TONER AND EXTERNAL ADDITIVE FOR TONER

• Main Authors: NISHIKAWA KOJI, YOSHIBA DAISUKE, HOTTA YOJIRO, MORIBE SHUHEI, FUKUTOME KOSUKE, YAMAZAKI KATSUHISA, NOMURA SHOTARO, AKIYAMA HIROKI
• Format: Patent
• Language: English; Japanese
• Published: 21.07.2016
• Subjects: CINEMATOGRAPHY; ELECTROGRAPHY; ELECTROPHOTOGRAPHY; HOLOGRAPHY; MAGNETOGRAPHY; PHOTOGRAPHY; PHYSICS

PROBLEM TO BE SOLVED: To provide a toner excellent in developability, low-temperature fixability, and high-temperature offset resistance, and an external additive for a toner.SOLUTION: The toner includes toner particles and organic-inorganic composite fine particles on the surfaces of the toner particles. The organic-inorganic composite fine particles include resin fine particles and inorganic fine particles embedded in the surfaces of the resin fine particles; and a part of the inorganic fine particle is exposed on a surface of the organic-inorganic composite fine particles. The composite fine particles satisfy the following relationships (i) and (ii). (i) In viscoelasticity measurement of the organic-inorganic composite fine particles, when a loss elastic modulus thereof at a temperature T (°C) is represented by G''[dN/m], a change ratio d(Log(G''))/dT of a common logarithm of the loss elastic modulus shows a minimum in a temperature range from 60°C to 150°C, and the minimum is less than -0.10. (ii) A loss elastic modulus (G'') thereof at a temperature of 180°C is 1.0×10dN/mor more and 1.0×10dN/mor less.SELECTED DRAWING: Figure 1 【課題】現像性、低温定着性、耐高温オフセット性に優れたトナー及びトナー用外添剤を提供する。【解決手段】トナー粒子、及び、トナー粒子の表面に有機無機複合微粒子を有するトナーであって、有機無機複合微粒子は、樹脂微粒子と、樹脂微粒子の表面に埋め込まれた無機微粒子とを有し、有機無機複合微粒子の表面には、一部の無機微粒子が露出しており、ｉ）およびｉｉ）の関係を満たすことを特徴とする：ｉ）該有機無機複合微粒子の粘弾性測定において、温度Ｔ（℃）における損失弾性率をＧ"T［ｄＮ／ｍ2］とし、常用対数の損失弾性率の変化率ｄ（Ｌｏｇ（Ｇ"T））／ｄＴが、温度６０℃以上１５０℃以下の範囲において最小値を示し、前記最小値が−０．１０未満であり、ｉｉ）温度１８０℃における損失弾性率（Ｇ"180）が、１．０×１０4ｄＮ／ｍ2以上１．０×１０7ｄＮ／ｍ2以下である。【選択図】図１