Patent attributes
A process for preparing a toner including the steps of (I) melt-kneading a raw material mixture containing a resin binder, a wax, and a colorant with an open-roller type kneader; (II) cooling the melt-kneaded mixture obtained in the step (I) and pulverizing the cooled mixture; and (III) classifying the pulverized product obtained in the step (II) to give a toner, wherein the wax is contained in the toner in an amount of from 2 to 15% by weight, and has a number-average particle size in the toner of 1 μm or less, wherein the toner has a volume-median particle size (D50) of from 3.5 to 7 μm, and a standard deviation in volume base particle size distribution of ¼ of D50 or less, and contains 5% by volume or less of particles having particle sizes of (1.4×D50) μm or more, and 5% by number or less of particles having particle sizes of 3 μm or less. The toner can be used, for instance, for the development of a latent image formed in electrophotography, electrostatic recording method, electrostatic printing method or the like.
