Bio-based polyester itaconates as binder resins for UV-curing offset printing inks

摘要

UV-curing inks have several economic and environmental advantages compared with standard printing inks, such as high printing velocities, low VOC emissions and good adhesion to nonabsorbing substrates. However, there are also some drawbacks, such as residual monomers, pungent odor and allergic potential of monomers and prepolymers derived from acrylic acid. In addition, only few examples of UV-curing inks derived from renewable resources are known. Herein, acrylate-free UV-curing polyester itaconates with a renewable content up to 100% and their application as binder resins in UV-curing offset ink formulations are presented. In order to obtain a high renewable content in the polyester resins, Zn(OAc)(2) had to be used as polycondensation catalyst, as standard Bronsted acid catalyst led to undesired side reactions. The resins obtained with this synthetic protocol were tested on their reactivity, which was slightly lower than a commercial polyester acrylate. Printing inks formulated from these polyester itaconates showed interesting properties despite the fact that no acrylic acid was incorporated in the resins.