体積抵抗率を測定した。測定時に印加電圧は１００Ｖ、測定環境は２３℃、相対湿度５５％とした。
【００８３】
また、ウレタン組成物を用いた導電性ローラの参考実施例、比較例について詳述する。参考実施例４および比較例６〜８について、各々下記の表３、表４に記載の配合からなる材料を用い導電層を作製した。
【００８４】
【表３】

【００８５】
【表４】

【００８６】
（参考実施例４）
２種のポリエーテルポリオール１、２を用い、陽イオンと陰イオンに解離可能な塩であるリチウム−ビス（トリフルオロメタンスルホニル）イミドを用いた。
なお、ポリエーテルポリオール１とポリエーテルポリオール２はどちらもＰＰＧ系ポリオールで水酸基価も同一であり、基本構造はほぼ同一のものである。よって、これらは均一に相溶し、１つの相を形成する。
連続相は塩との親和性がかなり低い液状ポリブタジエンポリマー（端末イソアソアネートプレポリマー１）からなり、ｌｏｇ₁₀Ｒ２は１４．１である。
非連続相は上記のように塩との親和性が比較的高いＰＰＧ系ポリオールからなる構成とした。ｌｏｇ₁₀Ｒ１は１１．１であり、ｌｏｇ₁₀Ｒ２−ｌｏｇ₁₀Ｒ１は３．０となる。
以上により、イソシアネートプレポリマーとポリオール等が反応して出来たポリウレタン組成物中では、非連続相と連続相の比率は４０：６０程度となる。
具体的には、以下のようにして導電層を作製した。
ポリエーテルポリオール１とポリエーテルポリオール２、及び、芳香族ジアミン、消泡剤、レベリング剤等を計量した後、室温下で回転式の撹拌機等を用いて撹拌して、均一に混合する。その後、その混合液を減圧下で脱泡した。同じく、減圧下で脱泡した末端イソシアネートプレポリマーを、先に調整した混合液と混ぜて、再び撹拌・脱泡した後、物性評価用のスラブや導電性ローラ作製用各種金型に流し込む。金型に流し込んだ後、１５０℃で６０分加熱することにより、硬化反応を起こして、所望のスラブや導電性ローラが得られる。
尚、導電性ローラに用いる場合は、金属製シャフトにウレタン用プライマーを塗ったものをセットした金型に、ポリオールを含む上記混合液と、イソシアネートプレポリマーとを均一に混合したものを、流し込むと良い。
ウレタン用プライマーとしては、例えば住化バイエルウレタン（株）製、スミジュール４４Ｖ２０と同じく住化バイエルウレタン（株）製ＳＢＵポリオール０７５９とを重量比で１：２に混合したもの等が好適に用いられる。
ウレタン組成物の体積抵抗率およびその環境依存性は１３０×１３０×２ｍｍのスラブを用いて測定しているが、連続通電時の抵抗上昇は１３０×１３０×０．２５ｍｍのものを用いた。
【００８７】
（比較例６〜８）
比較例６，７は解離可能な塩を配合しなかった。比較例８は、ＰＰＧポリオール（ポリエーテルポリオール１、２）とＰＰＧプレポリマー（末端イソシアネートプレポリマー２）を用いたが、塩との親和性がＰＰＧよりも低い液状ポリブタジエンプレポリマー等は用いずに、基本的には、解離可能な塩との親和性が、比較的高い相のみからなる構成とした。いずれも参考実施例４と同様の方法により導電層を作製した。
【００８８】
（体積抵抗率の測定）
上記の様に作製した測定用シートに対して、アドバンテストコーポレーション社製の超高抵抗微小電流計Ｒ−８３４０Ａを用いて、２３℃相対湿度５５％の恒温恒湿条件下で測定した。測定方法は、ＪＩＳ Ｋ６９１１に記載の体積抵抗率（体積固有抵抗）の測定方法に従い、また測定時の印加電圧は１００Ｖとした。表中にその常用対数値を表示する。また、導電性ベルトの実施例・比較例については、得られた導電性ベルトをそのまま用いて、ベルトの周方向４点×長手方向５点の計２０点で上記と同様に測定し、log₁₀ρ_Ｖ[Ω.cm]の平均値を表中に記載した。
【００８９】
（ローラ抵抗値）
温度２３℃、相対湿度５５％雰囲気下で、図６に示すように、芯金４２を通した導電層４１をφ３０のアルミドラム４３上に当接搭載し、電源４４の＋側に接続した内部抵抗ｒ（１００Ω〜１０ｋΩ）の導線の先端をアルミドラム４３の一端面に接続すると共に電源４４の−側に接続した導線の先端を導電層４１の他端面に接続して通電を行った。芯金４２の両端部に５００ｇずつの荷重Ｆをかけ、芯金４２とアルミドラム４３間に１０００Ｖの電圧をかけながらアルミドラム４３を回転させることで間接的に導電性ローラ４０を回転させた。このとき周方向に３６回抵抗測定を行い、その平均値を求めた。内部抵抗の値は、ローラの抵抗値のレベルにあわせて、測定値の有効数字が極力大きくなるように調節した。この図６の装置で、印加電圧をＥとすると、ローラ抵抗値ＲはＲ＝ｒ×Ｅ／Ｖ−ｒとなるが、今回−ｒの項は微小とみなし、Ｒ＝ｒ×Ｅ／Ｖとし、内部抵抗ｒにかかる検出電圧Ｖより、ローラ抵抗値Ｒを算出した。表中には、そのローラ抵抗値の平均値の常用対数値を用いて示している。
【００９０】
（体積固有抵抗値環境依存性）
導電性ベルトの実施例・比較例について、１０℃相対湿度１５%（LL環境）と、３２．５℃相対湿度９０％(HH環境)の環境下においても、上記と同様にして、１００Ｖ印加時の導電性ベルトの体積抵抗率を測定した。
そして、体積抵抗率の環境依存性：Δlog₁₀ρ_Ｖ(LL-HH)[Ω.cm]= log₁₀ρ_Ｖ(１０℃,１５％rh.)-log₁₀ρＶ(３２．５℃,９０％rh.) の式に従い、環境依存性の数値を計算し、その値を表５、表６に記載する。この値が1.7を越えると好ましくない。
【００９１】
（ローラ抵抗値の周ムラ）
図６に示す装置を用い、温度２３℃、相対湿度５５％雰囲気下で、芯金の両端に５００ｇずつの荷重Ｆをかけ、アルミドラムを回転数３０ｒｐｍで回転させることで導電性ローラを回転させた状態で、１０００Ｖの印加電圧をかけたとき、１周内の周むら（（周方向の電気抵抗の最大値／周方向の電気抵抗の最小値）の比率）を求めた。周むらは１．０〜１．３、より好ましくは、１．０〜１．２、さらに好ましくは、１．０〜１．１５であるのが良い。
【００９２】
（連続通電時の抵抗上昇）
ローラ抵抗値の測定による。
[実施例１〜４、参考実施例１〜３]、[比較例１〜５]
２３℃、相対湿度５５％の環境下で、ローラ抵抗値[Ω]の測定時と同様の状態で、ローラに１０００Ｖの定電圧を96時間連続印加した。このときの、電圧印加直後のローラ抵抗値R(t=０)と、９６時間印加後のローラ抵抗値R(t=９６hr.)の値を上記と同様にして測定し、これらの値を用いて連続通電時の抵抗上昇量：Δlog₁₀ R(t=96-0hr.)[Ω]= log₁₀ R(t=96hr.)-log₁₀ R(t=0)を計算した。数値は表１〜４中に示す。尚、アルミドラムの回転数が３０ｒｐｍ、径が３０ｍｍφのため、回転時の線速度は、９４ｍｍ／分となる。
【００９３】
（連続通電時の抵抗上昇）
体積抵抗率の測定による。
２３℃、相対湿度５５％の環境下で、体積固有抵抗値の測定時と同様の状態で、導電性ベルト内あるいは厚み０．２５ｍｍのスラブのある１点において、アドバンテストコーポレーション社製のデジタル超高抵抗微小電流計R-8340Aを用いて、１０００Ｖの定電圧を５時間連続印加した。このときの、電圧印加直後のベルトあるいはスラブの体積固有抵抗値ρ_Ｖ(t=０)と、５時間印加後のベルトあるいはスラブの体積固有抵抗値ρ_Ｖ(t=５hr.)の値を、上記と同様にして測定し、これらの値を用いて連続通電時の抵抗上昇量：Δlog₁₀ρ_Ｖ(t=５-０hr.)[Ω.cm] = log₁₀ρ_Ｖ(t=５hr.)-log₁₀ρ_Ｖ(t=０)を計算した。数値は各表中に示す。
【００９４】
（面内むら）
導電性ベルトの面内むらの測定は、上記導電性ベルトの体積固有抵抗値の測定において、１本のベルト内で得られた２０点の体積固有抵抗値について、その最大値を最小値で除した値を計算し、それを表５、表６中に記載した。これにより、実施例・比較例中のいずれのベルトも、むらがほとんどなく非常に均一であることがわかる。他方、カーボン導電のベルトでは、この値が２から１０程度、大きいものでは、１００程度になることもあり得る。
導電性ローラ用ゴム組成物およびウレタン組成物の体積抵抗率の面内むらについては、作製した１３０×１３０×２ｍｍのスラブ中の縦５点×横４点の計２０点において、三菱化学株式会社製ハイレスタＵＰとＵＲＳタイプのプローブを用いて測定し、その最大値を最小値で除した値を計算し、それを各表中に記載した。
【００９５】
（圧縮永久ひずみ）
上記で得られた導電性ローラを１０ｍｍ幅で端面に平行にカットした試験片を用いて、ＪＩＳ Ｋ６２６２に記載の加硫ゴム及び熱可塑性ゴムの永久ひずみ試験方法に従い、測定温度７０℃、測定時間２２〜２４時間、圧縮率２５％で測定した。この圧縮永久ひずみの値が３０％を越える場合は、ローラになったときの寸法変化が大きくなりすぎて実用に適さなくなる可能性が高い。
【００９６】
（感光体汚染試験）
実施例１〜実施例４、参考実施例１〜４、比較例１〜比較例８においては、以下の方法で試験した。
ヒューレットパッカード社製のＬａｓｅｒ Ｊｅｔ４０５０型レーザービームプリンタのカートリッジ（カートリッジタイプ Ｃ４１２７Ｘ）にセットされている感光体に、実施例・参考実施例・比較例の加硫ゴムスラブシートを押しつけた状態で、３２．５℃，相対湿度９０％の条件下で２週間保管する。その後、感光体から加硫ゴムスラブシートを除去し、当該感光体を用いて上記プリンターにてハーフトーンの印刷を行い、印刷物に汚れが出るかどうかを次の基準で調査した。
○：印刷物を目で見る限り汚染なし
△：軽度の汚染（５枚以内の刷り込みにより、目で見て判らない程度にまでとれる使用上問題ない汚染）
×：重度の汚染（５枚以上刷り込んでも、印刷物を目で見て異常が判る汚染）
尚、実施例５，６、比較例９，１０の導電性ベルトについては、得られた導電性ベルトの切片と、富士ゼロックス株式会社製のレーザービームプリンタＤｏｃｕＰｒｉｎｔ １８０及び、それのカートリッジ（商品コード ＣＴ３５００３５）にセットされている感光体を用い、上記と同様にして評価した。但し、保管条件は、４５℃，相対湿度８０％とした。
【００９７】
（硬度の測定）
導電性ローラについて、ＪＩＳ Ｋ６２５３に記載のタイプＥデュロメータを用いて５００ｇの荷重をかけたもとでの硬度を測定した（デュロメータＥ硬度）。但し、ソリッドローラについては、荷重を１０００ｇとした。
【００９８】
表１、表２に示すように、実施例１〜４、参考実施例１〜３の導電性ポリマー組成物から得られた導電性ローラは、所要の１相の第１非連続相に解離可能な塩を偏在させているため、いずれも電気特性に優れると共に移行汚染等の問題も生じなかった。特に、電気抵抗の環境依存性が小さい上に、連続通電時の抵抗上昇も少なかった。また、発泡により低硬度化された導電性ポリマー組成物、あるいはそれを用いた発泡ローラとしても通電時の抵抗上昇が小さく、良好であった。
【００９９】
一方、比較例１は解離可能な塩を配合しなかったため体積固有抵抗値、及びローラ抵抗値が高すぎた。比較例２、３は連続相に解離可能な塩が偏在されたため連続通電時の抵抗上昇が大きく不適であった。比較例４、５は１相の系で解離可能な塩を用いたため連続通電時の抵抗上昇が大きく不適であった。
【０１００】
また、上述した図２は、実施例２を原子間力顕微鏡（ＡＦＭ）式の走査型プローブ顕微鏡（ＳＰＭ）において位相モードで観察したモルフォロジーであった。また、比較例３のモルフォロジー（１辺１０μｍ）を図７に示す。比較例３は１つの連続相と１つの非連続相からなり、解離可能な塩は連続相に偏在させたものである。
【０１０１】
さらに、図８は、実施例１と比較例２の導電性ポリマー組成物からなる導電性ローラの連続通電時の抵抗変化を示している。横軸を通電時間、縦軸をローラ抵抗値とした。実施例１と比較例２では初期状態でのローラ抵抗値はほぼ同等であるが、図８に示すように、連続通電により比較例２は抵抗が著しく上昇するのに対して、実施例１はごくわずかに上昇するのみであった。
【０１０２】
表３、表４に示すように、参考実施例４の導電性ウレタンゴム組成物及び、それを用いた導電性ローラは、所要の１相の第１非連続相にのみ解離可能な塩を偏在させているため、いずれも電気特性に優れると共に移行汚染等の問題も生じなかった。特に、電気抵抗の環境依存性が小さい上に、連続通電時の抵抗上昇も少なかった。
【０１０３】
一方、比較例６、７は解離可能な塩を含まないため、抵抗値が高く不適であった。比較例８は、基本的にはほぼ１相の系で解離可能な塩を用いたため、連続通電時の抵抗上昇が大きく不適であった。
【０１０４】
次に、導電性ベルト用の導電性ポリマー組成物の実施例、比較例について示す。
表５、表６に記載の各配合材料を上述した方法によりタンブラー、２軸押出機を用いて配合、混練した後に、樹脂用の押出成形機により押出して、内径１６８ｍｍ、平均厚み０．２５ｍｍ、幅３５０ｍｍの転写ベルト用の導電性ベルトを作製した。評価結果及び上記したベルトとしての各種評価を表５、表６に示す。
【０１０５】
【表５】

【０１０６】
【表６】

【０１０７】
（参考実施例５，６）
非連続相を構成するポリマーとして本発明で用いる陽イオンと陰イオンに解離可能な塩との親和性が非常に高い、ポリエチレンオキサイドブロックナイロン１２共重合体やポリエーテルエステルアミド共重合体からなる樹脂型帯電防止剤を用い、これに陽イオンと陰イオンに解離可能な塩であるリチウム−ビス（トリフルオロメタンスルホニル）イミドを偏在させた。連続相として上記の樹脂型帯電防止剤よりは塩との親和性は小さいが、多少の親和性は有するポリユーテルのソフトセグメントとポリエステルのハードセグメントからなるポリエステル系熱可塑性エラストマーを用いた。リチウム−ビス（トリフルオロメタンスルホニル）イミドの濃度が５ｗｔ％となるような上記の樹脂型帯電防止剤とのマスターバッチを作製し、それを用いた。尚、比較例１０のデータ中のＲ２の値や組成物の体積固有抵抗値が、それなりに低い値を示していることから、これら実施例で用いた熱可塑性エラストマー（ペルプレン）は、本発明で用いる塩とはそれなりの親和性を有することがわかる。
【０１０８】
（比較例９、１０）
比較例９は、リチウム−ビス（トリフルオロメタンスルホニル）イミドをアジピン酸ジブトキシエトキシエチルに２０ｗｔ％溶解したものを、ポリエステル系熱可塑性エラストマー（ポリエーテル−ポリエステルブロック共重合体ペルプレンＰ９０ＢＤ）に配合して用いた。塩の量は０．５重量部とした。比較例１０はリチウム−ビス（トリフルオロメタンスルホニル）イミドを低分子量のポリエーテル化合物や導電性可塑剤からなる低分子量極性化合物からなる媒体を用いずにポリエステル系熱可塑性エラストマー１相中に直接分散させて用いた。
【０１０９】
樹脂型帯電防止剤１は、ポリエチレンオキサイドブロックナイロン１２共重合体を主成分とする。樹脂型帯電防止剤２は、ポリエーテルエステルアミド共重合体を主成分として含んでいる。
【０１１０】
表５、表６に示すように、参考実施例５、６は所要の１相の第１非連続相に解離可能な塩を偏在させているため、いずれも電気特性に優れると共に移行汚染等の問題も生じなかった。特に、電気抵抗の環境依存性が小さい上に、連続通電時の抵抗上昇も少なかった。
【０１１１】
一方、比較例９は、１相の系で解離可能な塩を用い、またかかる塩を低分子量極性化合物からなる媒体を用いて分散させたため連続時の抵抗上昇が非常に大きく、感光体汚染も生じ不適であった。比較例１０は、連続通電時の抵抗上昇が大きく、環境依存性もやや大きかった。
【０１１２】
【発明の効果】
以上の説明より明らかなように、本発明によれば、連続相と２相の非連続相とからなる相構造を有し、陽イオンと陰イオンに解離可能な塩を非連続相に偏在させ、かつ、陽イオンと陰イオンに解離可能な塩を偏在させた非連続相を構成するポリマーは、連続相を構成するポリマーよりも、陽イオンと陰イオンに解離可能な塩との親和性を高くしている。このため、非連続相中での塩の自由度を高め低い電気抵抗を維持しながら、電界を加えたときの塩の系外への流出を抑制できるため、塩の組成物外への移行や連続動電時の抵抗上昇等を防ぐことができる。更には、塩が非連続相中に偏在するため温度や湿度等の環境の影響も受けにくく、かつ、イオン導電によるため、電気抵抗のばらつきや電圧依存性も小さい。
【０１１３】
また、電界をかけ続けても塩が移行して表面に出たり、抵抗値が上昇することが抑制されているため、導電性に優れた塩の使用が可能となり、導電性に優れた塩の少量の配合でも優れた導電性を得ることができる。よって、ブリード、ブルームや感光体汚染・移行汚染等の問題点を生じることもない上に、圧縮永久ひずみや硬度等の他の物性に及ぼす影響も極力低減することができる。
【図面の簡単な説明】
【図１】 本発明の第１実施形態の導電性ポリマー組成物の構造を示す模式図である。
【図２】 第１実施形態の実施例２の導電性部材を形成する導電性ポリマーの相構造（モルフォロジー）を示す図である。
【図３】 第１実施形態の導電性ポリマーより形成した導電層を備えた導電性ローラの概略図である。
【図４】 本発明の参考実施形態の導電性ポリマー組成物を用いて形成される導電性ベルトの概略図である。
【図５】 参考実施形態の導電性ポリマー組成物の構造を示す模式図である。
【図６】 ローラ抵抗値等のローラの電気特性の測定装置の概略図である。
【図７】 比較例３の導電性部材を形成する導電性ポリマーの相構造（モルフォロジー）を示す図である。
【図８】 実施例１と比較例２のローラの連続通電時の抵抗変化を示すグラフである。
【符号の説明】
１、１’連続相
２，２’第１非連続相
３ 第２非連続相
１０ 導電性ローラ
１１、２１ 導電層
１２ 芯金
１３ 導電性ベルト[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a conductive polymer composition.And its manufacturing methodIn detail, in an ion conductive polymer composition containing an ion conductive additive salt, it prevents salt precipitation when an electric field is applied, resistance increase during continuous energization, and the like. This is to improve the property and change with time and to obtain stable electrical characteristics.
[0002]
[Prior art]
As a method of imparting conductivity to various conductive members, a method using an electronic conductive polymer composition in which a conductive filler such as a metal oxide powder or carbon black is blended in a polymer, urethane, acrylonitrile butadiene rubber ( NBR), and an ion conductive polymer composition such as epichlorohydrin rubber.
[0003]
In the case of using an electroconductive polymer composition obtained by blending a conductive filler such as metal oxide powder or carbon black, the electrical conductivity is increased by a slight change in addition amount particularly in the required semiconductive region. Since the resistance value changes abruptly, it becomes very difficult to control. For this reason, since it is difficult to uniformly disperse the conductive filler in the polymer composition, when the roller or belt-like conductive member is used, the resistance value is increased in the circumferential direction and longitudinal direction of the roller and in the plane of the belt. This causes the problem of variation.
[0004]
There is a problem that the variation in the electrical resistance value is not only within one product but also between products. Furthermore, the electrical resistance value of the conductive roller or conductive belt obtained from the conductive polymer composition depends on the applied voltage and does not show a certain resistance value. In particular, when carbon black is used as the conductive filler, these tendencies appear remarkably. Such a phenomenon may make mechanical control difficult and increase costs in an image forming process such as charging, development, transfer, and fixing. In addition, when carbon is used, there is a problem that it cannot be colored freely. From the above points, ion conductive members tend to be preferred, and various proposals have been made.
[0005]
For example, in Japanese Patent Application Laid-Open No. 10-169641, a semiconductive polymer elastic member in which a quaternary ammonium salt is added to a polymer material as a base material and a resistance value at the time of continuous energization is defined while considering the use environment Has been proposed.
[0006]
[Patent Document 1]
Japanese Patent Laid-Open No. 10-169641
[0007]
[Problems to be solved by the invention]
However, in the above-mentioned Japanese Patent Application Laid-Open No. 10-169641, by adding a quaternary ammonium salt having a specific anion, an attempt is made to reduce an increase in resistance value during continuous energization generated in an ion conductive member. However, there is a problem that the environmental dependency (temperature dependency + humidity dependency) of the electrical resistance value cannot be sufficiently reduced. Further, the salt to be mixed may move to the surface and contaminate contact substances such as a photoreceptor. As described above, in the conductive member, not only the increase in the resistance value during continuous energization is reduced, but also the environmental dependency of the electrical resistance and the problem of migration contamination to contact substances such as salt to be mixed with the photosensitive member. It is also necessary to consider.
[0008]
  As an ionic conductive conductive agent, there are conductive oligomers and conductive plasticizers containing a polyether structure such as polyethylene oxide (both Mn <10000), but these are not fixed in the polymer composition, There is a problem that causes bleed and bloom. In particular, in the case of conductive rollers and conductive belts for copying machines and printers, these transfer and contaminate the photosensitive member, contaminating the image, and in the worst case, altering and destroying the photosensitive memberMoaThe
[0009]
  Also perchlorineacidIn systems using metal salts such as lithium and ion-conductive additive salts such as various quaternary ammonium salts, the ions from which the salt is dissociated are continuously energized, although this depends on the blending amount and compatibility with the base polymer. Sometimes it moves toward the electrode, so the resistance value may increase considerably over time. In addition, added salt or the like may be deposited on the surface of the conductive member, and depending on the substance, the photoreceptor may be contaminated.
  In particular, when a medium composed of a low molecular weight polyether compound or a low molecular weight polar compound is used to disperse the added salt, the salt easily moves in the polymer and the conductivity is improved. Precipitates easily. Furthermore, these low molecular weight media used also migrate to the surface, and when used for a long time, there may be a problem that migration contamination and toner sticking occur, resulting in loss of practicality. When used continuously for a long time as an actual product, these points often cause problems.
[0010]
The present invention has been made in view of the above-described problems, reduces the environmental dependency (temperature dependency + humidity dependency) of electrical resistance while maintaining a sufficiently low resistance value, and resistance during continuous energization. It is an object of the present invention to provide an ion conductive polymer composition with a small increase.
[0011]
[Means for Solving the Problems]
  In order to solve the above problems, the present invention provides:First,Conductivity including ionic conductivity added saltpolymerA composition comprising:
  With continuous phaseThe first discontinuous phase and the second discontinuous phase2PhaseA non-continuous phase, and the continuous phaseTwo-phaseWith discontinuous phaseButSea-island structureTheNone,
  The polymer constituting the continuous phase is acrylonitrile butadiene rubber (NBR),the aboveFirstDiscontinuousThe polymer constituting the phase is a polyoxyalkylene copolymer or epihalohydrin polymer, the polymer constituting the second discontinuous phase is ethylene propylene diene copolymer rubber (EPDM), and the first discontinuous phase is constituted. The polymer that has the ability to reduce electrical resistanceSalts dissociable into cations and anionsAnd the affinity between the salt and the salt of the polymer of each phase is such that the first discontinuous phase> the continuous phase> the second discontinuous phase, the salt is mixed and unevenly distributed in the first discontinuous phase, The salt is hardly dispersed in the second discontinuous phase and the continuous phase,Suppressing the movement of salt out of phaseAnd
The electrical resistance value (volume resistivity) of each of the phases is defined as first discontinuous phase <continuous phase <second discontinuous phase, and the volume fraction of each phase is continuous phase> second discontinuous phase> first non-continuous. The weight ratio between the polymer constituting the continuous phase and the polymer constituting the two discontinuous phases and the polymer constituting the continuous phase is (the polymer constituting the two discontinuous phases: the polymer constituting the continuous phases) Polymer) = (20:80) to (45:55),
The above salt is blended in a proportion of 0.01 parts by weight or more and 20 parts by weight or less with respect to 100 parts by weight of the total polymer component, and is a vulcanized rubber composition.An electrically conductive polymer composition is provided.
  Further, secondly, a conductive polymer composition containing an ion conductive additive salt,
It consists of a continuous phase and one discontinuous phase, and the continuous phase and the discontinuous phase form a sea-island structure,
  The polymer constituting the continuous phase is a polyester-based thermoplastic elastomer, the polymer constituting the discontinuous phase is a polyoxyalkylene copolymer, and the polymer constituting the discontinuous phase has a cation reducing ability. And a salt capable of dissociating into an anion, and the polymer constituting the discontinuous phase has a higher affinity for the salt capable of dissociating into the cation and the anion than the polymer constituting the continuous phase. The salt is unevenly distributed in the continuous phase, the salt is hardly dispersed in the continuous phase, and the movement of the salt to the outside is suppressed,
The weight ratio of the polymer constituting the discontinuous phase and the polymer constituting the continuous phase is (the polymer constituting the discontinuous phase: the polymer constituting the continuous phase) = (20:80) to (45: 55)
The salt capable of dissociating into the cation and the anion is blended at a ratio of 0.01 parts by weight or more and 20 parts by weight or less with respect to 100 parts by weight of the total polymer component, and is a thermoplastic elastomer composition. A featured conductive polymer composition is provided.
[0012]
As a result of intensive studies by the inventors, the inventors focused on the arrangement of salts that can achieve low electrical resistance and the affinity between the salt and the polymer, and studied and experimented on polymer materials and ionic conductive additive salts to be blended. This is based on the finding of a phase structure capable of preventing the migration of the salt to the outside of the composition while maintaining good electrical characteristics due to ions.
[0013]
  as mentioned above,In the first and second inventions,With continuous phase1 phase or 2 phaseThe above cation and anion having a sea-island structure consisting of a discontinuous phase, having a salt dissociable into a cation and an anion unevenly distributed in the discontinuous phase, and having a high electrical conductivity and a large ability to lower electrical resistance. Since the polymer constituting the discontinuous phase in which the dissociable salt is unevenly distributed has higher affinity with the salt than the polymer constituting the continuous phase, the degree of freedom of the salt in the discontinuous phase is increased. In addition, while maintaining a low electrical resistance, it is possible to suppress the migration of salt out of the system when an electric field is applied. Thus, by being able to suppress the migration of salt,ThroughIt is possible to prevent resistance rise during power transmission and contamination outside the system. Furthermore, since the salt is present in the discontinuous phase, it is hardly affected by the environment such as temperature and humidity. Moreover, due to ionic conduction, variations in electrical resistance and voltage dependence are small.
[0014]
Conventionally, in order to reduce the resistance value of the entire composition as much as possible, attempts have been made to distribute the salt to the continuous phase. However, the present invention relates to the affinity between the salt and the polymer and the arrangement of the salt. Paying attention to the above configuration, reducing the environmental dependency (temperature dependency + humidity dependency) of electrical resistance while maintaining a sufficiently low resistance value, and reducing the increase in resistance during continuous energization Made possible.
In particular, in the present invention, a salt having a high degree of ion dissociation and a high conductivity is used, and even if an electric field is continuously applied, the salt is hardly transferred out of the system. Without greatly increasing the value, excellent conductivity can be obtained with a small amount of a salt having excellent conductivity. Therefore, the influence on other physical properties such as compression set and hardness can be reduced as much as possible.
[0015]
The phase structure of the polymer composition such as the continuous phase and the discontinuous phase can be observed, for example, with a phase mode of an atomic force microscope (AFM) type scanning probe microscope (SPM).
[0016]
  In the first invention,Two phases, the first discontinuous phase and the second discontinuous phase, are provided as the discontinuous phase, and the salt is hardly added to the second discontinuous phase and the continuous phase.
  And the polymer of each said phaseIs a polymer constituting the continuous phase acrylonitrile butadiene rubber (NBR),the aboveFirstDiscontinuousThe polymer constituting the phase is a polyoxyalkylene copolymer or epihalohydrin polymer, the polymer constituting the second discontinuous phase is ethylene propylene diene copolymer rubber (EPDM),The affinity with the salt is first discontinuous phase> continuous phase> second discontinuous phase, and the electric resistance value (volume resistivity) of each phase is the first discontinuous phase.<Continuous phase<Second discontinuous phaseTheThe affinity between the polymer of each phase and the salt is evaluated based on the volume resistivity described later of the polymer of each phase and the volume resistivity of the polymer of each phase in a state including a salt, and these volume resistivity is low. It can be said that the affinity between the polymer and the salt is high.
  By setting it as the said structure, the ratio of the 1st discontinuous phase in which the dissociable salt is unevenly distributed can be suppressed, without impairing electroconductivity very much. As a result, a low volume resistivity can be maintained as a whole composition even if the amount of dissociable salt is reduced.
  Preferably, the first discontinuous phase is present so as to surround the second discontinuous phase..
[0017]
YangWhen the volume resistivity of the polymer constituting the first discontinuous phase in which salts dissociable into ions and anions are unevenly distributed is R1, and the volume resistivity of the polymer constituting the continuous phase is R2, 2.3 ≦ log_TenR2-log_TenIt is sufficient if R1 ≦ 4.4.
  This is because if the above value is less than 2.3, a salt that can be dissociated into the continuous phase may be easily transferred. On the other hand, if the above value is larger than 4.4, it is difficult to realize low resistance as a whole. Moreover, the volume resistivity here is a volume resistivity of only the polymer containing no salt.
[0018]
NonThe weight ratio of the polymer constituting the continuous phase (total weight of the polymer constituting the first discontinuous phase and the second discontinuous phase) to the polymer constituting the continuous phase is (polymer constituting the discontinuous phase: continuous phase) It is preferable that it is (the polymer which comprises) = (20:80)-(45:55).
  If the blending ratio of the polymer constituting the discontinuous phase is less than the above range, the volume fraction of the discontinuous phase is too low, so the volume resistivity of the entire composition, or a roller or belt molded from the composition, etc. The resistance value cannot be lowered sufficiently. On the other hand, if the blending ratio of the polymer constituting the continuous phase is less than the above range, even if a technique such as dynamic crosslinking is used, it cannot be present as the continuous phase.
  In the present invention, the electric resistance value can be controlled to some extent by changing the ratio of the continuous phase and the discontinuous phase while keeping the blending amount of the dissociable salt fixed. If dynamic crosslinking is used, a relatively high fraction component can be brought into the discontinuous phase, and the ratio of the polymer constituting the discontinuous phase can be increased.
  In addition, the volume fraction of the said continuous phase, a 1st discontinuous phase, and a 2nd discontinuous phase is made into the continuous phase> 2nd discontinuous phase> 1st discontinuous phase.
[0019]
  The salt capable of dissociating into a cation and an anion is blended at a ratio of 0.01 parts by weight or more and 20 parts by weight or less with respect to 100 parts by weight of all polymer components.is doing.
  This is because if the amount is smaller than 0.01 parts by weight, a sufficient effect of reducing the electric resistance cannot be obtained. If the amount is larger than 20 parts by weight, the cost is increased. This is because it becomes difficult to obtain. In addition, More preferably, it is 0.2 to 10 weight part, More preferably, it is 0.4 to 6 weight part.
[0020]
The salt dissociable into a cation and an anion was measured in a propylene carbonate (PC) / dimethyl carbonate (DME) mixed solvent (volume fraction 1/2) at a salt concentration of 0.1 mol / l at 25 ° C. The conductivity is 2.3 mS / cm or more, preferably 3.5 mS / cm or more. This conductivity is proportional to the concentration of dissociated ions and their mobility. In addition, although the said electrical conductivity is so preferable that it is large, the upper limit of the electrical conductivity of the salt which exists actually is about 4.5 mS / cm.
Such a range of salts includes CF_ThreeSO_ThreeLi, C_FourF₉SO_ThreeLi, (CF_ThreeSO₂)₂NLi, (C₂F₅SO₂)₂NLi, (C_FourF₉SO₂) (CF_ThreeSO₂) NLi, (FSO₂C₆F_Four) (CF_ThreeSO₂) NLi, (C₈F₁₇SO₂) (CF_ThreeSO₂) NLi, (CF_ThreeCH₂OSO₂)₂NLi, (CF_ThreeCF₂CH₂OSO₂)₂NLi, (HCF₂CF₂CH₂OSO₂)₂NLi, ((CF_Three)₂CHOSO₂)₂NLi, (CF_ThreeSO₂)_ThreeCLi, (CF_ThreeCH₂OSO₂)_ThreeCLi, LiPF₆Etc.
[0021]
When a salt having a high conductivity as described above is used, a very low electric resistance value can be obtained with a small amount of addition. On the other hand, when such a salt with a high conductivity is used, the salt is particularly in the system. It becomes easy to move. Therefore, when the salt having high conductivity is not used to suppress the salt migration of the present invention, the resistance increase during continuous use tends to be significantly larger than that of the salt having low conductivity. Therefore, when a salt with good conductivity is used, particularly when the structure of the present invention is configured to suppress the salt migration, a remarkable effect can be exhibited.
[0022]
Further, as the salt capable of dissociating into the cation and the anion, a salt having an anion having a fluoro group and a sulfonyl group is preferably used. In such a salt, since functional groups such as a fluoro group and a sulfonyl group have electron withdrawing properties, anions are more stabilized and ions have a higher degree of dissociation. Thereby, a very low electric resistance value can be obtained with a small amount of addition.
[0023]
  The anion having a fluoro group and a sulfonyl group is an ion selected from at least one of the group consisting of a bis (fluoroalkylsulfonyl) imide ion, a tris (fluoroalkylsulfonyl) methide ion, and a fluoroalkylsulfonic acid ion. Is preferred. As a result, environmental dependency such as volume resistivity can be improved, the degree of dissociation is very large, and the EO-PO-AGE copolymerA polyoxyalkylene copolymer such asEpichlorohydrin rubberConsist ofIt is also preferable from the viewpoint of high compatibility with the polymer constituting the discontinuous phase. In particular, when a salt composed of bis (fluoroalkylsulfonyl) imide ion or tris (fluoroalkylsulfonyl) methide ion is used, environmental dependency such as volume resistivity can be extremely reduced..
[0024]
The cation of the salt having an anion having a fluoro group and a sulfonyl group is preferably an alkali metal, group 2A, transition metal or amphoteric metal cation. Alkali metals are particularly preferable because they have a low ionization energy and can easily form stable cations. In addition to the metal cation, a salt having a cation represented by the following chemical formula (Chemical Formula 1, Chemical Formula 2) may be used. Where R₁~ R₆Are each an alkyl group having 1 to 20 carbon atoms or a derivative thereof;₁~ R_FourAnd R_FiveAnd R₆May be the same or different. Among these, R₁~ R_FourOf which a trimethyl-type quaternary ammonium cation is composed of a methyl group and the other one is an alkyl group having 7 to 20 carbon atoms or a derivative thereof. It is particularly preferable because the positive charge on the atom can be stabilized and the compatibility with the polymer can be improved by other alkyl groups or derivatives thereof. In the cation of the chemical formula 2, R_FiveOr R₆Since it is easier to stabilize the positive charge on the nitrogen atom when it has an electron donating property, it is preferably a methyl group or an ethyl group. In this way, by stabilizing the positive charge on the nitrogen atom, the stability as a cation can be increased, and the salt can have a higher degree of dissociation and thus excellent conductivity imparting performance.
[0025]
[Chemical 1]

[0026]
[Chemical 2]

[0027]
For the reasons described above, salts having an anion having a fluoro group and a sulfonyl group are alkali metal salts of bis (trifluoromethanesulfonyl) imide, alkali metal salts of tris (trifluoromethanesulfonyl) methide, alkali of trifluoromethanesulfonic acid. Most preferably, the salt is selected from at least one of the group consisting of metal salts.
[0028]
Salts having anions consisting of bis (fluoroalkylsulfonyl) imide ions and tris (fluoroalkylsulfonyl) methide ions, especially bis (trifluoromethanesulfonyl) imide lithium, have been used in the past because they are stable even at very high temperatures. Unlike lithium perchlorate and perchloric acid quaternary ammonium salts, etc., there is no need for measures such as making them explosion-proof. From this point, the manufacturing cost can be reduced and the safety can be ensured, which is very good.
[0029]
  Salts that can dissociate into cations and anionsNumber averageMolecular weight(Mn)Low molecular weight polyether compounds and low molecular weight polar compounds of 10,000 or lessIs a conductive plasticizerIt is preferable that it is mix | blended without the medium which consists of. When such a medium is used, there is a case where the electric resistance value increases greatly when used continuously for a long time, or the medium precipitates together with ions, and the photosensitive member is likely to be contaminated.
  A known method can be used as a method of blending a dissociable salt without using the above medium. For example, after dry blending with a Henschel mixer, tumbler, etc., a blend containing a dissociable salt and polymer is melt-mixed with a single or twin screw extruder, Banbury mixer, kneader, etc. I can do it. In addition, when a dissociable salt is blended at a high temperature in a polymer system of a thermoplastic resin or a thermoplastic elastomer, it may be used under an inert gas atmosphere such as nitrogen for the purpose of preventing deterioration of the polymer, etc. Mixing (mixing) can also be performed.
[0030]
  Since the conductive polymer composition of the present invention can impart moderate elasticity and the like.,As vulcanized rubber compositionYes.
[0031]
  The polymer constituting the first discontinuous phase in which the salt capable of dissociating into a cation and an anion is unevenly distributed is an ether bond.TogetherFurther, since the cation generated from such a salt can be strongly stabilized, the polyoxyalkylene copolymer is used because the affinity between the salt and the polymer can be increased.OrEpihalohydrin polymersー andHaveThe The polymer constituting the discontinuous phase (first discontinuous phase) in the second invention is a polyoxyalkylene copolymer.
  Thus, by increasing the affinity between the polymer constituting the first discontinuous phase and the salt, the resistance value of the entire composition can be effectively reduced, and the precipitation of the salt out of the system and the continuous An increase in resistance value during use can be prevented.
  Specifically, it is preferable to use ethylene oxide-propylene oxide-allyl glycidyl ether copolymer (EO-PO-AGE copolymer) and / or epichlorohydrin rubber as the polymer constituting the first discontinuous phase. . As epichlorohydrin rubber, epichlorohydrin-ethylene oxide copolymer, epichlorohydrin-ethylene oxide-allyl glycidyl ether copolymer, epichlorohydrin-ethylene oxide-propylene oxide-allyl glycidyl ether copolymer, epichlorohydrin-ethylene oxide-propylene oxide copolymer And epichlorohydrin-allyl glycidyl ether copolymer.
  In addition, a polyethylene oxide block polyamide copolymer and a polyether ester amide copolymer also have high affinity with the salt used in the present invention, and are preferably used as a polymer constituting the first discontinuous phase.
[0032]
When the EO-PO-AGE copolymer is used, the copolymerization ratio can be set so that the volume resistivity can be reduced while maintaining the physical properties (compression set, hardness) of the composition. In the copolymer, the ethylene oxide ratio is preferably 55 mol% or more and 95 mol% or less. Ionic conductivity is exhibited because oxonium ions and metal cations in the polymer (for example, cations such as lithium ions in the added salt) are stabilized by ethylene oxide units and propylene oxide units. , By being transported by the segmental motion of the molecular chain of that part. In general, the ethylene oxide unit has higher stability than the propylene oxide unit. Therefore, a higher ratio of the ethylene oxide unit can stabilize more ions and realize a lower resistance.
[0033]
UpThe polymer constituting the continuous phase is acrylonitrile butadiene rubber (NBR), and among them, low nitrile NBR and / or medium / high nitrile NBR, or polyester-based thermoplastic elastomer is preferable.. ThisAs a result, the resistance value as a whole can be made as low as possible, and further, it is possible to prevent the dissociable salt from moving out of the composition and the resistance increase during continuous energization. In addition, CommunicatingAs a material of the continuation phase, the electrical resistance value is low to some extent and the Tg is low, so the temperature dependence of viscoelasticity near room temperature is small, thereby reducing the environmental dependence of volume resistivity. Nitrile NBR and the like are particularly preferable. The Tg of these polymers is -40 ° C or lower, more preferably -50 ° C or lower.
[0034]
YangThe second discontinuous phase in which the salt dissociable into ions and anions is not unevenly distributed is ethylene propylene diene copolymer rubber (EPDM) which is a low polarity rubber. Thereby, ozone resistance can be provided to a composition. For example, even when used for a conductive member or the like used in an image forming apparatus, ozone resistance can be secured against ozone generated in the apparatus.
  Furthermore, in order to reduce the temperature dependence of the viscoelasticity of the entire system near room temperature and to reduce the environmental dependence of the electrical resistance value, not only the polymer used for the continuous phase but also the polymer used for the second discontinuous phase. However, those having a lower Tg are preferred. The same applies to the polymer used for the first discontinuous phase. The Tg of these polymers is preferably −40 ° C. or lower, more preferably −50 ° C. or lower.
[0035]
In the present invention, a part of the ions generated from the salt to be added can be converted into a single ion using an anion adsorbent or the like to stabilize the conductivity or improve the conductivity when added in a small amount. As an anion adsorbent, synthetic hydrotalcite mainly composed of Mg and Al, inorganic ion exchangers such as Mg-Al, Sb, and Ca, and ion sites that fix anions in the chain (co-current). ) Known compounds such as polymers are useful. Specifically, synthetic hydrotalcite (manufactured by Kyowa Chemical Industry Co., Ltd., trade name Kyoward 2000, Kyoward 1000), anion exchange ion exchange resin (manufactured by Nippon Nensui Co., Ltd., trade name Dyanon DCA11), etc. Is mentioned.
[0036]
When a polymer containing halogen such as chlorine is used as the polymer, it is preferable to incorporate an acid acceptor such as hydrotalcite in order to prevent deterioration of the polymer due to dehydrochlorination reaction and rusting of the kneader. In the case of synthetic hydrotalcite, the blending amount is 1 to 15 parts by weight, preferably 3 to 12 parts by weight, based on 100 parts by weight of the halogen-containing polymer.
[0037]
As the vulcanizing agent to be added, sulfur is particularly preferable because low electrical resistance can be realized. In addition to sulfur and organic sulfur-containing compounds, peroxides can be used, and these can be used in combination. In particular, when EPDM or EPM is used as the low-polar rubber forming the second discontinuous phase, the peroxide phase can effectively vulcanize the phase composed of these rubbers.
Examples of the organic sulfur-containing compound include tetraethylthiuram disulfide and N, N-dithiobismorpholine. Examples of the peroxide include dicumyl peroxide and benzoyl peroxide. Of these, when foaming is performed together with vulcanization, it is preferable to use sulfur from the viewpoint of improving the balance between the vulcanization speed and the foaming speed. The addition amount of the vulcanizing agent is 0.5 to 5 parts by weight, preferably 1 to 3 parts by weight, based on 100 parts by weight of the polymer component.
[0038]
Moreover, you may mix | blend a vulcanization accelerator and can use inorganic promoters, such as slaked lime, magnesia (MgO), and risurge (PbO), and the organic promoter described below.
Examples of organic accelerators include thiazoles such as 2-mercapto-benzothiazole and dibenzothiazyl disulfide, sulfenamides such as N-cyclohexyl-2-benzothiazylsulfenamide, tetramethylthiuram monosulfide, and tetramethylthiuram. Thiurams such as disulfide, tetraethylthiuram disulfide, and dipentamethylenethiuram tetrasulfide, and thioureas can be used in appropriate combination.
The vulcanization accelerator is preferably 1 part by weight or more and 5 parts by weight or less, and more preferably 2 parts by weight or more and 4 parts by weight or less with respect to 100 parts by weight of the polymer component.
[0039]
Further, a vulcanization acceleration aid may be blended, and examples thereof include metal oxides such as zinc white, fatty acids such as stearic acid, oleic acid, and cottonseed fatty acid, and other conventionally known vulcanization acceleration aids.
You may mix | blend a chemical foaming agent in the ratio of 3 to 12 weight part with respect to 100 weight part of polymer components for provision of a softness | flexibility etc. In addition, you may mix | blend softeners, such as oil, anti-aging agent, etc.
Further, for the purpose of improving the mechanical strength, a filler can be blended as necessary within a range not impairing the electrical characteristics and other physical properties. Examples of the filler include powders such as silica, carbon black, clay, talc, calcium carbonate, magnesium carbonate, and aluminum hydroxide. The filler is preferably 60 parts by weight or less with respect to 100 parts by weight of the polymer.
[0040]
The conductive polymer composition of the present invention is more preferably non-chlorine or non-bromine without using a salt having chlorine or bromine.
Specifically, a composition that does not contain chlorine or bromine as a polymer, and does not use a salt containing chlorine or bromine such as lithium perchlorate, sodium perchlorate or quaternary ammonium perchlorate, By using a non-chlorine or non-bromine composition as a whole, there is no risk of corroding, rusting or contaminating the metal surface such as the shaft of the conductive roller. Furthermore, an incineration process after use can be performed very easily, and an environmentally friendly composition can be obtained.
[0041]
The conductive polymer composition of the present invention described above was measured at a measurement temperature of 70 ° C., a measurement time of 22 to 24 hours, and a compression ratio of 25% in the permanent strain test method of vulcanized rubber and thermoplastic rubber described in JIS K6262. The magnitude of the compression set is preferably 30% or less. This is because when the ratio is larger than 30%, the dimensional change becomes too large when the composition is molded and used as a conductive member such as a roller or a belt, which is not suitable for practical use. In addition, More preferably, it is 25% or less, and it is so good that it is small.
[0042]
Further, the volume resistivity described in JIS K6911 measured under an applied voltage of 100 V is 10^10.0It is preferably less than [Ω · cm]. This has a volume resistivity of 10^10.0If it is larger than Ωcm, good conductivity cannot be obtained when a conductive member or the like is used, and it is not suitable for practical use. In addition, when the composition is molded into a roller, a belt, or the like, the efficiency of transfer, charging, toner supply, etc. is likely to decrease. The volume resistivity is 10^4.0Ωcm or more 10^9.5More preferably, it is Ωcm or less.
[0043]
Furthermore, in an environment of 23 ° C. and relative humidity of 55%, a volume resistivity ρ when a constant voltage of 1000 V is continuously applied to a sample having a thickness of 0.25 mm for 5 hours._V[Ω · cm] is measured, and volume resistivity increase Δlog_Tenρ_V= Log_Tenρ_V(T = 5 hr.)-Log_Tenρ_VThe value of (t = 0 hr.) Is preferably 0.5 or less. This is because if the index value of the volume resistivity increase is greater than 0.5, the resistance increase during continuous use increases when molded into a conductive member or the like, which may impair practical use. is there.
[0044]
Furthermore, the volume resistivity ρ under conditions of 15% relative humidity at 10 ° C. and 90% relative humidity at 32.5 ° C._V[Ω · cm] is measured and the volume resistivity is dependent on the environment Δlog_Tenρ_V= Log_Tenρ_V(10 ° C relative humidity 15%)-log_Tenρ_VThe value of (32.5 ° C. relative humidity 90%) is 1.7 or less, preferably 1.4 or less, more preferably 1.2 or less, and most preferably 1.1 or less.
This is because when the index value of the volume dependency of the environmental dependency is larger than 1.7, when the conductive material is molded into a conductive member or the like, the resistance value changes greatly due to the environmental change and requires a larger power source. This is because the power consumption and product cost of the image forming apparatus using the conductive member increase.
[0045]
  The present inventionIs aboveThe present invention provides a conductive member which is molded using the conductive polymer composition described above and is used as a conductive roller or a conductive belt.
[0046]
DETAILED DESCRIPTION OF THE INVENTION
  Embodiments of the present invention will be described below.
  FIG. 1 is a schematic diagram showing the structure of an ion conductive polymer composition according to a first embodiment of the present invention that forms a conductive layer. The ion conductive polymer comprises a continuous phase 1, a first discontinuous phase 2, It consists of the second discontinuous phase 3 and the three phases have a sea-island structure. The first discontinuous phase 2 and the second discontinuous phase 3 exist substantially uniformly in the continuous phase 1, and the first discontinuous layer 2 exists so as to surround the second discontinuous phase 3.
  The second discontinuous phase 3 is a second embodiment to be described later.ThenExistenceNot letting.
[0047]
  FIG. 2 shows the morphology (one side of 10 μm) of the conductive polymer composition observed in a phase mode with an atomic force microscope (AFM) scanning probe microscope (SPM). In FIG. 2, continuous phase 1 exhibits the lightest color, first discontinuous phase 2 exhibits the darkest color, and second discontinuous phase 3 exhibits a moderate color density.TheYes. In the figure, the dark portion has a high elastic modulus, and the light portion has a low elastic modulus.
  In addition, as shown in FIG.>Second discontinuous phase 3>The first discontinuous phase 2 is obtained.
[0048]
In order to exhibit the sea-island structure as shown in FIG. 1 and FIG. 2, the type and amount of the polymer in each phase are defined, and the amount of salt to be added and the addition method are defined.
To the ion conductive polymer composition, 0.01 to 20 parts by weight of a salt capable of dissociating into a cation and an anion is added with respect to 100 parts by weight of the total polymer, and the first discontinuous phase 2 is added. In the second discontinuous phase 3 and the continuous phase 1, almost no salt is added.
[0049]
The polymer of the first discontinuous phase 2 has a higher affinity for the dissociable salt than the polymer constituting the continuous phase 1, and the polymer constituting the continuous phase 1 does not add a dissociable salt. The affinity with the dissociable salt is higher than that of the polymer constituting the second discontinuous phase 3. That is, the affinity of each phase with the polymer salt is such that first discontinuous phase 2> continuous phase 1> second discontinuous phase 3.
[0050]
Specifically, as shown in Example 2 described later, in the first embodiment, for example, an EO-PO-AGE copolymer (EO: PO: AGE =) is used as a polymer constituting the first discontinuous phase 2. 90: 4: 6) 10 parts by weight, 63 parts by weight of low nitrile NBR as the polymer constituting the continuous phase 1, and low polarity as the polymer constituting the second discontinuous phase 3 with almost no dissociable salt added 27 parts by weight of EPDM, which is an ozone resistant rubber, is used. That is, the affinity with the dissociable salt is EO-PO-AGE copolymer> low nitrile NBR> EPDM.
[0051]
The volume resistivity of the EO-PO-AGE copolymer of the first discontinuous phase 2 is R1, the volume resistivity of the low nitrile NBR of the continuous phase 1 is R2, and the volume resistivity of the EPDM of the second discontinuous phase 3 is R3. And log_TenR1 is 7.9, log_TenR2 is 10.2, log_TenR3 is 14.8, and the value of (logR2-logR1) is 2.3. The weight ratio of the polymer constituting the first and second discontinuous phases 2 and 3 to the polymer constituting the continuous phase 1 is 37:63.
[0052]
  1.1 parts by weight of lithium-bis (trifluoromethanesulfonyl) imide, which is a salt having an anion having a fluoro group and a sulfonyl group, as a salt dissociable into a cation and an anion added to the conductive polymer ing. This salt has a conductivity of 4.0 mS / cm measured in a PC / DME mixed solvent (volume fraction 1/2) at a salt concentration of 0.1 mol / l at 25 ° C. Also,Number averageMolecular weight(Mn)Low molecular weight polyether compounds and low molecular weight polar compounds of 10,000 or lessIs a conductive plasticizerIt mix | blends without the medium which consists of.
  Lithium-bis (trifluoromethanesulfonyl) imide is disclosed in JP-B-1-38781 (application by Amber Co., Ltd.) or JP-A-9-173856 (application from Noguchi Laboratory and Asahi Kasei Corporation). Or Japanese Patent No. 3117369, Japanese Patent Application Laid-Open No. 11-209338 (Application of Central Glass Co., Ltd.), or Japanese Patent Application Laid-Open No. 2000-86617, Japanese Patent Application Laid-Open No. 2001-139540 (Application of Kanto Denka Kogyo Co., Ltd.) ), Or those synthesized by a conventionally known method such as JP-A-2001-288193 (filed by Morita Chemical Co., Ltd.).
  Lithium tris (trifluoromethanesulfonyl) methane is disclosed in US Pat. No. 5,554,664, or JP 2000-219692 (filed by Noguchi Laboratory and Asahi Kasei Corporation), or JP 2000- The one synthesized by a conventionally known method such as 226392 (Kanto Denka Kogyo Co., Ltd. application) was used.
[0053]
The conductive polymer composition contains 9 parts by weight of carbon black as a filler, 5 parts by weight of zinc oxide, 1 part by weight of stearic acid, 1.5 parts by weight of powdered sulfur as a vulcanizing agent, and two types of vulcanization accelerators. Each consists of a vulcanized rubber composition blended with 1.5 parts by weight and 0.5 parts by weight.
[0054]
FIG. 3 shows a conductive roller 10 having a conductive layer 11 formed from the conductive polymer composition. The conductive roller 10 includes a cylindrical metal core 12 having conductivity and the conductive layer 11 on the surface side of the core 12, and the core 12 is provided in a hollow portion of the cylindrical conductive layer 11. Press-fit and install.
[0055]
The conductive roller 10 is manufactured by the following method.
First, a dissociable salt and an EO-PO-AGE copolymer were kneaded at 60 ° C. for 3 minutes using a kneader, and low nitrile NBR, EPDM, and other various compounding agents were added to the kneaded product obtained here. It mix | blends and again knead | mixes with an open roll, a closed kneader, etc. at 60 degreeC for 4 minutes, and produces a conductive polymer composition.
[0056]
This conductive polymer composition is put into a single screw extruder having a diameter of 60 mm, extruded into a hollow tube shape at 60 ° C. and preformed, and the raw rubber tube is cut into a predetermined size to obtain a preform. When this preform is put into a pressurized steam vulcanizing can and foamed, the chemical foaming agent is gasified and foamed, and vulcanized at a temperature at which the rubber component crosslinks (15 to 70 minutes at 160 ° C.). Obtained vulcanized rubber tube.
Vulcanization conditions are measured with a curast meter or the like, and are appropriately adjusted with a 95% torque rise time t95 [minute] as a guide.
In order to reduce the photoreceptor contamination and compression set, it is desirable to set the conditions so that a sufficient vulcanization amount can be obtained.
[0057]
After preparing the core metal 12 and applying the hot melt adhesive to the outer peripheral surface thereof, the core metal is inserted into the vulcanized rubber tube obtained above, heated and bonded, and then the surface is polished to form the conductive layer 11. Finished to the target dimensions. The dimensions of the conductive layer 11 of the conductive roller 10 are an inner diameter of 6 mm, an outer diameter of 14 mm, and a length of 218 mm.
[0058]
The conductive layer 11 has a compression set value of 17% measured at a measurement temperature of 70 ° C. for a measurement time of 24 hours in the permanent strain test method for vulcanized rubber and thermoplastic rubber described in JIS K6262, and an applied voltage of 100V. The volume resistivity described in JIS K6911 measured under^9.0[Ω · cm].
[0059]
Further, the conductive polymer composition described in Example 2, for example, constituting the conductive layer of the conductive roller 10 has a volume resistivity of 10 at an applied voltage of 100V.^9.0Volume resistivity ρ when a constant voltage of 1000 V is continuously applied for 5 hours to a sample having a thickness of 0.25 mm in an environment of 23 ° C. and a relative humidity of 55%._V[Ω · cm] is measured, and volume resistivity increase Δlog_Tenρ_V= Log_Tenρ_V(T = 5 hr.)-Log_Tenρ_V(T = 0 hr.) Is 0.08, and volume resistivity ρ under conditions of 10 ° C. relative humidity 15%, 32.5 ° C. relative humidity 90%_V[Ω · cm] is measured and the volume resistivity is dependent on the environment Δlog_Tenρ_V= Log_Tenρ_V(10 ° C relative humidity 15%)-log_Tenρ_VThe value of (32.5 ° C. relative humidity 90%) is set to 0.8.
[0060]
The conductive layer 11 of the conductive roller 10 manufactured by the above method includes the continuous phase 1, the first discontinuous phase 2, and the second discontinuous phase 3, and the first discontinuous phase 2 and the second discontinuous phase 3. To surround. As described above, the high-performance salt that can control the morphology and reduce the resistance value in a small amount is unevenly distributed in the first discontinuous phase 2 mainly composed of the EO-PO-AGE copolymer. It is possible to obtain a low electrical resistance value necessary for practical use while preventing the salt from moving out of the product when added and the resistance increase during continuous energization.
[0061]
Therefore, while maintaining low electrical resistance, changes in the electrical resistance due to the environment and changes due to continuous use are reduced, and variations in the electrical resistance due to the roller parts are reduced, so that stable and good images can be formed. A gentle conductive roller can be obtained. Therefore, it is suitable for a developing roller, a charging roller, a transfer roller, and the like. In particular, it is suitable as a conductive roller for color copiers or color printers that require high image quality.
A foaming agent is blended, the expansion ratio is 100% or more and 500% or less, preferably 150% or more and 300% or less, and the hardness measured with a type E durometer described in JIS K6253 is 60 degrees or less, preferably 40 degrees. It can also be set as the foaming roller which has the following foaming layers.
[0062]
The conductive layer 11 is provided with a second discontinuous phase 3 in which almost no salt is distributed, and the second discontinuous phase 3 is surrounded by the first discontinuous phase 2 in which salt is unevenly distributed. Therefore, the volume fraction of the first discontinuous phase 1 in which the salt is unevenly distributed can be suppressed without significantly impairing the conductivity. Thereby, even if the addition amount of the salt and the polymer of the first discontinuous phase 1 that actively distributes the salt is reduced, a low volume resistivity and a product resistance value of the roller can be obtained as a whole. In addition, since the salt having an anion having a fluoro group and a sulfonyl group used as a salt capable of dissociating into a cation and an anion is expensive, the increase in cost can be suppressed by reducing the amount of the salt added. be able to.
[0063]
  4 and 5 arereferenceShowing an embodiment,Of the reference embodimentThe form which used the electroconductive belt 13 formed using an electroconductive polymer composition as a transfer belt is shown.Needless to say, the conductive belt 13 shown in FIG. 4 may be used by using the conductive polymer composition of the first embodiment.
  The conductive belt 13 is stretched by two pulleys 14 and carries and conveys a sheet material 16 such as paper on a linear portion 15 on the upper side of the rotating conductive belt 13. The toner image formed above is transferred to the sheet material 16.
[0064]
Although the said electroconductive belt 13 is not limited only to such a form, it consists only of the electroconductive layer 21 formed from the electroconductive polymer composition of one layer of seamless belt shape. As shown in FIG. 5, the conductive layer 21 is composed of a single continuous phase 1 ′ and a single first discontinuous phase 2 ′. The continuous phase 1 ′ and the first discontinuous phase 2 ′ It has a sea-island structure. Only the first discontinuous phase 2 'has a salt dissociable into a cation and an anion, and the polymer constituting the first discontinuous phase 2' can be dissociated more than the polymer constituting the continuous phase 1 '. It has a high affinity with various salts.
[0065]
Specifically, 30 parts by weight of a resin-type antistatic agent made of a polyethylene oxide block nylon 12 copolymer is used as a polymer constituting the first discontinuous phase 2 ′ in which dissociable salts are unevenly distributed, and the continuous phase 1 ′ is used. As a constituent polymer, 100 parts by weight of a polyester-based thermoplastic elastomer composed of a soft segment made of polyether and a hard segment made of polyester is used.
[0066]
If the volume resistivity of the resin-type antistatic agent constituting the first discontinuous phase is R1, and the volume resistivity of the polyester thermoplastic elastomer constituting the continuous phase is R2, log._TenR1 is 9.0, log_TenR2 is 13.4 and (log_TenR2-log_TenThe value of R1) is 4.4. The weight ratio of the polymer constituting the first discontinuous phase 2 'to the polymer constituting the continuous phase 1' is 23:77.
[0067]
  As a salt dissociable into a cation and an anion, 1.5 parts by weight of lithium-bis (trifluoromethanesulfonyl) imide, which is a salt having an anion having a fluoro group and a sulfonyl group, is used. This salt has a conductivity of 4.0 mS / cm measured at a salt concentration of 0.1 mol / liter at 25 ° C. in a PC / DME mixed solvent (volume fraction 1/2), and has a molecular weight of 10,000 or less. Low molecular weight polyether compounds and low molecular weight polar compoundsIs a conductive plasticizerIt mix | blends without the medium which consists of.
[0068]
  Conductive belt13Is manufactured by the following method.
  The detachable salt and the resin-type antistatic agent are dry blended using a tumbler. This dry blend is immediately fed into a twin screw extruder. After kneading at 170-210 ° C. for 2 minutes, the mixture is cooled and pelletized. The pellets of the kneaded product obtained here are dry-blended with polyester thermoplastic elastomer pellets in the same manner as described above, and again kneaded at 210-270 ° C. for 2 minutes using a twin-screw extruder, cooled, and electrically conductive. A pellet of the functional polymer composition is prepared. The pellets of the conductive polymer composition are formed into a belt shape by an extruder for resin.
[0069]
  Conductive belt13Has a volume resistivity of 10 described in JIS K6911 measured under an applied voltage of 100V.^9.6[Ω · cm].
[0070]
  Also conductive belt13Is a volume resistivity ρ when a constant voltage of 1000 V is continuously applied to a sample having a thickness of 0.25 mm in an environment of 23 ° C. and a relative humidity of 55% for 5 hours._V[Ω · cm] is measured, and volume resistivity increase Δlog_Tenρ_V= Log_Tenρ_V(T = 5 hr.)-Log_Tenρ_V(T = 0 hr.) Is set to 0.36, and the volume resistivity ρ under the conditions of 10 ° C. relative humidity 15%, 32.5 ° C. relative humidity 90%._V[Ω · cm] is measured and the volume resistivity is dependent on the environment Δlog_Tenρ_V= Log_Tenρ_V(10 ° C relative humidity 15%)-log_Tenρ_VThe value of (32.5 ° C. relative humidity 90%) is 1.4.
[0071]
  The conductive belt 13 includes a conductive layer 21 in which a salt that can be dissociated into a cation and an anion is unevenly distributed in the first discontinuous phase 2 ′, and a salt that can reduce the resistance value with a small amount as a salt to be added. In addition, the polymer used for each phase is appropriately selected, so that it is necessary for practical use while preventing the salt from moving out of the system when an electric field is applied and the increase in resistance during continuous energization. A low electrical resistance value can be obtained. Moreover, while having a moderate flexibility in the thickness direction, it is difficult to stretch in the length direction..
[0072]
In the above-described embodiment, the case where the conductive belt of the present invention is used as a transfer belt has been described in detail. However, for example, an intermediate transfer belt, a fixing belt, a developing belt, and a conveyance belt used in an image forming apparatus may be used. Can be used. In particular, when a white belt is used, toner adhesion can be easily visually checked, so that it is suitable for evaluation of cleaning performance and can be suitably used as an intermediate transfer belt.
[0073]
  In addition to the above embodiment, the polymer constituting the continuous phase, the polymer constituting the discontinuous phase, and the dissociable salt are:As long as it is within the scope of the present invention,As described above, various materials can be used. Various compounding materials can be changed as necessary to optimize the electrical characteristics according to the required performance. Various types and amounts of compounding materialsWithin the scope of the present invention.It can be set appropriately. Kneading can be performed by a method other than the above, and a conductive polymer composition can be produced and a conductive member can be formed by a conventionally known method.
[0074]
  Hereinafter, Examples of conductive members formed using the conductive polymer composition of the present invention,Reference examples,A comparative example will be described in detail.
  First, an example of a conductive roller,Reference examples andA comparative example will be described.
  Example 14. Reference Examples 1 and 2About Comparative Examples 1-5, each compounding material of Table 1 and Table 2 was kneaded, extruded, vulcanized, molded, and polished by the same method as in the above embodiment to produce a conductive roller. A conductive roller for a transfer roller equipped with a Laser Jet 4050 type laser beam printer manufactured by Hewlett-Packard Company was used.
[0075]
In parallel with this, the rubber removed from the kneader is extruded by a roller head extruder and formed into a sheet shape. After being vulcanized in a vulcanizer at 160 ° C for an optimal time, the thickness is about 2 mm. This was sliced to obtain a vulcanized rubber slab sheet for volume resistivity (volume resistivity value) evaluation. Tables 1 and 2 show the evaluation results obtained using these rollers and rubber slab sheets and various evaluations as rollers described later.
In measuring the resistance increase during continuous energization, a sliced slice having a thickness of about 0.25 mm was prepared and used in order to match the conditions with the example of the conductive belt.
[0076]
[Table 1]

[0077]
[Table 2]

[0078]
  (Example 14. Reference Examples 1 and 2)
  FirstAn EO-PO-AGE copolymer or epichlorohydrin rubber is used as the polymer constituting the discontinuous phase, and lithium-bis (trifluoromethanesulfonyl) imide or lithium-tris (which can be dissociated into a cation and an anion) (Trifluoromethanesulfonyl) methane was unevenly distributed. Using low nitrile NBR as the continuous phase,SecondEPDM was used as the discontinuous phase. A foaming roller was used except for Example 2.
[0079]
  (referenceExample3)
  Epichlorohydrin rubber (50 phr), NBR, calcium carbonate, hydrotalcite, zinc white and stearic acid were mixed and kneaded in a closed kneader preheated to 120 ° C. A thiourea crosslinking agent (vulcanizing agent 2) master batch of epichlorohydrin rubber (for 10 phr) prepared in advance while kneading and a crosslinking accelerator for the thiourea crosslinking agent (vulcanization accelerator 3) were added for dynamic crosslinking. Crosslinking proceeded while looking at the kneading torque chart, and kneading was once completed near the torque peak. Then, it cooled to 50 degreeC, sulfur, the vulcanization accelerator 1, and the vulcanization accelerator 2 were mixed with the kneader, and the dynamic crosslinking composition was obtained. This is described in Examples 1 to4. Reference Examples 1 and 2In the same manner as above, the tube was extruded and preformed, and the tube was cut and vulcanized at 160 ° C. for 10 to 70 minutes to obtain a conductive layer.
[0080]
(Comparative Examples 1-5)
Comparative Example 1 did not use a salt that can be dissociated into a cation and an anion. Comparative Examples 2 and 3 have a two-phase structure of a continuous phase composed of low nitrile NBR and a discontinuous phase composed of EPDM, and a salt that can dissociate into a cation and an anion is unevenly distributed in the continuous phase. Comparative Examples 4 and 5 had a structure of only one phase composed of one kind of polymer, and a salt capable of dissociating into a cation and an anion was added to the one phase. Comparative Examples 1 and 2 were foam rollers.
[0081]
  As the EO-PO-AGE copolymer or epichlorohydrin rubber, one previously kneaded with a dissociable salt was used. In the combined system of carbon black and EPDM, carbon black was previously kneaded into EPDM and used as a master batch.referenceExample2Then, carbon black was previously kneaded into NBR and used as a master batch. Vulcanization accelerator 1 was dibenzothiazyl disulfide, vulcanization accelerator 2 was tetramethylthiuram monosulfide, and blowing agent 1 was 4,4'-oxybis (benzenesulfonylhydrazide).
[0082]
The volume resistivity R1 of the polymer constituting the discontinuous phase in which salts dissociable into cations and anions are unevenly distributed, the volume resistivity R2 of the polymer constituting the continuous phase, and the salt dissociable into cations and anions The volume resistivity R3 of the polymer constituting the non-continuous phase not unevenly distributed was measured without adding salt.
For example, in Example 1 or Example 2, 100 parts by weight of ZSN8030, 9 parts by weight of Seest 3, 5 parts by weight of silver candy R, 1 part by weight of stearic acid 4931, 1.5 parts by weight of powdered sulfur, Noxeller DM The volume resistivity of a composition containing 1.5 parts by weight and 0.5 parts by weight of Noxeller TS was measured. During measurement, the applied voltage was 100 V, the measurement environment was 23 ° C., and the relative humidity was 55%.
[0083]
  In addition, for conductive rollers using urethane compositionsreferenceExamples and comparative examples will be described in detail.referenceExample4And about Comparative Examples 6-8, the conductive layer was produced using the material which consists of a mixing | blending of following Table 3 and Table 4, respectively.
[0084]
[Table 3]

[0085]
[Table 4]

[0086]
  (referenceExample4)
  Two kinds of polyether polyols 1 and 2 were used, and lithium-bis (trifluoromethanesulfonyl) imide, which is a salt dissociable into a cation and an anion, was used.
  PolyDBoth ether polyol 1 and polyether polyol 2 are PPG-based polyols, have the same hydroxyl value, and have almost the same basic structure. Therefore, they are uniformly compatible to form one phase.
  The continuous phase is composed of a liquid polybutadiene polymer (terminal isoazonate prepolymer 1) that has a fairly low affinity for salts, and log_TenR2 is 14.1.
  The discontinuous phase was composed of a PPG polyol having a relatively high affinity with the salt as described above. log_TenR1 is 11.1 and log_TenR2−log_TenR1 is 3.0.
  As described above, in the polyurethane composition obtained by reacting the isocyanate prepolymer and the polyol, the ratio of the discontinuous phase to the continuous phase is about 40:60.Become.
  Specifically, a conductive layer was produced as follows.
  After the polyether polyol 1 and the polyether polyol 2, the aromatic diamine, the antifoaming agent, the leveling agent, and the like are weighed, the mixture is stirred and uniformly mixed at room temperature using a rotary stirrer or the like. Thereafter, the mixture was degassed under reduced pressure. Similarly, the terminal isocyanate prepolymer defoamed under reduced pressure is mixed with the previously prepared mixed solution, stirred and defoamed again, and then poured into slabs for evaluating physical properties and various molds for producing conductive rollers. After pouring into the mold, heating is performed at 150 ° C. for 60 minutes, thereby causing a curing reaction and obtaining a desired slab or conductive roller.
  In addition, when used for a conductive roller, when a metal shaft is coated with a urethane primer, a mixture of the polyol-containing mixture and an isocyanate prepolymer is poured into a mold. good.
  As a primer for urethane, for example, a mixture of SBU polyol 0759 manufactured by Sumika Bayer Urethane Co., Ltd., and Sumijoule 44V20 in a weight ratio of 1: 2 is preferably used. .
  The volume resistivity of the urethane composition and its environmental dependency were measured using a 130 × 130 × 2 mm slab, but the resistance increase during continuous energization was 130 × 130 × 0.25 mm.
[0087]
  (Comparative Example 6-8)
  Comparative Examples 6 and 7 did not contain a dissociable salt. In Comparative Example 8, a PPG polyol (polyether polyol 1, 2) and a PPG prepolymer (terminal isocyanate prepolymer 2) were used, but a liquid polybutadiene prepolymer having a lower affinity for salt than PPG was not used. Basically, the composition is composed of only a phase having a relatively high affinity with a dissociable salt. BothreferenceExample4A conductive layer was prepared in the same manner as described above.
[0088]
(Measurement of volume resistivity)
It measured on the measurement sheet | seat produced as mentioned above on the constant temperature and humidity conditions of 23 degreeC relative humidity 55% using the ultra high resistance microammeter R-8340A made from Advantest Corporation. The measurement method was in accordance with the volume resistivity (volume resistivity) measurement method described in JIS K6911, and the applied voltage at the time of measurement was 100V. The common logarithm value is displayed in the table. In addition, for Examples and Comparative Examples of conductive belts, the obtained conductive belts were used as they were, and measurements were made in the same manner as described above at a total of 20 points of 4 points in the circumferential direction of the belt and 5 points in the longitudinal direction._Tenρ_VThe average value of [Ω.cm] is shown in the table.
[0089]
(Roller resistance value)
As shown in FIG. 6, the conductive layer 41 through the cored bar 42 is abutted and mounted on a φ30 aluminum drum 43 and connected to the + side of the power supply 44 in an atmosphere at a temperature of 23 ° C. and a relative humidity of 55%. The end of the conducting wire having resistance r (100Ω to 10 kΩ) was connected to one end surface of the aluminum drum 43 and the leading end of the conducting wire connected to the negative side of the power source 44 was connected to the other end surface of the conductive layer 41 to conduct electricity. The conductive roller 40 was indirectly rotated by applying a load F of 500 g to both ends of the core metal 42 and rotating the aluminum drum 43 while applying a voltage of 1000 V between the core metal 42 and the aluminum drum 43. At this time, resistance measurement was performed 36 times in the circumferential direction, and the average value was obtained. The value of the internal resistance was adjusted so that the significant figure of the measured value was as large as possible according to the level of the resistance value of the roller. In the apparatus of FIG. 6, when the applied voltage is E, the roller resistance value R is R = r × E / V−r, but the term of −r is regarded as very small this time, and R = r × E / V. The roller resistance value R was calculated from the detected voltage V applied to the internal resistance r. In the table, the average logarithmic value of the roller resistance value is used.
[0090]
  (Volume specific resistance environment dependence)
  Example / Comparative Example of Conductive Belt 10 ° C. Relative Humidity 15% (LL Environment), 32.Even in an environment of 5 ° C. and a relative humidity of 90% (HH environment), the volume resistivity of the conductive belt when 100 V was applied was measured in the same manner as described above.
  And, the environmental dependency of volume resistivity: Δlog_Tenρ_V(LL-HH) [Ω.cm] = log_Tenρ_V(10 ℃, 15% rh.)-Log_TenρV (32.According to the equation of 5 ° C., 90% rh.), Environmentally dependent numerical values are calculated and listed in Tables 5 and 6. It is not preferable that this value exceeds 1.7.
[0091]
(Roller resistance unevenness)
Using the apparatus shown in FIG. 6, in an atmosphere of 23 ° C. and 55% relative humidity, a load F of 500 g is applied to both ends of the metal core, and the conductive roller is rotated by rotating the aluminum drum at a rotation speed of 30 rpm. In this state, when an applied voltage of 1000 V was applied, the circumferential unevenness (ratio of (maximum value of electrical resistance in the circumferential direction / minimum value of electrical resistance in the circumferential direction)) within one circle was determined. The circumferential unevenness is 1.0 to 1.3, more preferably 1.0 to 1.2, and still more preferably 1.0 to 1.15.
[0092]
  (Resistance increase during continuous energization)
  By measuring roller resistance.
    [Examples 1 to4. Reference Examples 1-3], [Comparative Examples 1 to 5]
  A constant voltage of 1000 V was continuously applied to the roller for 96 hours in an environment of 23 ° C. and relative humidity of 55% in the same state as when the roller resistance value [Ω] was measured. At this time, the roller resistance value R (t = 0) immediately after voltage application and the roller resistance value R (t = 96 hr.) After application for 96 hours were measured in the same manner as described above, and these values were used. Resistance increase during continuous energization: Δlog_Ten R (t = 96-0hr.) [Ω] = log_Ten R (t = 96hr.)-Log_Ten R (t = 0) was calculated. Numerical values are shown in Tables 1-4. Since the rotation speed of the aluminum drum is 30 rpm and the diameter is 30 mmφ, the linear velocity during rotation is 94 mm / min.
[0093]
(Resistance increase during continuous energization)
By measuring volume resistivity.
A digital ultra-high manufactured by Advantest Corporation in a conductive belt or at a point with a slab of 0.25 mm in thickness in the same condition as when measuring volume resistivity in an environment of 23 ° C. and 55% relative humidity. A constant voltage of 1000 V was continuously applied for 5 hours using a resistance microammeter R-8340A. At this time, the volume resistivity ρ of the belt or slab immediately after voltage application_V(t = 0) and the volume resistivity ρ of the belt or slab after 5 hours application_VThe value of (t = 5 hr.) was measured in the same manner as described above, and using these values, the resistance increase during continuous energization: Δlog_Tenρ_V(t = 5-0hr.) [Ω.cm] = log_Tenρ_V(t = 5hr.)-log_Tenρ_V(t = 0) was calculated. Numerical values are shown in each table.
[0094]
(In-plane unevenness)
The measurement of the in-plane unevenness of the conductive belt is performed by dividing the maximum value of the 20 specific volume resistivity values obtained in one belt by the minimum value. The calculated values were calculated and listed in Tables 5 and 6. Thus, it can be seen that the belts in Examples and Comparative Examples are very uniform with almost no unevenness. On the other hand, this value can be about 2 to 10 for a carbon conductive belt, and about 100 for a large belt.
Regarding the in-plane unevenness of the volume resistivity of the rubber composition for the conductive roller and the urethane composition, Mitsubishi Chemical Co., Ltd. has a total of 20 points in the produced 130 × 130 × 2 mm slab: 5 points in length × 4 points in width. Measurement was performed using a Hiresta UP and URS type probe, and a value obtained by dividing the maximum value by the minimum value was calculated and described in each table.
[0095]
(Compression set)
Using the test piece obtained by cutting the conductive roller obtained above with a width of 10 mm parallel to the end face, according to the vulcanized rubber and thermoplastic rubber permanent strain test method described in JIS K6262, a measurement temperature of 70 ° C., a measurement time The measurement was performed at a compression rate of 25% for 22 to 24 hours. If this compression set value exceeds 30%, the dimensional change when it becomes a roller becomes so large that it is likely not to be suitable for practical use.
[0096]
  (Photoconductor contamination test)
  Example 1 to Example4, Reference Examples 1-4In Comparative Examples 1 to 8, the test was performed by the following method.
  The photosensitive member set in the cartridge (cartridge type C4127X) of Laser Jet 4050 type laser beam printer manufactured by Hewlett-Packard CompanyReference examplesThe vulcanized rubber slab sheet of the comparative example is pressed and stored for 2 weeks at 32.5 ° C. and 90% relative humidity. Thereafter, the vulcanized rubber slab sheet was removed from the photoconductor, halftone printing was performed with the printer using the photoconductor, and whether or not the printed material was stained was examined according to the following criteria.
  ○: No contamination as far as the printed material is seen
  △: Mild contamination (contamination with no problem in use that can be removed to the extent that it cannot be seen visually by imprinting within 5 sheets)
  ×: Severe contamination (contamination that reveals abnormalities by visual inspection of printed matter even when 5 or more sheets are imprinted)
  Examples5,6As for the conductive belts of Comparative Examples 9 and 10, a section of the obtained conductive belt and the photosensitive set in the laser beam printer DocuPrint 180 manufactured by Fuji Xerox Co., Ltd. and its cartridge (product code CT350035). The body was evaluated in the same manner as described above. However, the storage conditions were 45 ° C. and 80% relative humidity.
[0097]
(Measurement of hardness)
About the electroconductive roller, the hardness under the load of 500 g was measured using the type E durometer described in JIS K6253 (durometer E hardness). However, for the solid roller, the load was 1000 g.
[0098]
  As shown in Table 1 and Table 2, Examples 1 to4. Reference Examples 1-3In the conductive roller obtained from the conductive polymer composition of the above, the dissociable salt is unevenly distributed in the required one-phase first discontinuous phase, so that both have excellent electrical characteristics and problems such as migration contamination. Did not occur. In particular, the electrical resistance was less dependent on the environment, and the resistance increase during continuous energization was small. In addition, the conductive polymer composition reduced in hardness by foaming or the foaming roller using the conductive polymer composition was good because the resistance increase during energization was small.
[0099]
On the other hand, since Comparative Example 1 did not contain a dissociable salt, the volume resistivity value and the roller resistance value were too high. In Comparative Examples 2 and 3, since the dissociable salt was unevenly distributed in the continuous phase, the increase in resistance during continuous energization was not suitable. Since Comparative Examples 4 and 5 used a salt that can be dissociated in a one-phase system, the resistance increase during continuous energization was not suitable.
[0100]
Moreover, FIG. 2 mentioned above was the morphology which observed Example 2 in the phase mode in the scanning probe microscope (SPM) of an atomic force microscope (AFM) type. The morphology of Comparative Example 3 (one side: 10 μm) is shown in FIG. Comparative Example 3 is composed of one continuous phase and one discontinuous phase, and the dissociable salt is unevenly distributed in the continuous phase.
[0101]
Furthermore, FIG. 8 shows the resistance change during continuous energization of the conductive roller made of the conductive polymer composition of Example 1 and Comparative Example 2. The horizontal axis is the energization time, and the vertical axis is the roller resistance value. In Example 1 and Comparative Example 2, the roller resistance values in the initial state are almost the same, but as shown in FIG. 8, the resistance in Comparative Example 2 is significantly increased by continuous energization, whereas in Example 1, Only a slight increase.
[0102]
  As shown in Table 3 and Table 4,referenceExample4In the conductive urethane rubber composition and the conductive roller using the same, the salt that can be dissociated only in the required first non-continuous phase is unevenly distributed. Such a problem did not occur. In particular, the electrical resistance was less dependent on the environment, and the resistance increase during continuous energization was small.
[0103]
On the other hand, since Comparative Examples 6 and 7 did not contain a dissociable salt, the resistance value was high and unsuitable. Since Comparative Example 8 basically used a salt that can be dissociated in a substantially one-phase system, the increase in resistance during continuous energization was not suitable.
[0104]
  Next, examples and comparative examples of conductive polymer compositions for conductive belts are shown.
  Each compounding material described in Table 5 and Table 6 was compounded and kneaded using the tumbler and twin-screw extruder by the method described above, and then extruded by a resin extruder, and the inner diameter was 168 mm, the average thickness was 0.25 mm, Width 350mmRoll ofA conductive belt for a copying belt was produced. Tables 5 and 6 show the evaluation results and various evaluations as the belt described above.
[0105]
[Table 5]

[0106]
[Table 6]

[0107]
  (referenceExamples 5 and 6)
  A resin comprising a polyethylene oxide block nylon 12 copolymer or a polyether ester amide copolymer having a very high affinity between the cation and the anion-dissociable salt used in the present invention as a polymer constituting the discontinuous phase Using a type antistatic agent, lithium-bis (trifluoromethanesulfonyl) imide, which is a salt dissociable into a cation and an anion, was unevenly distributed. As the continuous phase, a polyester-based thermoplastic elastomer composed of a soft segment of a polyester and a hard segment of a polyester, which has a smaller affinity than the above-mentioned resin-type antistatic agent but has some affinity, was used. A master batch with the above resin-type antistatic agent was prepared and used so that the concentration of lithium-bis (trifluoromethanesulfonyl) imide was 5 wt%. In addition, since the value of R2 in the data of Comparative Example 10 and the volume specific resistance value of the composition show a reasonably low value, the thermoplastic elastomer (perprene) used in these Examples is the present invention. It can be seen that the salt used has a certain affinity.
[0108]
  (Comparative Examples 9 and 10)
  In Comparative Example 9, 20 wt% of lithium-bis (trifluoromethanesulfonyl) imide dissolved in dibutoxyethoxyethyl adipate was added to a polyester-based thermoplastic elastomer (polyether-polyester block copolymer Perprene P90BD). Using. The amount of salt was 0.5 parts by weight. Comparative example10Uses lithium-bis (trifluoromethanesulfonyl) imide for low molecular weight polyDEther compounds andMade of conductive plasticizerWithout using a medium composed of a low molecular weight polar compound, it was directly dispersed in one phase of a polyester-based thermoplastic elastomer.
[0109]
The resin-type antistatic agent 1 has a polyethylene oxide block nylon 12 copolymer as a main component. The resin-type antistatic agent 2 contains a polyether ester amide copolymer as a main component.
[0110]
  As shown in Table 5 and Table 6,referenceIn Examples 5 and 6, since the dissociable salt is unevenly distributed in the required first phase of the first discontinuous phase, both of them were excellent in electrical characteristics and did not cause problems such as migration contamination. In particular, the electrical resistance was less dependent on the environment, and the resistance increase during continuous energization was small.
[0111]
On the other hand, Comparative Example 9 uses a salt that can be dissociated in a one-phase system, and such a salt is dispersed using a medium composed of a low molecular weight polar compound. It was unsuitable. In Comparative Example 10, the increase in resistance during continuous energization was large, and the environmental dependency was slightly large.
[0112]
【The invention's effect】
  As is clear from the above description, according to the present invention, the continuous phaseAnd 2Discontinuous with a phase structure consisting of a discontinuous phase, with salts dissociable into cations and anions unevenly distributed in discontinuous phases and salts dissociable into cations and anions unevenly distributed The polymer constituting the phase has a higher affinity for the salt capable of dissociating into a cation and an anion than the polymer constituting the continuous phase. For this reason, it is possible to suppress the outflow of salt out of the system when an electric field is applied while increasing the degree of freedom of salt in the discontinuous phase and maintaining low electrical resistance. It is possible to prevent an increase in resistance during continuous electrodynamics. Furthermore, since salt is unevenly distributed in the discontinuous phase, it is not easily affected by the environment such as temperature and humidity, and due to ionic conduction, variation in electric resistance and voltage dependency are small.
[0113]
In addition, even if the electric field continues to be applied, it is suppressed that the salt migrates and appears on the surface, or the resistance value rises. Therefore, it is possible to use a salt with excellent conductivity, and the salt with excellent conductivity can be used. Excellent conductivity can be obtained even in a small amount. Therefore, problems such as bleed, bloom, photoconductor contamination and migration contamination do not occur, and the influence on other physical properties such as compression set and hardness can be reduced as much as possible.
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing the structure of a conductive polymer composition according to a first embodiment of the present invention.
FIG. 2 is a diagram showing a phase structure (morphology) of a conductive polymer forming a conductive member of Example 2 of the first embodiment.
FIG. 3 is a schematic view of a conductive roller including a conductive layer formed from the conductive polymer according to the first embodiment.
FIG. 4 of the present inventionreferenceIt is the schematic of the conductive belt formed using the conductive polymer composition of embodiment.
[Figure 5]referenceIt is a schematic diagram which shows the structure of the conductive polymer composition of embodiment.
FIG. 6 is a schematic view of an apparatus for measuring electrical characteristics of a roller such as a roller resistance value.
7 is a diagram showing a phase structure (morphology) of a conductive polymer forming a conductive member of Comparative Example 3. FIG.
8 is a graph showing a change in resistance during continuous energization of the rollers of Example 1 and Comparative Example 2. FIG.
[Explanation of symbols]
1, 1 'continuous phase
2,2 'first discontinuous phase
3 Second discontinuous phase
10 Conductive roller
11, 21 Conductive layer
12 Core
13 Conductive belt

Claims (16)

A conductive polymer composition comprising an ion conductive additive salt,
It consists of a continuous phase and two discontinuous phases of a first discontinuous phase and a second discontinuous phase, and the continuous phase and the two discontinuous phases form a sea-island structure,
The polymer constituting the continuous phase is acrylonitrile butadiene rubber (NBR), the polymer constituting the first discontinuous phase is a polyoxyalkylene copolymer or epihalohydrin polymer, and the polymer constituting the second discontinuous phase is ethylene. A propylene diene copolymer rubber (EPDM) and a polymer that constitutes the first discontinuous phase are blended with a cation and an anion dissociable salt that have the ability to reduce electrical resistance, The affinity of the polymer with the salt is such that the first discontinuous phase> the continuous phase> the second discontinuous phase, the first discontinuous phase is blended with the salt, and is unevenly distributed. Does not disperse the above-mentioned salt and suppresses the movement of the salt to the outside,
The electrical resistance value (volume resistivity) of each of the phases is defined as first discontinuous phase <continuous phase <second discontinuous phase, and the volume fraction of each phase is continuous phase> second discontinuous phase> first non-continuous. The weight ratio between the polymer constituting the continuous phase and the polymer constituting the two discontinuous phases and the polymer constituting the continuous phase is (the polymer constituting the two discontinuous phases: the polymer constituting the continuous phases) Polymer) = (20:80) to (45:55),
The conductive polymer composition is characterized in that the salt is blended at a ratio of 0.01 parts by weight or more and 20 parts by weight or less with respect to 100 parts by weight of the total polymer component, thereby forming a vulcanized rubber composition.   The acrylonitrile butadiene rubber is a low nitrile acrylonitrile butadiene rubber, the polyoxyalkylene copolymer is an ethylene oxide (EO) -propylene oxide (PO) -allyl glycidyl ether (AGE) copolymer, and the epihalohydrin polymer. The conductive polymer composition according to claim 1, wherein is an epichlorohydrin rubber made of an ethylene oxide (EO) -epichlorohydrin (EP) -allyl glycidyl ether (AGE) copolymer.   The conductive polymer composition according to claim 1 or 2, wherein sulfur and a vulcanization accelerator are blended as a vulcanizing agent, and carbon black, zinc oxide, and stearic acid are contained as a filler.   The conductive polymer composition according to any one of claims 1 to 3, wherein the first discontinuous phase is present so as to surround the second discontinuous phase.   Furthermore, the conductive polymer composition of any one of Claim 1 thru | or 4 which has mix | blended the chemical foaming agent. When the volume resistivity of the polymer constituting the first discontinuous phase is R1, and the volume resistivity of the polymer constituting the continuous phase is R2,
The conductive polymer composition according to claim 1, wherein 2.3 ≦ log ₁₀ R 2 −log ₁₀ R 1 ≦ 4.4.   The salt capable of dissociating into a cation and an anion was measured in a propylene carbonate (PC) dimethyl carbonate (DME) mixed solvent (volume fraction 1/2) at a salt concentration of 0.1 mol / l at 25 ° C. The conductive polymer composition according to any one of claims 1 to 6, wherein the electrical conductivity is 2.3 [mS / cm] or more.   The conductive polymer composition according to claim 1, wherein the salt dissociable into a cation and an anion is a salt having an anion having a fluoro group and a sulfonyl group.   The anion having a fluoro group and a sulfonyl group is an ion selected from at least one selected from the group consisting of a bis (fluoroalkylsulfonyl) imide ion, a tris (fluoroalkylsulfonyl) methide ion, and a fluoroalkylsulfonic acid ion. Item 9. The conductive polymer composition according to Item 8.   The conductive cation according to claim 8 or 9, wherein a cation of the salt having an anion having a fluoro group and a sulfonyl group is a cation of an alkali metal, a group 2A, a transition metal, or an amphoteric metal. Polymer composition.   The salt having an anion having a fluoro group and a sulfonyl group comprises an alkali metal salt of bis (trifluoromethanesulfonyl) imide, an alkali metal salt of tris (trifluoromethanesulfonyl) methide, and an alkali metal salt of trifluoromethanesulfonic acid. The conductive polymer composition according to any one of claims 8 to 10, wherein the conductive polymer composition is a salt selected from at least one of the group.   The salt capable of dissociating into a cation and an anion is blended without using a medium composed of a low molecular weight polyether compound having a number average molecular weight (Mn) of 10,000 or less or a conductive plasticizer which is a low molecular weight polar compound. The conductive polymer composition according to any one of claims 1 to 11.   The electroconductive member which consists of an electroconductive roller or an electroconductive belt formed from the electroconductive polymer composition of any one of Claims 1 thru | or 12.   A conductive roller comprising: a cylindrical metal core having conductivity; and one conductive layer formed by cylindrically forming the conductive polymer composition on the surface of the core. Item 14. The conductive member according to Item 13.   The conductive member according to claim 13, wherein the conductive polymer composition comprises a conductive belt formed into a seamless single-layer belt. A method for producing a conductive polymer composition according to any one of claims 1 to 5,
Kneading the polyoxyalkylene copolymer or epihalohydrin polymer with a salt that can dissociate into the cation and anion,
A method for producing a conductive polymer composition, wherein the obtained kneaded product is produced by kneading the acrylonitrile butadiene rubber (NBR) and the ethylene propylene diene copolymer rubber (EPDM).

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