Itaconic acid as renewable building block UV-curing printing inks

 
Acrylate and methacrylate containing polymers are the most important type of binder resins used in the field of radical UV- and EB-curing printing inks. However, these materials suffer from several drawbacks such as high allergic potential and pungent odor. In addition, despite an increasing demand for printing inks derived from renewable resources, there are to date no commercially viable routes to bio-based acrylic acid. Therefore, innovative alternatives are of great economic and environmental interest. We herein present the use of itaconic acid as a renewable and more benign alternative building block for UV-curing polymers. Itaconic acid exhibits a lower reactivity towards radical cross-linking compared to (meth)acrylic acid. However, we will show that polyesters and polyurethanes derived from this bio-based compound can be used as binder resins. These polymers exhibit a similar performance in the field of UV-curing offset inks without the drawbacks usually associated with standard systems based on acrylic acid. In addition to the use of itaconic acid as bio-based monomer, the use of a high overall content of renewable building blocks, such as 1,3-propandiol, 1,4-butandiol or alike will be discussed.