Conductive Inks based on Reduced Graphene Oxide

The GraphInk project aims to develop sustainable, cost-effective, and scalable electrically conductive inks based on reduced graphene oxide (rGO), enabling the industrialization and the commercialization of new highly conductive inks for the printed electronic market. The rGO-based inks developed during the Graphink project will show increased electrical conductivity and stability compared to other benchmark carbon-based inks, while being more cost-effective and less toxic than conventional metal-based inks. The project originates from a recent breakthrough in LayerOne which allowed to develop new grades of rGO showing electrical conductivity two orders of magnitude higher than standard rGO grades. During the GraphInk project, LayerOne will work further on the development and the manufacturing of rGO grades at industrial scale, while SINTEF AS will engage as R&D supplier and use the rGO grades from LayerOne as starting materials to develop and test the ink formulations. Environmental sustainability and regulatory compliance will be investigated and verified by SINTEF Ocean AS.

The GraphInk project has been launched by LayerOne AS with the primary objective of developing sustainable, cost-effective and scalable reduced graphene oxide (rGO)-based inks with electrical, mechanical and stability properties significantly superior to those of benchmark carbon-based inks and which are more cost effective and less toxic than conventional metal-based inks. The background is LayerOne's recent breakthrough in rGO conductivity with a new grade being two orders of magnitude more conductive than the standard grade. SINTEF is engaged as R&D supplier for the development of a commercially viable conductive ink based on this highly conductive material. Secondary objectives of the project are to improve the production method of rGO further with extensive characterization of the new rGO-grade and to develop a cost-efficient production method to bring down the unit production cost by a factor of 5. Furthermore, we will optimize the rGO-based ink formulations to achieve appropriate flow behaviour and printability, as well as investigate the surface tension and wettability with selected substrates. GraphInk will develop and produce at least one rGO-based ink with a resistivity < 1 ?/sq/25µm, which will have a shelf life =6 months. The ink should also be suitable for curing at low temperatures compatible with sensitive substrates (<150°C). Finally, environmental sustainability & regulatory compliance will be investigated and verified by SINTEF Ocean researchers relative to conventional metal-based inks. The ambition is to have the ink ready for commercialization by end of project.