Advantage of Polyester ResinsIn past years, polyester resins have been mainly used for color toners. However in recent years, polyester resins have been finding more and more widespread applications in the production of all types of toners. The main advantage of polyester resin is the superior fusing performance at lower fixing temperature compared to with the conventional styrene-acrylate resins. This advantage is due in part to the inherent molecular structure of the polyester resins; in particular the roleplayed by functionalities such as carboxylic acid groups, hydroxyl groups, and ester bonds. This report will elaborate on the reasons why polyesters enjoy an advantage in lower temperature fusing.Improvement of Disadvantage of Polyester ResinsOn the other hand, polyester resins have some disadvantages such as an ambient dependency of the tribo charge, slower mill rates due to resin toughness, and increased cost due to higher specific gravity. However these disadvantages have been overcome in several ways, such as through the use of hybrid resins, (co-polymers with styrene acrylate), polymer blends, careful selection of the monomer, and so on. And also these problems can be improved by the modification of the other toner components, such as surface additives, and charge control agents.This paper will elaborate on some of these approaches.