TONER FOR ELECTROPHOTOGRAPHY, AND IMAGE FORMING METHOD, IMAGE FORMING APPARATUS AND PROCESS CARTRIDGE USING THE TONER

摘要

A toner is provided. The toner includes a crystalline polyester resin (A); and a non-crystalline resin (B). The toner has a viscoelastic property such that the loss tangent (tan δ) defined as a ratio (G″/G′) of loss elastic modulus (G″) to storage elastic modulus (G′) has at least an inflection point or a local maximal point at a temperature α in a temperature range of from 65° C. to 80° C. while having a local maximal point at a temperature β in a temperature range of from 75° C. to 90° C., wherein the loss tangent at the temperature α is from 1.2 to 2.0, and the loss tangent at the temperature β is from 1.0 to 2.5, wherein the temperature α is lower than the temperature β.

主权项

1. A toner comprising:
a crystalline polyester resin (A); and a non-crystalline resin (B), wherein the toner includes a tetrahydrofuran-soluble component and a chloroform-insoluble component, and wherein the toner has an infrared absorption property such that when the toner is preserved for 12 hours at 45° C. and then subjected to an attenuated total reflection Fourier transform infrared spectroscopic analysis (ATR-FTIR), a ratio (C/R) of a height (C) of a peak specific to the crystalline polyester resin (A) to a height (R) of another peak specific to the non-crystalline polyester resin (B) is from 0.03 to 0.55; a molecular weight distribution property such that the tetrahydrofuran-soluble component of the toner has a molecular weight distribution curve obtained by gel permeation chromatography (GPC) such that a main peak is present in a range of from 1,000 to 10,000, and a half width of the main peak is not greater than 20,000; and a viscoelastic property such that a curve of loss tangent (tan δ) defined as a ratio (G″/G′) of loss elastic modulus (G″) to storage elastic modulus (G′) has at least an inflection point or a local maximal point at a temperature α in a temperature range of from 65° C. to 80° C. while having a local maximal point at a temperature β in a temperature range of from 75° C. to 90° C., wherein a value of the loss tangent at the temperature α is from 1.2 to 2.0, and a value of the loss tangent at the temperature β is from 1.0 to 2.5, wherein the temperature α is lower than the temperature β.