In recent years, UV-curing printing inks have been increasingly applied in many areas of the printing industry and are recording stable growth rates. The explanation for this lies in several advantages of the UV-drying inks compared to solvent-based and water-based inks. The virtually instantaneous drying of the ink allows higher printing speeds and leads to a lower energy consumption, as a physical drying is no longer necessary. Furthermore, VOC emissions are significantly reduced compared to solvent-based inks. Ventilation and solvent-recovery systems are therefore no longer required and the risk of fire is considerably lower. In addition, UV-curing inks exhibit improved adhesion to plastics and are therefore being increasingly applied in the printing of packaging.
However, inks of this type also exhibit a number of disadvantages. The conventional binder precursors for the printing ink formulations generally consist of compounds which are esterified with acrylic acid or methacrylic acid. These have an allergenic potential which must be taken seriously as it can lead to severe contact allergies. Moreover, in contrast to physically-drying inks, there are considerably fewer ink systems in the UV-curing sector whose binders are obtained from renewable raw materials. For this reason, an alternative to (meth)acrylates from renewable raw materials is of great interest.
This is the starting point for the project. Together with our industrial partners, we are developing solvent-free polymer resins using itaconic acid and other bio-based monomers and are investigating these in printing ink formulations. The aim is the development of acrylate-free printing inks with the highest-possible proportion of renewable raw materials.
Fraunhofer Institute for Wood Research 
