Toner for developing electrostatic image

A toner for developing an electrostatic image, comprising:

• a binder resin, a metal-containing compound reactive with said binder resin and a colorant, wherein the binder resin contains (a) a first component of a low molecular weight in amounts of less than 80 wt. % detectable as an extract in 6 hours of extraction, and (b) a second component in amounts of at least 20 wt. % detectable as an extraction residue after 6 hours of extraction , said second component including (c) a third component of a tetrahydrofuran-non-extractable matter in amounts of below 20 wt. % detectable as an extraction residue after 72 hours of extraction;
• each said extraction being a Soxhlet extraction with tetrahydrofuran, wherein the toner shows a dynamic modulus and a loss modulus, respectively at 200.degree. C. and 0.1 Hz, which are substantially unchanging with time.