Eco-friendliness of inkjet inks and a novel solution to increase it

Eco-friendly inks have appeared also to digital printing area during last ten years, although every ink manufacture has slightly different determination for "eco-ink". One way to increase the eco-friendliness is to use bio-based ingredients instead of petroleum-based materials. The term "bio-based" describes a product that utilizes biological products, or renewable domestic agricultural or forestry materials. At the moment the bio-based materials of inkjet inks are mainly originating from soybean or other sources that are suitable also for food, which makes their use arguable. The water soluble wood hemicelluloses could offer a truly sustainable option for binder in water-based inks. Lately the paper industry has intensively started to study how to exploit the wood maximally in pulp making process and the isolation of hemicelluloses from pulp making waste waters has been recognized to be one of the promising ways to utilize the side streams. Due to newness of eco-friendly inks, the terminology is still very fragmented. In this paper we consider the term eco-friendly ink and how it is used nowadays. The isolation methods of hemicelluloses and their properties and suitability for inkjet inks are discussed including some test results of hemicellulose-based ink.