JP4222496B2 - Rubber member for electrophotographic equipment - Google Patents

Description

【００１７】
（式中、Ｒ¹ 、Ｒ² 、Ｒ³ は、同一又は異なって、水素原子、炭素数８〜１２のアルキル基、炭素数６〜１４のアリール基を表す。）で表される化合物である。上記アリール基としては特に限定されず、例えば、フェニル基等を挙げることができる。上記アルキル基としては特に限定されず、直鎖状であっても、分岐状であっても、また環状であってもよい。
上記アルキル及び／又はアリールの亜リン酸エステルとしては、例えば、アルキル（又はアルキルフェニル）シクロヘキシルフェニルホスファイト等を挙げることができる。
【００１８】
上記加工助剤としては、上記アルカン酸（Ａ）、上記トリブチルリン酸エステル（Ｂ）、上記アルキル及び／又はアリールの亜リン酸エステル（Ｃ）が、（Ａ）：（Ｂ）：（Ｃ）＝２０〜５０：１０〜２０：３５〜６０の重量比率で配合されているものが好ましい。
（Ａ）成分の重量比率が上記範囲を超えたり、（Ｃ）成分の重量比率が上記範囲より小さいと、得られるゴム組成物の非汚染性が低下したり、均一な組成物を得ることができない場合がある。
【００１９】
本発明の電子写真装置用ゴム部材としては、例えば、帯電ローラ、帯電ブレード、現像ローラ、転写ローラ、クリーニングブレード、トナー規制ブレード等を挙げることができる。
【００２０】
上記帯電ローラとは、電子写真装置において感光体を帯電させる役割を有するものである。上記帯電ローラについて図１を参照しながら説明する。
図１は、帯電ローラの一実施形態を表す断面図である。帯電ローラは図１に示すように、芯金１１の周囲に同心円状の導電性ゴム層１２が形成されたものである。
【００２１】
上記帯電ブレードとは、電子写真装置において感光体を帯電させる役割を有するものである。上記帯電ブレードについて図２を参照しながら説明する。
図２は、帯電ブレードの一実施形態を表す正面図である。帯電ブレードは図２に示すように、板状の金属性担体２１に板状の導電性ゴム２２が接着剤層（図示せず）を介して接着されて形成されたものである。
【００２２】
【実施例】
以下に実施例を揚げて本発明を更に詳しく説明するが、本発明はこれら実施例のみに限定されるものではない。
【００２３】
配合物１〜５の評価
表１に示した組成からなる配合物１〜５を用いて、プレス加硫によって作製した加硫物シートを下記の評価方法を用いて評価した。結果を表２に示した。
更に、得られた加硫物シートを市販の有機感光体表面に貼り付け、４０℃、相対湿度９０％の環境下に１４日間放置し、その後加硫物シートを取り除いて感光体表面を目視及び金属顕微鏡にて観察し、下記の評価方法で評価した。結果を表２に示した。
【００２４】
【表１】

【００２５】
また、配合物１〜５に配合した加工助剤について、加工助剤（１）は、アルカン酸［Ｃ４〜３０］を３６重量％、トリブチルリン酸エステルを１２重量％、アルキル［Ｃ８〜１２］〔又はアルキル（Ｃ８〜１２）フェニル〕シクロヘキシルフェニルホスファイトを５２重量％含む混合物であり、加工助剤（２）は、アルカン［又はアルケン］［Ｃ１１〜２４］酸アルケニル［Ｃ６〜２４］エステルを５８重量％、トリブチルリン酸エステルを１２重量％、アルキル［Ｃ８〜１２］〔又はアルキル（Ｃ８〜１２）フェニル〕シクロヘキシルフェニルホスファイトを３０重量％含む混合物であり、加工助剤（３）はステアリン酸である。
【００２６】
評価方法
（１）ロール加工性
配合物１〜５を用いて加硫物シートを作製する際のロール加工性を以下の基準で評価した。
○：ロールから取り出すことができる。
×：ロールから取り出すことができない。
（２）体積固有抵抗（Ω−ｃｍ）
印加電圧２５０Ｖにおける抵抗値を測定した。
（３）目視観察及び金属顕微鏡観察
○：感光体表面が平滑で、くもり等が観察されない。
△：感光体表面に付着物があり、ややくもりがみられる。
×：感光体表面の付着物が顕著で、著しいくもりがみられる。
××：感光体表面に凸凹があり、くもりが顕著にみられる。
【００２７】
【表２】

【００２８】
実施例１
配合物１を用いた導電性ゴムローラ（１）、及び、配合物２を用いた導電性ゴムローラ（２）を作製した。得られた各ローラを感光体と接触させた状態で、４０℃、相対湿度９０％の環境下に１４日間放置した後、各ローラを取り除き、感光体表面を目視観察したところ感光体非汚染性は良好であった。
次に導電性ゴムローラ（１）を帯電ローラとして、導電性ゴムローラ（２）を転写ローラとして図３に示した電子写真装置に適用し、汚染試験後の有機感光体を用いた反転現像にて複写画像を形成し、下記の評価方法により評価を行った。結果を下記の表３に示した。
【００２９】
評価方法（汚染試験後の感光体を用いて形成した複写画像）
（１）地肌かぶり
得られた画像を目視観察し、以下の評価基準で評価した。
○：地肌かぶりによる画像欠陥がみられなかった。
×：感光体回転ピッチで地肌かぶりによる画像欠陥がみられた。
（２）濃度ムラ
○：濃度ムラによる画像欠陥がみられなかった。
×：感光体回転ピッチで濃度ムラによる画像欠陥がみられた。
（３）文字部の欠け
○：文字部の欠けによる画像欠陥がみられなかった。
×：感光体回転ピッチで文字部の欠けによる画像欠陥がみられた。
【００３０】
表３に示したように、得られた複写画像は、地肌かぶり、黒点汚れ、異常放電等による画像の乱れがなく、かつ、文字の中抜け、欠け、濃度ムラ等のない良好な画像であった。また、転写後の感光体表面のトナー残存もほとんどなく、良好な転写状態であることが確認された。
【００３１】
更に、有機感光体を新規なものと取り替え、導電性ゴムローラ（１）及び導電性ゴムローラ（２）を同様に図３に示した電子写真装置に適用し、反転現像にて複写画像を形成した。得られた画像について初期の画像及び５０００枚通紙後の画像を目視観察し、下記の評価方法により評価した。結果を表３に示した。
【００３２】
評価方法（新規感光体を用いて形成した複写画像）
（１）地肌かぶり
得られた画像を目視観察し、以下の評価基準で評価した。
○：地肌かぶりがみられなかった。
△：一部に地肌かぶりがみられた。
×：全体に地肌かぶりがみられた。
（２）濃度ムラ
○：濃度ムラがみられなかった。
△：一部に濃度ムラがみられた。
×：全体に濃度ムラがみられた。
（３）文字部の欠け
○：文字部の欠けがみられなかった。
△：一部に文字部の欠けがみられた。
×：全体に文字部の欠けがみられた。
【００３３】
表３に示したように、初期の画像及び５０００枚通紙後の複写画像も良好であった。
なお、本実施例で用いた電子写真装置３０は、図３に模式的に示すように構成されており、表面に光導電体層を有する感光体ドラム３８の外周面を、帯電ローラ３１を用いて一様に帯電させ、ついで、被複写体へ照射反射光に応じたレーザー光で外周を露光することにより、静電潜像を形成する。この後、この静電潜像にトナー搬送ローラ３５及び現像ローラ３６を用いてトナーを付着させ、トナー像を形成した後、転写ローラ３７により用紙に転写させて定着させることにより、複写画像を形成する。
【００３４】
実施例２
配合物１を用いた導電性ゴムブレード（１）を作製した。得られた導電性ゴムブレード（１）について、実施例１と同様にして感光体非汚染性を評価したところ感光体非汚染性は良好であった。
次に導電性ゴムブレード（１）を帯電ブレードとして、導電性ゴムローラ（２）を転写ローラとして図４に示した電子写真装置に適用した以外は、実施例１と同様にして複写画像を形成し、実施例１と同様の評価方法で評価した。結果を表３に示した。
【００３５】
表３に示したように、得られた複写画像は、地肌かぶり、黒点汚れ、異常放電等による画像の乱れがない良好な画像であった。また、転写後の感光体表面のトナー残存もほとんどなく、良好な転写状態であることが確認された。
【００３６】
更に、有機感光体を新規なものと取り替え、導電性ゴムブレード（１）及び導電性ゴムローラ（２）を同様に図４に示した電子写真装置に適用し、反転現像にて複写画像を形成した。得られた画像について初期の画像及び５０００枚通紙後の画像を目視観察し、実施例１と同様の評価方法により評価した。結果を表３に示した。
表３に示したように、初期の画像及び５０００枚通紙後の複写画像も良好であった。
【００３７】
なお、本実施例で用いた電子写真装置４０は、図４に模式的に示すように構成されており、表面に光導電体層を有する感光体ドラム４８の外周面を、帯電ブレード４１を用いて一様に帯電させ、ついで、被複写体へ照射反射光に応じたレーザー光で外周を露光することにより、静電潜像を形成する。この後、この静電潜像にトナー搬送ローラ４５及び現像ローラ４６を用いてトナーを付着させ、トナー像を形成した後、転写ローラ４７により用紙に転写させて定着させることにより、複写画像を形成する。
【００３８】
比較例１
配合物３を用いた導電性ゴムローラ（３）を作製した。得られた導電性ゴムローラ（３）について、実施例１と同様にして感光体非汚染性の評価を行ったところ感光体表面にくもり汚染が見られた。また、汚染された感光体表面を光学顕微鏡にて観察したところブルーム物と思われる物質が付着していた。
次に導電性ゴムローラ（３）を帯電ローラとして用いた以外は、実施例１と同様にして複写画像を形成し、実施例１と同様の評価方法で評価した。結果を表３に示した。
表３に示したように、得られた複写画像は、異常放電等による画像の乱れはみられなかったが、地肌かぶりがやや発生し、かつ、所々に白点状に画像の形成されない部分があり、良好な画像は得られなかった。
更に、導電性ゴムローラ（１）に代えて、導電性ゴムローラ（３）を用いた以外は、実施例１と同様して複写画像を形成し、初期及び５０００枚通紙後の画像を目視観察し、実施例１と同様の評価方法で評価した。結果を表３に示した。
表３に示したように、５０００通紙後の複写画像で、地肌かぶり、濃度ムラ及び文字部の欠け等がみられた。
【００３９】
比較例２
配合物４を用いた導電性ゴムローラ（４）を作製した。得られた導電性ゴムローラ（４）について、実施例１と同様にして感光体非汚染性の評価を行ったところ感光体表面にくもり汚染が見られた。また、汚染された感光体表面を光学顕微鏡にて観察したところブルーム物と思われる物質が付着していた。
次に導電性ゴムローラ（４）を帯電ローラとして用いた以外は、実施例１と同様にして複写画像を形成し、実施例１と同様の評価方法で評価した。結果を表３に示した。
表３に示したように、得られた複写画像は、異常放電等による画像の乱れはみられなかったが、地肌かぶりがやや発生し、かつ、所々に白点状に画像の形成されない部分があり、良好な画像は得られなかった。
更に、導電性ゴムローラ（１）に代えて、導電性ゴムローラ（４）を用いた以外は、実施例１と同様して複写画像を形成し、初期及び５０００枚通紙後の画像を目視観察し、実施例１と同様の評価方法で評価した。結果を表３に示した。
表３に示したように、５０００通紙後の複写画像で、地肌かぶり、濃度ムラ及び文字部の欠け等がみられた。
【００４０】
比較例３
配合物５を用いた導電性ゴムローラ（５）を作製した。得られた導電性ゴムローラ（５）について、実施例１と同様にして感光体非汚染性の評価を行ったところ感光体表面にくもり汚染が見られた。また、汚染された感光体表面を光学顕微鏡にて観察したところ小さな凸凹がみられた。
次に導電性ゴムローラ（５）を帯電ローラとして用いた以外は、実施例１と同様にして複写画像を形成し、実施例１と同様の評価方法で評価した。結果を表３に示した。
表３に示したように、得られた複写画像は、地肌かぶりや異常放電等による画像の乱れはみられなかったが、ローラの長手方向に一定幅で画像の形成されない部分があり、良好な画像は得られなかった。
更に、導電性ゴムローラ（１）に代えて、導電性ゴムローラ（５）を用いた以外は、実施例１と同様して複写画像を形成し、初期及び５０００枚通紙後の画像を目視観察し、実施例１と同様の評価方法で評価した。結果を表３に示した。
表３に示したように、５０００通紙後の複写画像で、地肌かぶり、濃度ムラ及び文字部の欠け等がみられた。
【００４１】
比較例４
配合物３を用いた導電性ゴムブレード（２）を作製した。得られた導電性ゴムブレード（２）について、実施例２と同様にして感光体非汚染性の評価を行ったところ感光体表面にくもり汚染が見られた。また、汚染された感光体表面を光学顕微鏡にて観察したところブルーム物と思われる物質が付着していた。
次に導電性ゴムブレード（２）を帯電ブレードとして用いた以外は、実施例２と同様にして複写画像を形成し、実施例２と同様の評価方法で評価した。結果を表３に示した。
表３に示したように、得られた複写画像は、異常放電等による画像の乱れはみられなかったが、地肌かぶりがやや発生し、かつ、所々に白点状に画像の形成されない部分があり、良好な画像は得られなかった。
更に、導電性ゴムブレード（１）に代えて、導電性ゴムブレード（２）を用いた以外は、実施例２と同様して複写画像を形成し、初期及び５０００枚通紙後の画像を目視観察し、実施例２と同様の評価方法で評価した。結果を表３に示した。表３に示したように、５０００通紙後の複写画像で、地肌かぶり、濃度ムラ及び文字部の欠け等がみられた。
【００４２】
比較例５
配合物４を用いた導電性ゴムブレード（３）を作製した。得られた導電性ゴムブレード（３）について、実施例２と同様にして感光体非汚染性の評価を行ったところ感光体表面にくもり汚染が見られた。また、汚染された感光体表面を光学顕微鏡にて観察したところブルーム物と思われる物質が付着していた。
次に導電性ゴムブレード（３）を帯電ブレードとして用いた以外は、実施例２と同様にして複写画像を形成し、実施例２と同様の評価方法で評価した。結果を表３に示した。
表３に示したように、得られた複写画像は、異常放電等による画像の乱れはみられなかったが、地肌かぶりがやや発生し、かつ、所々に白点状に画像の形成されない部分があり、良好な画像は得られなかった。
更に、導電性ゴムブレード（１）に代えて、導電性ゴムブレード（３）を用いた以外は、実施例２と同様して複写画像を形成し、初期及び５０００枚通紙後の画像を目視観察し、実施例２と同様の評価方法で評価した。結果を表３に示した。表３に示したように、５０００通紙後の複写画像で、地肌かぶり、濃度ムラ及び文字部の欠け等がみられた。
【００４３】
比較例６
配合物５を用いた導電性ゴムブレード（４）を作製した。得られた導電性ゴムブレード（４）について、実施例２と同様にして感光体非汚染性の評価を行ったところ感光体表面にくもり汚染が見られた。また、汚染された感光体表面を光学顕微鏡にて観察したところ小さな凸凹がみられた。
次に導電性ゴムブレード（４）を帯電ブレードとして用いた以外は、実施例２と同様にして複写画像を形成し、実施例２と同様の評価方法で評価した。結果を表３に示した。
表３に示したように、得られた複写画像は、地肌かぶりや異常放電等による画像の乱れはみられなかったが、ブレードの長手方向に一定幅で画像の形成されない部分があり、良好な画像は得られなかった。
更に、導電性ゴムブレード（１）に代えて、導電性ゴムブレード（４）を用いた以外は、実施例２と同様して複写画像を形成し、初期及び５０００枚通紙後の画像を目視観察し、実施例２と同様の評価方法で評価した。結果を表３に示した。表３に示したように、５０００通紙後の複写画像で、地肌かぶり、濃度ムラ及び文字部の欠け等がみられた。
【００４４】
【表３】

【００４５】
【発明の効果】
本発明の電子写真装置用ゴム部材は、上述の構成からなるため、導電性に優れるとともに非汚染性にも優れる。
【図面の簡単な説明】
【図１】本発明の電子写真装置用ゴム部材の一形態である帯電ローラを示す断面図である。
【図２】本発明の電子写真装置用ゴム部材の一形態である帯電ブレード示す正面図である。
【図３】実施例１及び比較例１〜３で用いた電子写真装置を模式的に示す断面図である。
【図４】実施例２及び比較例４〜６で用いた電子写真装置を模式的に示す断面図である。
【符号の説明】
１０、３１ 帯電ローラ
１１ 芯金
１２ 導電性ゴム層
２０、４１ 帯電ブレード
２１ 金属性担持体
２２ 導電性ゴム
３０、４０ 電子写真装置[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a rubber member for an electrophotographic apparatus used for OA equipment and the like, and particularly used for purposes such as charging, transfer, and development. Therefore, a conductive rubber composition suitable for an electrophotographic apparatus is photosensitive. The present invention relates to a rubber member for an electrophotographic apparatus applied to a portion in contact with a body.
[0002]
[Prior art]
Conductive rubber compositions are widely used as components for OA equipment and the like by utilizing their conductivity and properties as rubber. In particular, a rubber composition having a conductive performance with electrical resistance, variation stability, environmental stability, and the like is used for an electrophotographic apparatus. In recent years, with the improvement in performance of electrophotographic apparatuses, such a rubber composition has been required to have non-staining properties, low hardness, dimensional stability and the like at the same time.
[0003]
Among members using such a rubber composition, non-contamination with respect to the photosensitive member has been strongly demanded particularly in a member that directly contacts the photosensitive member in an electrophotographic apparatus.
[0004]
Of the conductivity, the electrical resistance has been conventionally controlled by kneading or dispersing a conductivity-imparting material such as carbon black, metal fine particles, and metal oxide fine particles in the rubber composition. However, it is difficult to control the dispersion, and the dispersion state changes due to the rubber flow during molding and vulcanization, resulting in variations in electrical resistance.
[0005]
As a method for solving such problems, there has been proposed a method using an epichlorohydrin copolymer as a material in which the polymer itself has conductivity. By such a method, a desired electrical resistance value can be obtained with a very small amount without using a conductivity imparting material, and variations in electrical resistance can be suppressed.
[0006]
However, in the method using a polymer as described above, the photoconductor may be contaminated depending on the vulcanization method and polymer blending, and there remains a problem that selection of the blending and vulcanization method is difficult.
[0007]
[Problems to be solved by the invention]
An object of the present invention is to provide a conductive rubber member for an electrophotographic apparatus that is excellent in conductivity and non-contaminating in view of the above situation.
[0008]
[Means for Solving the Problems]
The present invention provides a rubber member for an electrophotographic apparatus in which a portion in contact with a photoreceptor is made of a conductive rubber composition for an electrophotographic apparatus, and the electroconductive rubber composition for an electrophotographic apparatus is mainly composed of epichlorohydrin. In the rubber, containing a processing aid consisting of alkanoic acid having 4 to 30 carbon atoms , tributyl phosphate ester, and alkyl [C8-12] [or alkyl (C8-12) phenyl] cyclohexylphenyl phosphite , The rubber mainly composed of epichlorohydrin is a copolymer composed of epichlorohydrin, ethylene oxide, and allyl glycidyl ether, and the copolymerization ratio of the ethylene oxide is 5 to 40 mol% with respect to the total monomers. There is a conductive rubber member for an electrophotographic apparatus.
The present invention is described in detail below.
[0009]
In the electroconductive rubber member for electrophotographic apparatus of the present invention, the portion in contact with the photoreceptor is made of the electroconductive rubber composition for electrophotographic apparatus. The electroconductive rubber composition for an electrophotographic apparatus is made of rubber mainly composed of epichlorohydrin.
The rubber mainly composed of epichlorohydrin is a rubber mainly composed of a homopolymer of epichlorohydrin or a copolymer of epichlorohydrin and other monomers.
The other monomer is not particularly limited as long as it can be copolymerized with epichlorohydrin, and examples thereof include ethylene oxide.
The other monomers may be used alone or in combination of two or more.
[0010]
The rubber mainly composed of epichlorohydrin is preferably a copolymer composed of epichlorohydrin and ethylene oxide (hereinafter referred to as epichlorohydrin copolymer). By using the epichlorohydrin-based copolymer, it is possible to obtain a rubber having a desired electrical resistance value by adding a small amount of a conductivity-imparting material without a conductivity-imparting material. There is little variation in resistance.
The copolymerization ratio of the ethylene oxide is preferably 5 to 40 mol% with respect to all monomers. When the copolymerization ratio of the ethylene oxide is less than 5 mol%, desired conductivity may not be obtained, and when it exceeds 40 mol%, a counterpart member such as a photoreceptor may be contaminated. More preferably, it is 10-30 mol%.
[0011]
The mechanism by which ethylene oxide is involved in contamination is not clear, but if the copolymerization ratio of ethylene oxide is large, flexible oxygen resulting from the ether chain present in the molecule increases, and this causes the other member such as a photoreceptor to become a member. It is thought that the surface is altered by contact. In addition, when the ether chain increases, the amount of water contained in the polymer increases, and this plays a role of dissolving the photosensitive material contaminants (both intrinsic and external factors) and adhering them to the mating member such as the photosensitive member surface. You might also say that.
[0012]
Moreover, the composition of the said epichlorohydrin-type copolymer may be a copolymer of 3 or more types of compounds containing other compounds other than epichlorohydrin and ethylene oxide.
The other compound is not particularly limited as long as it is copolymerizable with the epichlorohydrin and the ethylene oxide, and examples thereof include allyl glycidyl ether.
[0013]
The conductive rubber composition for an electrophotographic apparatus contains a processing aid comprising an alkanoic acid, a tributyl phosphate ester, and an alkyl and / or aryl phosphite ester in the rubber mainly composed of epichlorohydrin. .
The processing aid is usually used by kneading into a rubber composition or the like as an internal mold release agent.
The processing aid has good dispersibility in the electroconductive rubber composition for an electrophotographic apparatus.
[0014]
It does not specifically limit as said alkanoic acid, For example, C4-C30 linear saturated fatty acid etc. can be mentioned. These can be used alone or in admixture of two or more.
The tributyl phosphate is normally used as a dispersion stabilizer.
[0015]
The alkyl and / or aryl phosphite is the following general formula (I):
[0016]
[Chemical 1]

[0017]
(Wherein R ¹ , R ² and R ³ are the same or different and each represents a hydrogen atom, an alkyl group having 8 to 12 carbon atoms, or an aryl group having 6 to 14 carbon atoms). . The aryl group is not particularly limited, and examples thereof include a phenyl group. The alkyl group is not particularly limited, and may be linear, branched, or cyclic.
Examples of the alkyl and / or aryl phosphite include alkyl (or alkylphenyl) cyclohexyl phenyl phosphite.
[0018]
As the processing aid, the alkanoic acid (A), the tributyl phosphate ester (B), the alkyl and / or aryl phosphite ester (C) are (A) :( B) :( C). = The thing mix | blended by the weight ratio of 20-50: 10-20: 35-60 is preferable.
If the weight ratio of the component (A) exceeds the above range, or the weight ratio of the component (C) is smaller than the above range, the non-contamination property of the resulting rubber composition may be reduced, or a uniform composition may be obtained. There are cases where it is not possible.
[0019]
Examples of the rubber member for an electrophotographic apparatus of the present invention include a charging roller, a charging blade, a developing roller, a transfer roller, a cleaning blade, and a toner regulating blade.
[0020]
The charging roller has a role of charging a photoreceptor in an electrophotographic apparatus. The charging roller will be described with reference to FIG.
FIG. 1 is a cross-sectional view illustrating an embodiment of a charging roller. As shown in FIG. 1, the charging roller is a roller in which a concentric conductive rubber layer 12 is formed around a cored bar 11.
[0021]
The charging blade has a role of charging a photoreceptor in an electrophotographic apparatus. The charging blade will be described with reference to FIG.
FIG. 2 is a front view illustrating an embodiment of the charging blade. As shown in FIG. 2, the charging blade is formed by adhering a plate-like conductive rubber 22 to a plate-like metallic carrier 21 via an adhesive layer (not shown).
[0022]
【Example】
Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to these examples.
[0023]
Evaluation of Formulations 1 to 5 Using the formulations 1 to 5 having the compositions shown in Table 1, vulcanized sheets prepared by press vulcanization were evaluated using the following evaluation methods. The results are shown in Table 2.
Further, the obtained vulcanized sheet was attached to the surface of a commercially available organic photoreceptor, left in an environment of 40 ° C. and 90% relative humidity for 14 days, after which the vulcanized sheet was removed and the surface of the photoreceptor was visually and It observed with the metal microscope and evaluated with the following evaluation method. The results are shown in Table 2.
[0024]
[Table 1]

[0025]
Further, the processing aid was blended into the formulation 1-5, processing aids (1) is 36% by weight of alkanoic acid [C4~30], 12 wt% of tributyltin Ruri phosphate esters, alkyl [C8～12 ] [Or alkyl (C8-12) phenyl] cyclohexyl phenyl phosphite, and the processing aid (2) is an alkane [or alkene] [C11-24] acid alkenyl [C6-24] ester. 58 wt%, 12 wt% of tributyltin Ruri phosphate esters, alkyl [C8~12] [or alkyl (C8～12) phenyl] is a mixture containing 30% by weight of phenyl phosphite, processing aids (3) Is stearic acid.
[0026]
Evaluation Method (1) The roll processability when producing a vulcanized sheet using the roll processability compounds 1 to 5 was evaluated according to the following criteria.
○: Can be taken out from the roll.
X: Cannot be removed from the roll.
(2) Volume resistivity (Ω-cm)
The resistance value at an applied voltage of 250 V was measured.
(3) Visual observation and metallographic microscope observation: The surface of the photoreceptor is smooth and no cloudiness is observed.
(Triangle | delta): There exists a deposit | attachment on the photoreceptor surface and a slight cloudiness is seen.
X: Deposits on the surface of the photoconductor are remarkable and significant clouding is observed.
XX: There are irregularities on the surface of the photoreceptor, and cloudiness is noticeable.
[0027]
[Table 2]

[0028]
Example 1
The conductive rubber roller (1) using the compound 1 and the conductive rubber roller (2) using the compound 2 were produced. Each roller obtained was left in contact with the photoconductor for 14 days in an environment of 40 ° C. and 90% relative humidity, and then each roller was removed and the surface of the photoconductor was visually observed. Was good.
Next, the electroconductive rubber roller (1) is used as a charging roller, and the electroconductive rubber roller (2) is used as a transfer roller, which is applied to the electrophotographic apparatus shown in FIG. 3 and copied by reversal development using an organic photoreceptor after a contamination test. Images were formed and evaluated by the following evaluation methods. The results are shown in Table 3 below.
[0029]
Evaluation method (copy image formed using photoconductor after contamination test)
(1) The image obtained from the background cover was visually observed and evaluated according to the following evaluation criteria.
○: Image defects due to background fogging were not observed.
X: Image defects due to background fogging were observed at the photoreceptor rotation pitch.
(2) Density unevenness O: No image defect due to density unevenness was observed.
X: Image defects due to density unevenness were observed at the photosensitive member rotation pitch.
(3) Missing character portion ○: Image defect due to missing character portion was not observed.
X: Image defects due to missing characters were observed at the photoreceptor rotation pitch.
[0030]
As shown in Table 3, the obtained copied image is a good image with no background distortion, black spot stains, abnormal discharge due to abnormal discharge, etc., and no missing characters, missing characters, uneven density, etc. It was. Further, there was almost no toner remaining on the surface of the photoconductor after the transfer, and it was confirmed that the transfer state was good.
[0031]
Further, the organic photoreceptor was replaced with a new one, and the conductive rubber roller (1) and the conductive rubber roller (2) were similarly applied to the electrophotographic apparatus shown in FIG. 3, and a copy image was formed by reversal development. Regarding the obtained image, the initial image and the image after 5000 sheets were visually observed and evaluated by the following evaluation methods. The results are shown in Table 3.
[0032]
Evaluation method (copy image formed using a new photoconductor)
(1) The image obtained from the background cover was visually observed and evaluated according to the following evaluation criteria.
○: Scratch was not seen.
(Triangle | delta): The surface fogging was seen in part.
X: The whole body was fogged.
(2) Density unevenness ◯: Density unevenness was not observed.
Δ: Density unevenness was partially observed.
X: Density unevenness was observed throughout.
(3) Missing character portion ○: Missing character portion was not observed.
Δ: Some missing characters were observed.
X: The lack of a character part was seen in the whole.
[0033]
As shown in Table 3, the initial image and the copied image after passing 5000 sheets were also good.
The electrophotographic apparatus 30 used in this example is configured as schematically shown in FIG. 3, and the charging roller 31 is used for the outer peripheral surface of the photosensitive drum 38 having a photoconductor layer on the surface. Then, an electrostatic latent image is formed by exposing the outer periphery with a laser beam corresponding to the reflected reflected light. Thereafter, toner is attached to the electrostatic latent image using the toner conveying roller 35 and the developing roller 36 to form a toner image, which is then transferred onto a sheet by a transfer roller 37 and fixed to form a copy image. To do.
[0034]
Example 2
A conductive rubber blade (1) using Formulation 1 was prepared. The obtained conductive rubber blade (1) was evaluated for photoreceptor non-contamination in the same manner as in Example 1. The photoreceptor non-contamination was good.
Next, a copy image was formed in the same manner as in Example 1 except that the conductive rubber blade (1) was used as a charging blade and the conductive rubber roller (2) was used as a transfer roller in the electrophotographic apparatus shown in FIG. The evaluation method was the same as in Example 1. The results are shown in Table 3.
[0035]
As shown in Table 3, the obtained copied image was a good image free from image disturbance due to background fogging, black spot stains, abnormal discharge, and the like. Further, there was almost no toner remaining on the surface of the photoconductor after the transfer, and it was confirmed that the transfer state was good.
[0036]
Further, the organic photoreceptor was replaced with a new one, and the conductive rubber blade (1) and the conductive rubber roller (2) were similarly applied to the electrophotographic apparatus shown in FIG. 4 to form a copy image by reversal development. . Regarding the obtained image, the initial image and the image after 5000 sheets were visually observed and evaluated by the same evaluation method as in Example 1. The results are shown in Table 3.
As shown in Table 3, the initial image and the copied image after passing 5000 sheets were also good.
[0037]
The electrophotographic apparatus 40 used in this example is configured as schematically shown in FIG. 4, and the charging blade 41 is used as the outer peripheral surface of the photosensitive drum 48 having a photoconductor layer on the surface. Then, an electrostatic latent image is formed by exposing the outer periphery with a laser beam corresponding to the reflected reflected light. Thereafter, toner is attached to the electrostatic latent image using the toner conveying roller 45 and the developing roller 46 to form a toner image, which is then transferred onto a sheet by a transfer roller 47 and fixed to form a copy image. To do.
[0038]
Comparative Example 1
A conductive rubber roller (3) using Formulation 3 was produced. The obtained conductive rubber roller (3) was evaluated for non-contamination of the photoreceptor in the same manner as in Example 1. As a result, clouding contamination was observed on the surface of the photoreceptor. Further, when the contaminated surface of the photoreceptor was observed with an optical microscope, a substance that seemed to be a bloom was adhered.
Next, a copy image was formed in the same manner as in Example 1 except that the conductive rubber roller (3) was used as a charging roller, and evaluated by the same evaluation method as in Example 1. The results are shown in Table 3.
As shown in Table 3, the obtained copied image showed no image disturbance due to abnormal discharge or the like, but there was some background fogging, and there were portions where the image was not formed in white spots in some places. There was no good image.
Further, a copy image was formed in the same manner as in Example 1 except that the conductive rubber roller (3) was used instead of the conductive rubber roller (1), and the initial image and the image after 5000 sheets were visually observed. The evaluation method was the same as in Example 1. The results are shown in Table 3.
As shown in Table 3, background copy, density unevenness, lack of character portions, and the like were observed in a copy image after 5000 paper passes.
[0039]
Comparative Example 2
A conductive rubber roller (4) using the formulation 4 was produced. The obtained conductive rubber roller (4) was evaluated for non-contamination of the photoconductor in the same manner as in Example 1. As a result, cloudy contamination was observed on the surface of the photoconductor. Further, when the contaminated surface of the photoreceptor was observed with an optical microscope, a substance that seemed to be a bloom was adhered.
Next, a copy image was formed in the same manner as in Example 1 except that the conductive rubber roller (4) was used as a charging roller, and evaluated by the same evaluation method as in Example 1. The results are shown in Table 3.
As shown in Table 3, the obtained copied image showed no image disturbance due to abnormal discharge or the like, but there was some background fogging, and there were portions where the image was not formed in white spots in some places. There was no good image.
Further, a copy image was formed in the same manner as in Example 1 except that the conductive rubber roller (4) was used instead of the conductive rubber roller (1), and the initial image and the image after 5000 sheets were visually observed. The evaluation method was the same as in Example 1. The results are shown in Table 3.
As shown in Table 3, background copy, density unevenness, lack of character portions, and the like were observed in a copy image after 5000 paper passes.
[0040]
Comparative Example 3
A conductive rubber roller (5) using Formulation 5 was produced. The obtained conductive rubber roller (5) was evaluated for non-contamination of the photoreceptor in the same manner as in Example 1. As a result, clouding contamination was observed on the surface of the photoreceptor. Further, when the contaminated photoreceptor surface was observed with an optical microscope, small irregularities were observed.
Next, a copy image was formed in the same manner as in Example 1 except that the conductive rubber roller (5) was used as a charging roller, and evaluated by the same evaluation method as in Example 1. The results are shown in Table 3.
As shown in Table 3, the obtained copied image did not show image disturbance due to background fogging or abnormal discharge, but there was a portion in which the image was not formed with a constant width in the longitudinal direction of the roller. No image was obtained.
Further, a copy image was formed in the same manner as in Example 1 except that the conductive rubber roller (5) was used instead of the conductive rubber roller (1), and the initial image and the image after 5000 sheets were visually observed. The evaluation method was the same as in Example 1. The results are shown in Table 3.
As shown in Table 3, background copy, density unevenness, lack of character portions, and the like were observed in a copy image after 5000 paper passes.
[0041]
Comparative Example 4
A conductive rubber blade (2) using Formulation 3 was prepared. The obtained conductive rubber blade (2) was evaluated for non-contamination of the photoreceptor in the same manner as in Example 2. As a result, clouding contamination was observed on the surface of the photoreceptor. Further, when the contaminated surface of the photoreceptor was observed with an optical microscope, a substance that seemed to be a bloom was adhered.
Next, a copy image was formed in the same manner as in Example 2 except that the conductive rubber blade (2) was used as a charging blade, and evaluated by the same evaluation method as in Example 2. The results are shown in Table 3.
As shown in Table 3, the obtained copied image showed no image disturbance due to abnormal discharge or the like, but there was some background fogging, and there were portions where the image was not formed in white spots in some places. There was no good image.
Further, a copy image was formed in the same manner as in Example 2 except that the conductive rubber blade (2) was used instead of the conductive rubber blade (1), and the initial image and the image after 5000 sheets were visually observed. Observed and evaluated by the same evaluation method as in Example 2. The results are shown in Table 3. As shown in Table 3, background copy, density unevenness, lack of character portions, and the like were observed in a copy image after 5000 paper passes.
[0042]
Comparative Example 5
A conductive rubber blade (3) using Formulation 4 was prepared. The obtained conductive rubber blade (3) was evaluated for non-contamination of the photoreceptor in the same manner as in Example 2. As a result, cloudy contamination was observed on the surface of the photoreceptor. Further, when the contaminated surface of the photoreceptor was observed with an optical microscope, a substance that seemed to be a bloom was adhered.
Next, a copy image was formed in the same manner as in Example 2 except that the conductive rubber blade (3) was used as a charging blade, and evaluated by the same evaluation method as in Example 2. The results are shown in Table 3.
As shown in Table 3, the obtained copied image showed no image disturbance due to abnormal discharge or the like, but there was some background fogging, and there were portions where the image was not formed in white spots in some places. There was no good image.
Further, a copy image was formed in the same manner as in Example 2 except that the conductive rubber blade (3) was used in place of the conductive rubber blade (1), and the initial image and the image after 5000 sheets were visually observed. Observed and evaluated by the same evaluation method as in Example 2. The results are shown in Table 3. As shown in Table 3, background copy, density unevenness, lack of character portions, and the like were observed in a copy image after 5000 paper passes.
[0043]
Comparative Example 6
A conductive rubber blade (4) using Formulation 5 was produced. The obtained conductive rubber blade (4) was evaluated for non-contamination of the photoconductor in the same manner as in Example 2. As a result, clouding contamination was observed on the surface of the photoconductor. Further, when the contaminated photoreceptor surface was observed with an optical microscope, small irregularities were observed.
Next, a copy image was formed in the same manner as in Example 2 except that the conductive rubber blade (4) was used as a charging blade, and evaluated by the same evaluation method as in Example 2. The results are shown in Table 3.
As shown in Table 3, the obtained copied image did not show image disturbance due to background fogging or abnormal discharge, but there was a portion where no image was formed with a constant width in the longitudinal direction of the blade. No image was obtained.
Further, a copy image was formed in the same manner as in Example 2 except that the conductive rubber blade (4) was used in place of the conductive rubber blade (1), and the initial image and the image after 5000 sheets were visually observed. Observed and evaluated by the same evaluation method as in Example 2. The results are shown in Table 3. As shown in Table 3, background copy, density unevenness, lack of character portions, and the like were observed in a copy image after 5000 paper passes.
[0044]
[Table 3]

[0045]
【The invention's effect】
Since the rubber member for an electrophotographic apparatus of the present invention has the above-described configuration, it has excellent conductivity and non-staining properties.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a charging roller which is an embodiment of a rubber member for an electrophotographic apparatus of the present invention.
FIG. 2 is a front view showing a charging blade which is an embodiment of a rubber member for an electrophotographic apparatus of the present invention.
3 is a cross-sectional view schematically showing the electrophotographic apparatus used in Example 1 and Comparative Examples 1 to 3. FIG.
4 is a cross-sectional view schematically showing an electrophotographic apparatus used in Example 2 and Comparative Examples 4 to 6. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10, 31 Charging roller 11 Core metal 12 Conductive rubber layers 20, 41 Charging blade 21 Metal carrier 22 Conductive rubber 30, 40 Electrophotographic apparatus

Claims (1)

The portion in contact with the photoreceptor is a rubber member for an electrophotographic apparatus made of a conductive rubber composition for an electrophotographic apparatus,
The conductive rubber composition for an electrophotographic apparatus includes an alkanoic acid having 4 to 30 carbon atoms , a tributyl phosphate ester, and an alkyl [C8-12] [or alkyl (C8- 12) containing a processing aid consisting of phenyl] cyclohexyl phenyl phosphite ,
The rubber mainly composed of epichlorohydrin is a copolymer composed of epichlorohydrin, ethylene oxide, and allyl glycidyl ether, and the copolymerization ratio of the ethylene oxide is 5 to 40 mol% with respect to the total monomers. An electroconductive rubber member for an electrophotographic apparatus, wherein the electroconductive rubber member is provided.

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