Sk Chemicals Co., Ltd.

Jae-Kyoung Roh

Tae-Woong Lee

Young-Man Yoo

Kye-Yune Lee

A toner for an electrophotographic image forming process or an electrostatic printing process, and a polyester resin for the toner are disclosed. The polyester resin comprises: acid components including 70 to 96 mol % of aromatic dibasic acid component, 3 to 20 mol % of cycloaliphatic dibasic acid component, and 1 to 10 mol % of trivalent or higher acid component; alcohol components including 10 to 50 mol % of cycloaliphatic diol component, 2 to 20 mol % of trihydric or higher alcohol component, and 30 to 88 mol % of aliphatic diol component; and a heat stabilizer.

Polyester resin and toner including the same

A polyester resin which includes acid components having aromatic dibasic acid component and trivalent or higher acid component; alcohol components including aliphatic, aromatic or cycloaliphatic diol component, and trihydric or higher alcohol component; polyolefin polyol having 1,800 to 2,500 number average molecular weight and hydroxyl value of 40 to 55 KOHmg/g; and wax having melting point of 80 to 110, wherein the amount of the polyolefin polyol is 0.1 to 2 weight % and the amount of the wax is 0.5 to 15 weight % with respect to the total polyester resin. Also disclosed is a method for preparing polyester resin by (a) carrying out an esterification reaction or an ester exchange reaction with the acid components, the alcohol components, and the polyolefin polyol; and (b) carrying out a polycondensation reaction for reaction product of the esterification or ester exchange reaction in the presence of the wax.

Growing community of inventors

Gyeonggi-do, South Korea

Jae-Kyoung Roh