HYPER-BRANCHED POLYMER OF AN ESTER TYPE, AS WELL AS A TONER FOR ELECTROPHOTOGRAPHY AND A PIGMENT MASTER BATCH USING THE SAME

摘要

[Problems] To produce a hyper-branched polymer having excellent resin strength, a good anti-blocking property and less environmental dependence. [Means for Solving Problems] Disclosed is a hyper-branched ester polymer which is modified with a rosin. Preferably, the polymer has a number average molecular weight of 1,000 to 60,000, a hydroxyl value of 2 to 450 mg KOH/g, an acid value of 1 to 70 mg KOH/g, a glass transition temperature of 30° C. or higher.