Inks based on cellulosic materials for flexible, conformable and stretchable printed electronics

Electronic devices continue to evolve. Flexible, stretchable, and deformable electronic devices constitute a growing topic of interest for a wide variety of application fields such as in safety, medical, sport or automotive fields. Encres Dubuit is now active in this field by working on the development of innovative bio-based inks specifically designed for printing flexible, conformable and stretchable electronic devices.
These inks, suitable for screen-printing, are based on silver and cellulosic materials. This biobased matrix is interesting thanks to its non-toxicity, its natural abondance and its specific outstanding properties. Regarding ink development, the bio-based matrix helps to disperse and
stabilize active particles. It is also used as a rheological agent to meet the printing processes requirements and acts as an adhesion promoter concerning the interaction with the substrate.
These innovative materials are used to develop stable conductive inks with different scope of application. Flexible transparent conductive inks with high opto-electrical properties without. any sintering have been first developed. Then, to go beyond flexibility, an ongoing project specifically focuses on stretchability by designing a stretchable cellulose-based binder for the ink. This innovative approach tends to develop the next expected generation of inks. The challenge is to maintain the percolation between the active particles within the ink film while minimizing the electrical properties variations under strains applied to printed device.
This stretchable technology of ink could be transposed to other systems including colored pigments or active materials (conductive, sensitive, etc) to confer stretchable features for a wide range of applications.