Patent ID: 9182693
Filing Date: 2015-11-10
Classification: G03G

Abstract:
1. A toner to develop an electrostatic charge image, the toner comprising at least a binder resin, a colorant, and a releasing agent, wherein the binder resin comprises about 80 to about 98 mass % of an amorphous polyester resin and about 2 to about 20 mass % of a crystalline polyester resin, wherein the toner has a core-shell structure comprising a core layer and a shell layer, wherein the core layer comprises an amorphous polyester resin and a crystalline polyester resin as a binder resin and the shell layer comprises only an amorphous polyester resin as a binder resin, wherein a weight average molecular weight of the toner measured by using a gel permeation chromatography (GPC) method on a tetrahydrofuran (THF) soluble fraction is in a range of about 35,000 to about 60,000 g/mol, wherein a molecular weight distribution curve of the toner obtained by using the GPC method on the THF soluble fraction has at least one peak in a molecular weight range of greater than or equal to 100 and less than 1,000 g/mol, a peak in a molecular weight range of 1,000 to 5,000 g/mol, and a main peak in a molecular weight range of 5,000 to 20,000 g/mol, and wherein in the molecular weight distribution curve of the toner obtained by using the GPC method on the THF soluble fraction, a peak area corresponding to a molecular weight of 1,000 g/mol or less provides for about 4% to about 8% of a total area of the molecular weight distribution curve.