Title:
MAGNETIC TONER
Document Type and Number:
WIPO Patent Application WO/2015/015791
Kind Code:
A1
Abstract:
The purpose of the present invention is to provide a toner which can attain a stable image density over the period of endurance, which is not susceptible to causing sweeping and exhibits excellent low-temperature fixability, and which is thus suitable for increase in speed and improvement in lifetime. A magnetic toner which comprises not only toner particles that each comprise both a binder resin and a magnetic body, but also inorganic nanoparticles (a) and organic-inorganic composite particles, the nanoparticles (a) and the composite particles being present on the surface of the toner particles, characterized in that (i) each organic-inorganic composite particle have a structure wherein inorganic nanoparticles (b) are embedded in a resin particle and (ii) the organic-inorganic composite particles are contained in an amount of 0.5 to 3.0mass% relative to the mass of the toner, in that the inorganic nanoparticles (a) contain at least inorganic oxide nanoparticles selected from the group consisting of silica nanoparticles, titanium oxide nanoparticles and alumina nanoparticles, and exhibit a number -average particle diameter (D1) of 5 to 25nm, with at least 85mass% of the inorganic oxide nanoparticles being silica nanoparticles, and in that when the surface coverage of the toner particles by the inorganic nanoparticles (a) is abbreviated to "coverage (A)(%)", and the surface coverage of the toner particles by the inorganic nanoparticles (a) fixed on the surface of the toner particles is abbreviated to "coverage (B) (%)", the coverage (A) is 45.0 to 70.0% and the ratio of the coverage (B) to the coverage (A), B/A ratio, is 0.50 to 0.85.
Inventors:
HOTTA YOJIRO (JP)
NISHIKAWA KOJI (JP)
TSUDA SHOHEI (JP)
SHIOZAWA MOTOHIDE (JP)
NAKA TAKESHI (JP)
TERAUCHI KAZUO (JP)
YAMAZAKI KATSUHISA (JP)
ITAKURA TAKAYUKI (JP)
NISHIKAWA KOJI (JP)
TSUDA SHOHEI (JP)
SHIOZAWA MOTOHIDE (JP)
NAKA TAKESHI (JP)
TERAUCHI KAZUO (JP)
YAMAZAKI KATSUHISA (JP)
ITAKURA TAKAYUKI (JP)
Application Number:
PCT/JP2014/003951
Publication Date:
February 05, 2015
Filing Date:
July 28, 2014
Export Citation:
Assignee:
CANON KK (JP)
International Classes:
G03G9/08; G03G9/083
Foreign References:
| JP2013134447A | 2013-07-08 | |||
| JP2013092748A | 2013-05-16 | |||
| JPH0481771A | 1992-03-16 |
Attorney, Agent or Firm:
OKABE, Yuzuru et al. (JP)
Okabe 讓 (JP)
Okabe 讓 (JP)
Download PDF: