Printing of temperature and humidity sensors on flexible substrates for biomedical applications

Printed electronics has become of great interest over the last few years, mainly because of the benefits it would bring. These advantages, a reduction of fabrication cost, an easy possibility to print on flexible substrates and the versatility can be easily applied to wearable and medical domains. Here we present results of a flexible hybrid-printed temperature and humidity sensor with printed electrodes using thermal transfer technic with a donor ribbon. Those electrodes are interdigitated and covered with graphene oxide. The innovative thermal transfer printing technology allows the deposition of various types of conductors in a solid state. It then contributes to have a resistivity nearer to the bulk as compared to other printing technics. A drop casting layer of graphene oxide acts as the temperature and humidity sensing material. His electrical properties change as function of the conditions. These kinds of printed sensors could be easily integrated into smart bandages.