TONER

• Main Authors: HOTTA YOJIRO, FUJIMOTO MASAMI, TERAUCHI KAZUO, TSUDA SHOHEI, SHIOZAWA MOTOHIDE, NAKA TAKESHI
• Format: Patent
• Language: English; Japanese
• Published: 29.06.2017
• Subjects: CINEMATOGRAPHY; ELECTROGRAPHY; ELECTROPHOTOGRAPHY; HOLOGRAPHY; MAGNETOGRAPHY; PHOTOGRAPHY; PHYSICS

PROBLEM TO BE SOLVED: To provide a spherical toner that provide good cleanability even in an electrophotographic system where the long life is needed, has good thin line reproducibility, and can reduce contamination on a charging member.SOLUTION: There is provided a toner including toner particles and fine particles on a surface of each of the toner particles, where (i) the average circularity of the toner particles is 0.960 or more; (ii) wall surface friction angle θ of the toner is 10° or more and 15° or less; (iii) the total energy Et is 300 mJ or more and 600 mJ or less; (iv) the fine particles contain a fine particles A including primary particles having a number average particle diameter (D1) of 200 nm or more and 500 nm or less, and the isolation ratio of the fine particles A from the toner particles is 10 mass% or more and 50 mass% or less. θ and Et are defined in the specification.SELECTED DRAWING: None 【課題】長寿命が求められる電子写真システムにおいても、良好なクリーニング性をもたらし、細線再現性が良好で、且つ帯電部材の汚染を軽減することの可能な球形トナーを提供する。【解決手段】トナー粒子及び該トナー粒子の表面に微粒子を有するトナーであって、ｉ）トナー粒子の平均円形度が０．９６０以上であり、ｉｉ）トナーの壁面摩擦角θが１０°以上１５°以下であり、ｉｉｉ）トータルエナジーＥｔが３００ｍＪ以上６００ｍＪ以下であり、ｉｖ）該微粒子は、一次粒子の個数平均粒径（Ｄ１）が２００ｎｍ以上５００ｎｍ以下である微粒子Ａを含有し、該微粒子Ａは、トナー粒子からの遊離率が１０質量％以上５０質量％以下である。θおよびＥｔは明細書に定義される。【選択図】なし