Patent ID: 7943281
Filing Date: 2011-05-17
Classification: G03G

Abstract:
1. A black toner comprising at least a binder resin and an iron-titanium composite oxide; said iron-titanium composite oxide being a colorant and contained in an amount of from 20 parts by mass to 70 parts by mass based on 100 parts by mass of the binder resin; said iron-titanium composite oxide consisting essentially of a mixture of a FeTiO said iron-titanium composite oxide having a saturation magnetization of 3.8 μm said black toner having a weight average particle diameter D4 of from 3.0 to 9.0 um and a saturation magnetization of 2.0 μm said black toner having, in X-ray diffraction thereof, a maximum peak at 2θ=from 32.5 to 33.1 degrees; the maximum peak having a half width of 0.20 degree or less; and said black toner having an iron-titanium composite oxide having a maximum frequency of linearity within the range where the linearity is smaller than 2.4 and an iron-titanium composite oxide having a linearity of 3.0 or more in a proportion of less than 30% by number, in regard to the number frequency distribution of the linearity of the iron-titanium composite oxide, expressed by the following expression, in a sectional photograph of the toner: Linearity={(absolute maximum length of iron-titanium composite oxide)