CONDUCTIVE ROLLER FOR ELECTROPHOTOGRAPHY

• Main Author: ICHIGE HIDETOSHI
• Format: Patent
• Language: English; Japanese
• Published: 08.11.2022
• Subjects: BEARINGS; BLASTING; CHEMISTRY; CINEMATOGRAPHY; COMPOSITIONS BASED THEREON; COMPOSITIONS OF MACROMOLECULAR COMPOUNDS; ELECTROGRAPHY; ELECTROPHOTOGRAPHY; ELEMENTS OR CRANKSHAFT MECHANISMS; ENGINEERING ELEMENTS AND UNITS; FLEXIBLE SHAFTS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVEFUNCTIONING OF MACHINES OR INSTALLATIONS; HEATING; HOLOGRAPHY; LIGHTING; MAGNETOGRAPHY; MECHANICAL ENGINEERING; METALLURGY; ORGANIC MACROMOLECULAR COMPOUNDS; PHOTOGRAPHY; PHYSICS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; SHAFTS; THEIR PREPARATION OR CHEMICAL WORKING-UP; THERMAL INSULATION IN GENERAL; USE OF INORGANIC OR NON-MACROMOLECULAR ORGANIC SUBSTANCES ASCOMPOUNDING INGREDIENTS; WEAPONS

To provide a conductive roller that has weatherability to withstand exposure to ozone in a use environment inside an image forming apparatus, prevents a deterioration in energization and an increase in hardness of a conductive elastic layer due to continuous use, and can prevent contamination of a member in contact with the conductive elastic layer during storage.SOLUTION: A conductive roller for electrophotography 1 has a conductive shaft core body 2 and a conductive elastic layer 3. The conductive elastic layer 3 is formed by vulcanizing a conductive rubber composition containing a base polymer, sulfur, organic peroxide, first carbon black, and second carbon black. The base polymer contains styrene-butadiene rubber and ethylene-propylene-diene rubber at a predetermined ratio. The first carbon black has a primary particle diameter of 18-30 nm and a DBP absorption amount of 50-130 ml/100 g, and the second carbon black has a primary particle diameter of 80-125 nm and a DBP absorption amount of 10-47 ml/100 g.SELECTED DRAWING: Figure 1 【課題】画像形成装置内の使用環境等におけるオゾン暴露に耐える耐候性を有し、連続使用による導電性弾性層の通電劣化や硬度の上昇が抑制され、かつ、保管時に導電性弾性層に接触する部材への汚染を抑制できる導電性ローラを提供する。【解決手段】電子写真用導電性ローラ１は、導電性軸芯体２と導電性弾性層３とを有し、前記導電性弾性層３が、ベースポリマー、硫黄、有機過酸化物、第１カーボンブラックおよび第２カーボンブラックを含有する導電性ゴム組成物を加硫することで形成されたものであり、前記ベースポリマーがスチレンブタジエンゴムとエチレンプロピレンジエンゴムとを所定の比率で含有し、前記第１カーボンブラックの一次粒子径が１８～３０ｎｍ、ＤＢＰ吸収量が５０～１３０ｍｌ／１００ｇであり、第２カーボンブラックの一次粒子径が８０～１２５ｎｍ、ＤＢＰ吸収量が１０～４７ｍｌ／１００ｇであることを特徴とする。【選択図】図１