Patent ID: 7638251

Claim:
A toner comprising at least a binder resin and a colorant, wherein, in a master curve of the toner at a reference temperature of 150° C., a difference G′ (1000)−G′ (0.1) between a storage modulus G′ (0.1) at a frequency of 0.1 Hz and a storage modulus G′ (1000) at a frequency of 1000 Hz is within a range of from 0 to 2.5×10 5 Pa, where an activation energy Ea determined from a shift factor aT in the state above is within a range of from 50 to 130 kJ/mol, wherein the binder resin in the toner has a low crosslinking density and contains a THF-insoluble matter A that is not extracted by a Soxhlet extraction with tetrahydrofuran (THF) for 16 hours, and the THF-insoluble matter A contains a TOL-insoluble matter B that is not extracted by a Soxhlet extraction with toluene (TOL) for 16 hours, and the THF-insoluble matter A and the TOL-insoluble matter B satisfy a relation 0.1≦B/A≦0.6.