Patent ID: 7955771
Filing Date: 2011-06-07
Classification: G03G

Abstract:
1. A melt-mixed toner for electrostatic image development, comprising an organic pigment and a binding resin produced by melt-mixing, and satisfying the formula (I): wherein A represents an entire area of a graph (x-axis: wavelength of a visible radiation region (380 to 780 nm), y-axis: transmittance (0 to 100%)) showing a spectral transmittance curve of a supernatant fluid, the supernatant fluid being obtained by subjecting the toner to an extraction process, the extraction process using a supercritical fluid; R represents an area determined by a Rectangular method on the basis of a spectral transmittance curve in the graph; and C represents a concentration (wt %) of the organic pigment in the toner, the organic pigment having a dispersion particle diameter of 1/10 to ½ of a maximum absorption wavelength of the organic pigment, and the organic pigment having a dispersion particle diameter of 1/10 to 4/7 of a maximum absorption wavelength of the organic pigment when the organic pigment is a yellow pigment, and the toner having a haze of 16 or less; wherein (A) the concentration of the organic pigment C in the toner is 8 wt % to 20 wt %, (B) a magenta pigment and a cyan pigment in the toner each have a dispersion particle diameter of 1/10 to ½ of a maximum absorption wavelength, (C) the formula (I) describes a level of impurities in the organic pigments which does not degrade chroma or transparency, (D) the particle diameter of magenta pigment, cyan pigment and yellow pigment, when present, all pigments of said toner to exhibit favorable transparency, and (E) the haze of said toner is sufficiently limited such that said toner exhibits favorable transparency.