To improve blocking resistance, melt flowability, low temp. fixability and electrostatic charge characteristics even at high humidity by using a specified polyester resin having a specified content of a polyhydric alcohol.
This polyester resin contains 50-100 mol.% aliphatic diol and 10-60 mol.% arom. diol of the formula, based on the amt. of all the acid components. In the formula, R is ≥3C alkylene and (x) and (y) are numbers satisfying 2.0≤x+y≤7.0. The content of a polyhydric alcohol in the polyester resin is 3-15 mol.% in the case of a trihydric alcohol and 0.5-2.5 mol.% in the base of a tetrahydric alcohol, based on the amt. of all the acid components. The polyester resin has 120-160°C softening temp., 0.5-10 mgKOH/g acid value and 55-70°C glass transition temp. The toner for developing an electrostatic charge image contains the polyester resin as a binder.
ITO KOICHI
SHIMIZU KOJI
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